Basic Electrical Diagnosis - DealerConnection · Basic Electrical Diagnosis March, 2006 Units of...

Ford Customer Service DivisionTechnical Training

Basic Electrical

Diagnosis

Student Guide

ORDER NUMBER: FCS-12970-REF

COURSE CODE: 34S14T0

January, 2008

34-Electrical Systems

3 5

R

1

42

PRND21

IMPORTANT SAFETY NOTICE

Appropriate service methods and proper repair procedures are essential for the safe, reliable operation of all motor vehicles,as well as the personal safety of the individual doing the work. This manual provides general directions for accomplishingservice and repair work with tested, effective techniques. Following them will help assure reliability.

There are numerous variations in procedures, techniques, tools and parts for servicing vehicles, as well as in the skill of theindividual doing the work. This manual cannot possibly anticipate all such variations and provide advice or cautions as to each.Accordingly, anyone who departs from instructions provided in this manual must first establish that he compromises neitherhis personal safety nor the vehicle integrity by his choice of methods, tools or parts.

As you read through the procedures, you will come across NOTES, CAUTIONS, and WARNINGS. Each one is there for aspecific purpose. NOTES give you added information that will help you to complete a particular procedure. CAUTIONS aregiven to prevent you from making an error that could damage the vehicle. WARNINGS remind you to be especially carefulin those areas where carelessness can cause personal injury. The following list contains some general WARNINGS that youshould follow when you work on a vehicle.

Always wear safety glasses for eye protection.

Use safety stands whenever a procedure requires youto be under the vehicle.

Be sure that the ignition switch is always in the OFFposition, unless otherwise required by the procedure.

Set the parking brake when working on the vehicle. If youhave an automatic transmission, set it in PARK unlessinstructed otherwise for a specific service operation. Ifyou have a manual transmission it should be in REVERSE(engine OFF) or NEUTRAL (engine ON) unless instructedotherwise for a specific service operation.

Operate the engine only in a well-ventilated area to avoidthe danger of carbon monoxide.

Keep yourself and your clothing away from moving partswhen the engine is running, especially the fan and belts.

To help prevent serious burns, avoid contact with hotmetal parts such as the radiator, exhaust manifold, tailpipe, catalytic converter and muffler.

Do not smoke while working on the vehicle.

To help avoid injury, always remove rings, watches,loose hanging jewelry, and loose clothing before begin-ning to work on a vehicle. Tie long hair securely behindyour head.

Keep hands and other objects clear of the radiator fanblades. Electric cooling fans can start to operate at anytime by an increase in underhood temperatures, eventhough the ignition is in the OFF position. Therefore,care should be taken to ensure that the electric coolingfan is completely disconnected when working under thehood.

The recommendations and suggestions contained in this manual are made to assist the dealer in improving his dealership partsand/or service department operations. These recommendations and suggestions do not supersede or override the provisions ofthe Warranty and Policy Manual, and in any cases where there may be a conflict, the provisions of the Warranty and Policy Manualshall govern.

The descriptions, testing procedures, and specifications in this handbook were in effect at the time the handbook was approvedfor printing. Ford Motor Company reserves the right to discontinue models at any time, or change specifications, design, or testingprocedures without notice and without incurring obligation. Any reference to brand names in this manual is intended merely asan example of the types of tools, lubricants, materials, etc. recommended for use. Equivalents, if available, may be used. Theright is reserved to make changes at any time without notice.

DANGER: Do not breathe dust or use compressed air to blow dust from storage containers or friction components. Removedust using government approved techniques. Friction component dust may be a cancer and lung disease hazard. Exposure topotentially hazardous components may occur if dusts are created during repair of friction components, such as brake pads andclutch discs. Exposure may also cause irritation to skin, eyes and respiratory tract, and may cause allergic reactions and/or maylead to other chronic health effects. If irritation persists, seek medical attention or advice. Failure to follow these instructions mayresult in serious personal injury.

Copyright © 2008 Ford Motor Company Produced and Coodinated byTechnical Support OperationsFord Customer Service Division

January 2008

CUSTOMER EXPECTATIONSM

Customer Expectations: Service1. Make it convenient to have my vehicle

serviced at your dealership.

2. The Service Advisor should demonstratea genuine concern for my service needs.

3. Fix it right the first time, on time.

4. Complete servicing my vehicle in atimely and professional manner.

5. Provide me with a clear and thoroughexplanation of the service performed.

6. Call me within a reasonable amount oftime after my service visit to ensure thatI'm completely satisfied.

7. Be responsive to questions or concernsthat I bring to your attention.

Expectation #3

“Fix It Right the First Time, on Time.”Both service advisors and technicians are important players when it comes to Expectation #3.

WhyCustomers tell us “Fixing It Right the First Time, on Time” is one of the reasons they woulddecide to return to a dealer to buy a vehicle and get their vehicles serviced.

Technician TrainingIt is our goal to help the technician acquire all of the skills and knowledge necessary to“Fix it Right the First Time, on Time.” We refer to this as “competency.”

Technician’s RoleAcquire the skills and knowledge for competency in your specialty via:

STST New Model— Web-Based — Web-Based— Instructor Led — Instructor Led

The BenefitsThe successful implementation of expectations means:

— Satisfied customers— Repeat vehicle sales— Repeat service sales— Recognition that Ford and Lincoln/Mercury technicians are “the Best in the Business”

TABLE OF CONTENTS

Basic Electrical Diagnosis January, 2008 Table of Contents -i

CONTENTS

COURSE INTRODUCTION................................................................COURSE INTRODUCTION–1

General Course Information ................................................................................................ Introduction–2Course Requirements .......................................................................................................... Introduction–2Course Objectives .............................................................................................................. Introduction–2Agenda ............................................................................................................................... Introduction–2

LESSON ONE ....................................................................................................................................... 1–1

Prerequisite Review ............................................................................................................................ 1–1Activity 1 ............................................................................................................................................. 1–7Activity 2 ........................................................................................................................................... 1–13Activity 3 ........................................................................................................................................... 1–15Activity 4 ........................................................................................................................................... 1–23Progress Review ................................................................................................................................ 1–29Activity 5 ........................................................................................................................................... 1–33Activity 6 ........................................................................................................................................... 1–37Activity 7 ........................................................................................................................................... 1–39Progress Review ................................................................................................................................ 1–45Activity 8 ........................................................................................................................................... 1–49Activity 9 ........................................................................................................................................... 1–51Homework ......................................................................................................................................... 1–55

LESSON TWO ...................................................................................................................................... 2–1

Workstation 1 ...................................................................................................................................... 2–1Workstation 2 .................................................................................................................................... 2–11Workstation 3 .................................................................................................................................... 2–25Workstation 4 .................................................................................................................................... 2–39Homework ......................................................................................................................................... 2–45

LESSON THREE ................................................................................................................................. 3–1

Instructor-Led Demonstration .............................................................................................................. 3–1Workstation 1 ...................................................................................................................................... 3–5Workstation 2 .................................................................................................................................... 3–11Workstation 3 .................................................................................................................................... 3–19Workstation 4 .................................................................................................................................... 3–31 Homework ........................................................................................................................................ 3–43

LESSON FOUR .................................................................................................................................... 4–1

Instructor-Led Demonstration .............................................................................................................. 4–1Workstation 1 ...................................................................................................................................... 4–3Workstation 2 ...................................................................................................................................... 4–7Workstation 3 .................................................................................................................................... 4–11

TABLE OF CONTENTS

Table of Contents -ii January, 2008 Basic Electrical Diagnosis

Workstation 4 ..................................................................................................................................... 4–21

LESSON FIVE....................................................................................................................................... 5–1

Workstation 1 ...................................................................................................................................... 5–1Workstation 2 ...................................................................................................................................... 5–5Workstation 3 ...................................................................................................................................... 5–9Workstation 4 .................................................................................................................................... 5–13

COURSE INTRODUCTION

Basic Electrical Diagnosis March, 2006 Introduction - 1

COURSEINTRODUCTION

COURSE INTRODUCTION

Introduction - 2 March, 2006 Basic Electrical Diagnosis

GENERAL COURSE INFORMATION

Course Description

This is the first instructor-led course in the Electrical/Electronics Curriculum. This course is designed to

provide hands-on opportunities for technicians to learn and improve their skills using tools and equipment,

and to apply knowledge learned in previous curriculum courses in actual diagnostic situations. Each day,

students will have at least four opportunities to practice selected tasks. Before the end of the course, they

will have had at least 16 opportunities to practice diagnostic and service skills. The results of the students’

work are recorded on worksheets.

Course Requirements

Each technician attending this course will be required to pass a combination of hands-on and written evaluations.

The evaluations will be administered on the afternoon of the fifth day.

Written Test

The student must answer at least 80% (24 out of 30) of the questions correctly to pass the written post-test.

Hands-On Evaluation

In order to pass the course, the student must demonstrate mastery of the skills covered at the evaluated hands-on

exercise.

The hands-on evaluation is a pass/fail type. It will be conducted with exercises in diagnosing electricalsystems.

Course Objectives

Upon successful completion of this course, the students will be able to:

Use the SSCC (Symptom-to-System-to-Component-to-Cause) diagnostic process relating to electricalconcerns.

Use special tools and service equipment associated with electrical diagnosis and repair.

Use all service publications in their available formats to obtain needed information for diagnosis.

Perform diagnostic test procedures.

Agenda

DAY ONE: Introductions, Prerequisite Review, Lesson 1 Workstations

DAY TWO: Lesson 1 Workstation Reviews, Lesson 2 Workstations

DAY THREE: Lesson 2 Workstation Reviews, Lesson 3 Workstations

DAY FOUR: Lesson 3 Workstation Reviews, Lesson 4 Workstations

DAY FIVE: Lesson 4 Workstation Reviews, Lesson 5 Workstations , Final Review, Post-Test

LESSON ONE - PRERQUISITE REVIEW

Basic Electrical Diagnosis March, 2006

PREREQUISITE REVIEW

1 - 1

LESSON ONE - PREREQUISITE REVIEW

March, 2006 Basic Electrical Diagnosis

BED106-A/VF

12V

E

F

A

BC D

2. Give three examples of good conductive materials and three examples of good insulating materials:

1. Identify the 6 elements of a circuit:

A.

B.

C.

D.

E.

F.

PREREQUISITE REVIEW

srotcudnoC srotalusnI

1 - 2



3. Describe/Define Voltage:

4. Which digital multi-meter (DMM) setting is used to measure voltage?

5. In the illustration that follows, draw a complete circuit using the elements in question one. Drawmeter leads to represent measuring available voltage to the bulb.

BED107-A/VF

1 - 3



BED108-A/VF

6. Describe/Define Current:

8. In the illustration that follows, draw a complete circuit using the elements from question one. Drawmeter leads to represent measuring current flow in the circuit.

1 - 4

7. Which digital multi-meter (DMM) setting is used to measure current?



BED109-A/VF

9. Describe/Define resistance:

10. Which digital multi-meter (DMM) setting is used to measure resistance?

11. In the illustration that follows, draw a complete circuit using the elements from question one. Drawmeter leads to represent measuring resistance of the bulb.

1 - 5



BED104-A/VF

L4

L3

L2

L1

12V

L4

L3

L2

L1

SERIES CIRCUIT PARALLEL CIRCUIT

12V

12. Draw series and parallel circuits in the diagrams below:

13. The sentences below describe parts of Kirchoff’s laws. Complete the sentences.

b. The highest in a series circuit uses the most voltage.

a. In a series circuit, all of the is used by the load(s) in the circuit.

1 - 6

LESSON ONE - ACTIVITY 1


ACTIVITY 1

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DIRECTIONS: In this activity you will learn about resistance using a digital multi-meter (DMM) and aresistor board.

1. What is resistance?

2. What unit of measure is used to measure resistance?

3. What must be done to the circuit to prepare for testing resistance?

4. What digital multi-meter setting is used to measure resistance?

5. Where should the black meter lead be connected to the meter?

6. Where should the red meter lead be connected to the meter?

ACTIVITY 1 RESISTANCE MEASUREMENT

1 - 8



Units of Measure

To diagnose and repair electrical problems, you must be able to accurately read and convert commonunits of measurement. Automotive electrical work uses metric system prefixes for common measures.The most common prefixes are:

M= Mega: a number times one million (for example, 1MΩ = 1 million ohms)

k = Kilo: a number times one thousand (for example, 1kΩ = 1 thousand ohms)

m = Milli: a number divided by one thousand (for example, 1mA = .001 amps)

Each of these metric prefixes multiplies or divides a whole number by either one thousand or onemillion. Fortunately, you do not actually have to do multiplication or division when you convert fromone unit to another. You simply have to move the decimal point the proper number of places in thecorrect direction.

To help visualize this, think of the metric system in terms of a number line, as shown. To convert fromone unit to the next, simply count the number of places you must travel along the number line.

BED170-A/VF

Volts (V)Amps (A)Ohms ( )

Kilo(k)

Mega(M)

Milli(m)

1 - 9



To begin using the number line, first look at the units of the number you are working with to find yourstarting point. For example, if you had 50 mA, your starting point would be at Milli (m) on the numberline. Then you would count the number of places between your starting point and the unit you want toconvert to. For example, to convert 50 mA to amps, you would count three places to the left to reachAmps (A). This means that you would move your decimal point three places to the left. So 50 mA =.050 A.

What if you had 70kΩ? How many ohms would you have? From your starting point, which would beKilo (k), you would move across the number line three places to the right to Ohms (Ω). The decimalwould also move three places to the right. So 70kΩ = 70,000 Ω.

BED171-A/VF


Kilo(k)

.050 A 50. mA

Mega(M)

Milli(m)

0 5 0. mA

.050 A

BED172-A/VF


Kilo(k)

70. k 70,000.

Mega(M)

Milli(m)

70,000

70.0 0 0 k

1 - 10



7. Set up the digital multi-meter (DMM) to measure resistance. Measure the resistance of each resistoron the board and complete the table below:

tnemerusaeMrotsiseR elohWaotdetrevnoCrebmuN

nahTretaerGtnemerusaeMehtsI?smhO000,01

)onroseyelcric(

.1 ONSEY

.2 ONSEY

.3 ONSEY

.4 ONSEY

.5 ONSEY

6. ONSEY

.7 ONSEY

.8 ONSEY

.9 ONSEY

.01 ONSEY

.11 ONSEY

.21 ONSEY

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NOTES

1 - 12


Basic Electrical Diagnosis March 2006

ACTIVITY 2

1 - 13


March 2006 Basic Electrical Diagnosis

DIRECTIONS: In this activity you will use a digital multi-meter (DMM) to learn about resistance in aseries circuit. Use the digital multi-meter (DMM), lamp board and jumper wires to answer thefollowing questions by filling in the blanks.

1. Measure the resistance of lamps L1, L2, and L3, add the resistances together and enter your readingsbelow:

L1

L2

L3

Total

2. Measure the resistance of one jumper wire and record your reading:

Entire Circuit

3. Build a series circuit with lamps L1, L2, and L3 using the lamp board provided. Measure the resis-tance of the entire circuit and enter your reading below:

Wire

4. The total calculated value from question #1 is the measured value from question #3.

A. less than

B. approximately the same as (+ or – 0.5 ohms)

C. greater than

5. In a series circuit, total circuit resistance is the sum of the individual resistances.

A. less than

B. approximately the same as (+ or – 0.5 ohms)

C. greater than

Workstation is complete. Return it to its original condition.

ACTIVITY 2 SERIES CIRCUIT: RESISTANCE

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ACTIVITY 3

1 - 15



DIRECTIONS: In this activity you will use a digital multi-meter (DMM) to learn about voltage drop ina series circuit.

1. What is voltage?

2. What unit of measure is used to measure voltage?

3. What must be done to the circuit to prepare for testing voltage?

4. What digital multi-meter (DMM) setting should be used to measure voltage?



ACTIVITY 3 SERIES CIRCUIT: VOLTAGE DROP

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L2

L3

L4

L1

12V

BED105-A/VF

Set up the power supply as follows:

• Turn on the power supply

• Adjust the Amps setting to maximum

• Setup the digital multi-meter (DMM) to measure DC volts

• Connect the digital multi-meter (DMM) leads to the positive and negative terminals at the rear of thepower supply.

• Adjust the volts knob on the power supply until the digital multi-meter (DMM) reads approximately12 volts.

7. Connect positive and negative jumper wires from the power supply to lamp L1. Measure the voltagedrop across the load as shown and record your reading:

L1

1 - 17



8. Measure the voltage drop across one of the jumper wires as shown and record your reading:

Wire

L2

L3

L4

L1

12V

BED110-A/VF

1 - 18



9. Connect lamp L2 in series with L1 as shown and measure the voltage drop across L1, then L2, andthen add the values:

Total

10. Is your total in question #9 within 0.2 volts of the source voltage?

(circle one) Yes No

L1

L2

L2

L3

L4

L1

12V

BED111-A/VF

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11. Connect L3 in series with L1 and L2 as shown and measure the voltage drop for each of the lamps,L1, L2, L3, then add the values:

12. Is your total in question #11 within 0.2 volts of the source voltage?

(circle one) Yes No

Total

L1

L2

L3

L2

L3

L4

L1

12V

BED112-A/VF

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13. Use Kirchhoff’s Law to explain the previous results:

Do not disconnect the lamp board. Let the Instructor know you have completed the activity.

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NOTES

1 - 22



ACTIVITY 4

1 - 23



DIRECTIONS: In this activity you will use a digital multi-meter (DMM) to learn about current in aseries circuit.

1. What is current?

2. What unit of measure is used to measure current?

3. What digital multi-meter (DMM) setting should be used to measure current?



6. How should the meter leads be placed in the circuit to measure current?

ACTIVITY 4 SERIES CIRCUIT: CURRENT

1 - 24


Basic Electrical Diagnosis September, 2006

7. Set up the digital multi-meter (DMM) to measure current through L1 as shown and record yourreading.

NOTE: Before turning on the power supply ask the instructor to review your connections

L1

L2

L3

L4

L1

12V

BED113-A/VF

1 - 25



8. Add lamps L2 and L3 to the circuit in series as shown and measure current through all lamps.

L1

L2

L3

L4

L1

12V

BED114-A/VF

9. The current measurement from question #8 is _________________the current measurement fromquestion #7.

a. less thanb. approximately the same asc. greater than

1 - 26



10. Connect the circuit and the digital multi-meter (DMM) as shown and measure the current.

Total

L2

L3

L4

L1

12V

BED147-A/VF

11. The current measurement from question #10 is _________________the current measurement fromquestion #8.

A. less than

B. approximately the same as

C. greater than

12. Current flow measured anywhere in a series circuit is _______________________________throughout the circuit.


1 - 27



NOTES

1 - 28

LESSON ONE - PROGRESS REVIEW


PROGRESS REVIEW

1 - 29



DIRECTIONS: Answer questions 1 through 4 with your instructor. After completing these questionstogether, complete the remaining questions on your own.

1. The sum of the individual voltage drops in a series circuit is equal to:

2. In a series circuit, the resistance drops the most voltage.

3. Total resistance in a series circuit is equal to the sum of:

4. Amperage, when measured in a series circuit, is:

7. What happens to resistance when more loads are added to a series circuit?

8. How should you connect the digital multi-meter to the circuit to measure current flow in a seriescircuit?

DIRECTIONS: Complete the following questions on your own.

5. In a series circuit, total circuit resistance is equal to:

6. The total of all voltage drops in a series circuit are equal to:

PROGRESS REVIEW ACTIVITIES 1 - 4

1 - 30



9. Current flow in a series circuit is the same no matter where you measure it.

A. True

B. False

10. According to Kirchoff’s law, the sum of the individual voltage drops in a series circuit equals thevoltage of the:

12. According to Ohm’s Law, as resistance increases, what happens to current flow?

13. How does heat affect resistance?

11. According to Kirchoff’s law, with loads of different resistances, which load will drop the mostvoltage?

14. How are Watts determined?

1 - 31



NOTES

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ACTIVITY 5

1 - 33


September, 2006 Basic Electrical Diagnosis

L2

L3

L4

L1

12V

BED115-A/VF

1. Measure the resistance of lamp L1 and enter your reading below.

L1

DIRECTIONS: In this activity you will use a digital multi-meter (DMM) to learn about resistance in aparallel circuit. Use the digital multi-meter (DMM), lamp board and jumper wires to answer thefollowing questions by filling in the blanks.

2. Build a parallel circuit using lamps L1, L2 and L3 as shown, then measure total circuit resistance.

Total

ACTIVITY 5 PARALLEL CIRCUIT: RESISTANCE

1 - 34



3. The total circuit resistance measurement from question #2 is _________________the individualresistance measurement from question #1.

A. less than


C. greater than

4. In a parallel circuit, total circuit resistance is _______________________________ the smallestindividual resistance in the circuit.

A. less than


C. greater than


1 - 35


January, 2008 Basic Electrical Diagnosis

NOTES

1 - 36



ACTIVITY 6

1 - 37



1. Connect positive and negative jumper wires from the power supply to L1. Measure the voltage dropacross the load and record your reading.

L1

DIRECTIONS: In this activity you will use a digital multi-meter (DMM) to learn about voltage drop ina parallel circuit. Set up the power supply as follows:

• Turn on the power supply.

• Adjust the Amps setting to maximum.

• Setup the digital multi-meter (DMM) to measure DC volts.

• Connect the digital multi-meter (DMM) leads to the positive and negative terminals at the rear of thepower supply.

• Adjust the volts knob on the power supply until the digital multi-meter (DMM) reads approximately12 volts.

2. Add bulbs L2 and L3 in parallel and measure the voltage drop of each bulb:

L1

L2

L3

3. Compare the results of the voltage drop test from the series circuit in Activity 3 to the results fromthe parallel circuit. Is there a difference?

4. If there is a difference, explain why:


ACTIVITY 6 PARALLEL CIRCUIT: VOLTAGE DROP

1 - 38



ACTIVITY 7

1 - 39



1. Set up the digital multi-meter (DMM) to measure current through L1 as shown and record yourreading.

NOTE: Before turning on the power supply ask the instructor to review your connections

L1

DIRECTIONS: In this activity you will use a digital multi-meter (DMM) to learn about current in aparallel circuit. Using the lamp board, a regulated power supply, a digital multi-meter (DMM) andjumper wires, answer the following questions by filling in the blanks:

2. Leave the meter connected and add lamp L2 in parallel. Measure current flow through both lampsand record your reading:

L1 and L2

3. Add lamp L3 in parallel and measure current flow through all lamps and record your reading:

L1, L2 and L3

ACTIVITY 7 PARALLEL CIRCUIT: CURRENT

1 - 40

L2

L3

L4

L1

12V

BED113-A/VF



BED116-A/VF

L4

4. Move the meter leads as shown to measure the current flow through just lamp L3 and record yourreading:

L3

1 - 41



BED117-A/VF

L4

5. Measure the current flow through lamp L2 only as shown, then repeat for lamp L1 and record yourreading:

L2

L1

6. Add together the readings obtained in questions #4 and #5.

L1

L2

L3

Total

1 - 42



7. Total current flow in a parallel circuit is _________________the sum of the current flow in theindividual branches.

A. less than

B. equal to

C. greater than


1 - 43



NOTES

1 - 44



PROGRESS REVIEW

1 - 45



Parallel Circuits

DIRECTIONS: Answer questions 1 through 5 with your instructor. After completing those questionstogether, complete the remaining questions on your own.

1. The individual voltage drops of each load in a parallel circuit are equal to:

2. As more loads are added to a parallel circuit, total circuit resistance:

3. In a parallel circuit, the total circuit resistance will always be:

4. Total current flow in a parallel circuit is equal to:

5. As more loads are added to a parallel circuit, current flow:

PROGRESS REVIEW ACTIVITIES 5 - 7

1 - 46



DIRECTIONS: Complete the following questions on your own.

6. In a parallel circuit, how much voltage is dropped at each of the loads?

7. Total circuit resistance ______________in a parallel circuit when more loads are added.

A. decreases

B. increases

C. stays the same

8. In a parallel circuit, the total circuit resistance will always be ___________the smallest resistance inthe circuit.

A. equal to

B. less than

C. greater than

9. As more loads are added to a parallel circuit, what happens to current flow?

10. Total current flow in a parallel circuit is ________________ the sum of current flow in the indi-vidual circuits.

A. less than

B. greater than

C. equal to

1 - 47



NOTES

1 - 48



ACTIVITY 8

1 - 49



DIRECTIONS: In this activity you will learn about series-parallel circuits. Using jumper wires,construct a series-parallel circuit on the lamp board as shown. Once you have wired the circuit, turn onthe power supply.

L1

1. Why do you think the lamps light the way they do?

NOTE: Wait for the instructor to complete the activity.

x =

L2 x =

L3 x =

ACTIVITY 8 SERIES - PARALLEL CIRCUITS

1 - 50

V A W

V A W

V A W


Basic Electrical Diagnosis January, 2008

ACTIVITY 9

1 - 51



ACTIVITY 9OPEN CIRCUITS

DIRECTIONS: In this activity you will use a digital multi-meter (DMM) to learn about voltagemeasurements in an open circuit.

Set up the power supply as follows:

• Turn on the power supply

• Adjust the Amps setting to maximum

• Setup the digital multi-meter (DMM) to measure DC volts

• Connect the digital multi-meter (DMM) leads to the positive and negative terminals at the rearof the power supply.

• Adjust the volts knob on the power supply until the digital multi-meter (DMM) reads approxi-mately 12 volts.

1. Connect L1, L2 and L3 in series with the wire between L2 and L3 disconnected (open circuit).Measure the voltage drop of one of the jumper wires as shown and record your reading:

Wire _________________ V

2. Measure the voltage drop for each of the lamps and record the readings:

L1 _________________ V

L2 _________________ V

L3 _________________ V

1 - 52



3. Use Ohm’s Law to explain the previous results:

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

4. Connect the meter across the open as shown and record the reading.

Voltage across the open _____________________ V

5. Explain the previous result:

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

1 - 53



NOTES

1 - 54

LESSON ONE - HOMEWORK


HOMEWORK

1 - 55



DIRECTIONS: This homework assignment has two parts:

• Answering review questions about the activities you completed on Day One.

• Reading about wiring harness service and repair and answering questions.

Answer the following review questions by filling in the blanks.

Voltage

1. What is voltage?

2. What unit of measure is used to measure voltage?

3. What must be done to the circuit to prepare for testing voltage?

4. What digital multi-meter (DMM) setting should be used to measure voltage?



HOMEWORK

1 - 56



7. What is current?

8. What unit of measure is used to measure current?

9. What digital multi-meter (DMM) setting should be used to measure current?



12. How should the meter leads be placed in the circuit to measure current?

Current

1 - 57



13. What is resistance?

14. What unit of measure is used to measure resistance?

15. What must be done to the circuit to prepare for testing resistance?

16. What digital multi-meter setting is used to measure resistance?



Resistance

1 - 58



19. The sum of the individual voltage drops in a series circuit is equal to:

20. In a series circuit, the resistance drops the most voltage.

22. Amperage, when measured in a series circuit, is:

21. Total resistance in a series circuit is equal to the sum of:

Series Circuits

Parallel Circuits

24. As more loads are added to a circuit in parallel, total circuit resistance:

23. The individual voltage drops of each load in a parallel circuit are equal to:

25. In a parallel circuit, the total circuit resistance will always be the smallestindividual resistance in the circuit.

27. As more loads are added to a parallel circuit, current flow:

26. Total current flow in a parallel circuit is equal to:

Circuit Arrangements

28. What are the three ways that circuits can be arranged?

1 - 59

Open Circuit Voltage Testing

29. How much voltage will drop across the loads of a circuit that has a disconnected wire (open circuit)?



BED014-A/VF

1 2

Read the following information on wiring harness service and repair, then answer the questions aboutthe reading.

Hard Shell Connector Service

Many different styles of electrical connectors are used on Ford Motor Company vehicles. Connectorshells should be replaced anytime they show evidence of being damaged from burning, melting, breaksor cracks. Likewise, individual terminals should be replaced if they become damaged from burning,corrosion or breaks.

Separating Connectors

For connectors with a lift type locking tab:

! CAUTION: Raise locking tab just enough to release connector halves. If locking tab breaks, that

connector half must be replaced for reliable repair.

1. Insert a flat-blade screwdriver under locking tab and gently twist.

2. Grasp wires and pull to separate.

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1 - 60



For connectors with a push type locking tab:

1. Push on the locking tab with your thumb or screwdriver.


For connectors with a slide locking tab

1. Slide or pull the locking mechanism to unlock the connector.

2. Push on the locking tab with your thumb.


BED168-A/VF

BED165-A/VF

1 - 61



For bolted connectors:

1. Separate the connector by loosening the bolt in the center of the connector. The bolt will separate theconnector as it is loosened.

! CAUTION: Do not use power tools with bolted connectors. Damage to the connector may result.

BED166-A/VF

1 - 62



Disassembling Connectors

Ford Blade Connectors are identified by the T shaped (or joined T shaped, I shaped) cavities in themating end of the socket half of the shell. The blades and sockets are held in the shell by plastic lockingfingers which are part of the shell, and which snap into rectangular cutouts in the blades and sockets.

The sockets are designed to make firm contact against both sides of the blades.

To remove a terminal from a Ford blade connector:

1. Lift the latch tongue and pull the connector halves apart. The spring-loaded features of the socketsagainst the blades make the connectors characteristically difficult to pull apart.

2. Use a small screwdriver or pick to lift the locking finger away from the terminal. The finger must beforced well back to free the terminal.

3. Pull on the wire to withdraw the terminal.

To install a terminal into a Ford Blade connector:

1. Insert the terminal into the shell.

2. Push on the wire until the terminal snaps in place.

1 - 63



Locking wedge connectors can be identified by wedges that are sometimes visible through windows inthe connector shell. The terminals are held in the shell by plastic retaining fingers, which are part of theshell.

To remove a terminal from a locking wedge connector:

1. Separate the connector halves. Some connectors have locking tabs that need to be lifted and somethat need to be pushed.

2. Remove the wedge.

3. Use a small screwdriver or a pick to lift the retaining finger away from the terminal.

4. Pull on the wire to withdraw the terminal.

To install a terminal in a locking wedge connector:

1. With the wedge removed, insert the terminal into the shell, until the retaining finger engages theterminal.

2. Install the wedge.

BED002-A/VF

1 - 64



Tang Type Connectors are primarily used to connect the harness to various components like an ignitionswitch. Terminals are held in place by tangs on the terminals that snap behind lips in the shell.

To remove a terminal from a tang type connector:

1. Disconnect the connector from the component.

2. Insert a small screwdriver or pick into the narrow slot beside the terminal.

3. Push on the wire and press in on the screwdriver or pick to force the tang down flush with the termi-nal.

4. Pull on the wire to withdraw the terminal from the shell.

To install a terminal into a Tang Type connector:

1. Align the tang on the socket with the narrow slot on the shell.

2. Push in on the socket until the tang snaps into place behind the lip in the shell.

BED004-A/VF

1 - 65



BED160-C

1

2

On occasion, it may become necessary to repair a wire in a harness that is chaffed or broken. This can beaccomplished by splicing the wire with a solder/heat shrink or crimp/heat shrink repair procedure. Theseprocedures can also be used when correcting a damaged connector or terminal. When replacingdamaged connectors or terminals, you can replace either the individual terminal or the entire connectorwith all of its terminals. The proper replacement terminals and connectors can be found on the PTS web-site.

When a repair is necessary care should be taken to perform the procedure properly. When stripping thewires insure that there are no frayed wires prior to carrying out the solder or crimp.

Wiring Repair

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1 - 66



BED164-A/VF

1

2

The durability of a splice is dependent on keeping the moisture out of the joint. Heat shrink tubing alonewon’t do it. The tubing must contain a “hot melt wax” which forms an adhesive seal between the wireinsulation and the tube. A flameless heat source such as Rotunda 164-R5902 should be used to heat thetubing. Care should be taken not to burn the tubing, as burnt tubing may leak and cause future corrosion.

Either the solder/heat shrink procedure or the crimp/heat shrink procedure can be used to perform asplice repair. However, the crimp/heat shrink should be the method used on larger gauge wires, as it isdifficult to sufficiently heat the splice to perform a proper solder repair. On smaller gauge wires thesolder/heat shrink procedure is preferred because a solder splice is a better electrical repair than a crimpsplice.

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1 - 67



1. Disconnect the battery ground cable.

2. Strip the wires to the appropriate length.

Solder/Heat Shrink Repair Wire Repair

19mm(0.75")

38mm(1.5")

1

2

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1 - 68



BED161-A/VF

2

3

1

13mm(0.5")

3. Install the heat shrink tubing.

4. Twist the wires together.

5. Solder the wires together.

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NOTE: Use rosin core mildly-activated (RMA) solder. Do not use acid core solder.

1 - 69



BED162-A/VF

3

2

1

6. Bend wire 1 back in a straight line.

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NOTE: Wait for solder to cool before moving the wires.

1 - 70



BED164-A/VF

1

2

BED163-A/VF

1

3

13mm(0.5")

13mm(0.5")

25mm(1")

51mm(2")

2

7. Evenly position the heat shrink tubing over the wire repair.

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8. Use a shielded heat gun to heat the repaired area until the adhesive flows out of both ends of the heatshrink tubing.

9. Reconnect the battery ground cable.

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NOTE: Overlap the tubing on both wires.

1 - 71



Crimp/Heat Shrink Repair Wire Repair

1. Disconnect battery ground cable.

2. Strip ¼” (6.35mm) of insulation from each wire end, taking care not to nick or cut wire strands.

3. Install heat shrink tubing.

1 - 72

ADHESIVE LINING

HEAT

SHRINK TUBING



4. Select appropriate wire splice for the wires to be spliced.

5. Identify the appropriate crimping chamber on the Rotunda 164-R5901 Pro-Crimper by matching thewire size on the dies with the wire size stamped on the butt splice.

NOTE: Rotunda 164-R5901 Pro-Crimper is the only tool that can be used with these splices.

1 - 73

CAVITY

INDENTER

CRIMPINGCHAMBER

22-18

16-14

12-1022-18



6. Center one end of the wire splice in the appropriate crimping chamber.

7. Insert stripped wire into the barrel.

8. Holding the wire in place, squeeze tool handles until ratchet releases.

9. Repeating steps 5-7, crimp the other half of the splice.

1 - 74

BRAZED SEAM

INDENTER

WIRE STOPPER



10. Check for acceptable crimp.

a. Crimp should be centered on each end of the butt splice.

b. Wire insulation does not enter butt splice.

c. Wire is visible through inspection hole of splices.

11. Evenly position supplied heat shrink tubing over wire repair.

12. Use shielded heat gun to heat the repaired area until adhesive flows out of both ends of the heatshrink tubing.

13. Reconnect battery ground cable

1 - 75

A

B

C

ADHESIVE LINING

HEAT

SHRINK TUBING



Fuse Link Service

! WARNING: ALWAYS DISCONNECT BATTERY GROUND CABLE PRIOR TO SERVICING

ANY FUSE LINK. REFER TO THE APPROPRIATE WORKSHOP MANUAL, BATTERY

SECTION.

If a circuit protected by a fuse link becomes inoperative, inspect for a blown fuse link. If the fuse linkwire insulation is burned or opened, disconnect the feed as close as possible behind the splice in theharness. If the damaged fuse link is between two splices (weld points in the harness), cut out thedamaged portion as close as possible to the weld points.

! CAUTION: Do not fabricate a fuse link from ordinary wire because the insulation may not be flame

proof.

CAUTION: Do not mistake a resistor wire for a fuse link. The resistor wire is generally longer and

has print stating “Resistor—do not cut or splice.”

CAUTION: Before replacing a fuse link, be sure to find and correct the electrical condition that

caused the link to blow.

If it becomes necessary to replace a fuse link in a wiring assembly, make sure the replacement fuse linkis a duplicate of one removed with respect to gauge, length and insulation. Original and Fordreplacement fuse links have insulation that is flameproof.

!

!

1 - 76



BED018-A/VF

1

2

NOTE: Some replacement fuse links are a small length of wire and others have an eyelet terminal foran 8 mm (5/16 inch) stud on one end. Always select the appropriate fuse link by the gauge size and theneed for an eyelet.

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M-625A41-ZA3D 02.oN teleyeo/w eulB

1 - 77



BED022-B/VF

1

2

To service a fuse link, cut off the open fuse link and the original splice(s). Use the crimp/heat shrinkprocedure to splice in the new fusible link (using solder may allow solder to flow through the fuse linkand allow the link to carry more current than it is designed for).

Non-Eyelet Type Fuse Link Replacement

BED021-A/VF

1

2

Eyelet Type Fuse Link Replacement

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1 - 78



BED020-B

44

5

7

6

1

3

2

To service a two-link eyelet group when only one link has blown and other link is not damaged, proceedas follows:

1. Cut out blown fusible link (two places).

2. Use the crimp/heat shrink procedure to splice a new eyelet type fuse link to the cut wire.

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Servicing a Multi-Link Eyelet Fuse Link Group

1 - 79



30. When should you replace a connector shell?

31. When should you replace the individual terminals in a connector?

32. What must be done if the locking tab of a connector is broken when separating the connector?

33. How do you remove the pins from a locking wedge connector?

34. What condition(s) can affect the durability of a wire splice?

35. What type of solder should be used when performing a solder/heat shrink repair?

36. After stripping a wire, what should be done prior to splicing the wires together?

1 - 80



37. When should you stop heating the wax-melt heat shrink tubing?

38. Why is a crimp/heat shrink splice the better choice for large gauge wire?

39. What type of splice should be used when replacing a fuse link?

1 - 81



NOTES

1 - 82

LESSON TWO - WORKSTATION 1


WORKSTATION 1

2 - 1



34

34

57

Fault A

Fault B

BED167-B

DIRECTIONS: Each technician in this course is designated as Technician A, B or C. The activities ineach workstation are divided among the three technicians so that each technician performs some of thehands-on activities at each workstation. While one technician performs the hands-on, the othertechnicians observe. This ensures that each technician has a chance to perform the hands-on activities.

Using the circuit fault board, a 12V battery pack, jumper wires and a DMM, complete the followingactivities and answer the questions by filling in the blanks. In this workstation you will learn aboutcommon circuit faults including opens, high resistance, and shorts to ground.

1. Connect a jumper wire from the negative lead of the battery pack to the negative terminal (G108) ofthe light board. Connect a second jumper wire to the positive lead of the battery pack and to thepositive terminal of the light board. Connect the DMM to the negative and positive terminals of thelight board and record the source voltage reading:

Source

WORKSTATION 1 CIRCUIT FAULT ANALYSIS

2 - 2



2. Check available voltage to each of the connectors and the lamp by turning on the switch, connectingthe negative lead of the DMM to G108 and the positive lead to C100, C200 and C300 of circuit 34.Record your readings at each point:

C100 C200 C300

Are all available voltage readings within 0.5 volts of source voltage? YES NO

3. Measure positive circuit (CKT 34) voltage drop by connecting the DMM positive lead to thepositive terminal (B+) on the light board and the negative lead to C100, C200, and C 300 of CKT34, and record the voltage reading at each point:

C100 C200 C300

4. Measure negative circuit (CKT 57) voltage drop by connecting the DMM negative lead to thenegative terminal (G108) on the light board and the positive lead to C100, C200, and C 300 of CKT57, and record the voltage reading at each point:

C100 C200 C300

5. Explain why the voltage drop values vary between connectors:

6. Are any of the voltage drop readings greater than .5 Volts? YES NO

7. What would a voltage drop reading greater than .5 volts indicate?

2 - 3



Technician B

8. Turn the switch OFF. Create an open by disconnecting Fault Point A (CKT 34). Turn the switch ON.What is the last connector where you would expect to have available voltage?

10. In a properly operating circuit, what reading would you expect from a voltage drop test betweenC300 Circuit 57 and the negative terminal?

15. In a properly operating circuit, what available voltage reading would you expect at the bulb?

9. Measure the available voltage at all connectors. Do your readings verify your answer to question #8?

YES NO

Turn the switch OFF. Reconnect fault point A (CKT 34) and disconnect fault point B (CKT 57). Turnthe switch ON.

11. Perform a voltage drop test between C300 Circuit 57 and the negative terminal and record yourreading:

12. Explain why you got the reading in Step 11.

13. In this faulty circuit, what is the last connector in circuit 57 where you would expect to have volt-age?

14. Measure the voltage at all connectors. Do your readings verify your answer to question #13?

YES NO

Turn switch OFF. Reconnect Fault point B. Turn switch ON momentarily to verify your repair. Turnswitch OFF. Remove the bulb and insert the other bulb provided at the workstation. Turn switch backON.

2 - 4



16. Check available voltage on circuit 34 at C300 and record your reading:

Does your reading indicate a concern with circuit 34? YES NO

If yes, explain:

21. What is the cause of the concern in this circuit?

A. High resistance

B. Open

C. Short to ground

D. Short to power


18. Perform a voltage drop test between C300 Circuit 57 and the negative terminal and record yourreading:

Does your reading indicate a concern with the ground circuit? YES NO

If yes, explain:

19. Based on your voltage readings obtained in questions 16 and 18, what component is at fault:

20. To verify your diagnosis perform a voltage drop test across the load, and record your results:

2 - 5



Technician C

22. Turn the switch OFF. Remove the bulb and reinstall the original bulb. Turn the switch ON. Verifythe circuit operates properly. Turn the switch OFF. Move the end of the red lead from the left sideof the resistor (fault A) to the right side of the resistor so that the resistor becomes part of the circuit.Turn the switch ON. What happened to the bulb?

23. In a properly operating circuit, what available voltage reading would you expect at the bulb?

24. Measure the available voltage at the bulb and record your reading:

25. In a properly operating circuit, what reading would you expect from a voltage drop test betweenC300 Circuit 34 and the positive terminal?

26. Perform a voltage drop test between C300 Circuit 34 and the positive terminal and record yourreading

Do your readings indicate a concern with circuit 34? YES NO

If yes, explain:

2 - 6



28. Perform a voltage drop test between C300 Circuit 57 and the negative terminal and record yourreading

Does your reading indicate a concern with circuit 57? YES NO

If yes, explain:


A. High resistance

B. Open

C. Short to ground

D. Short to power


29. In this faulty circuit, where is the last point you would expect to get a good available voltage read-ing:

30. Measure the voltage at all connectors. Do your readings verify your answer to question #29?

YES NO

2 - 7



All Technicians

32. Turn switch OFF. Move the end of the red lead from the right side of the resistor back to the leftside of the resistor. Insert another jumper wire, located at the workstation, between Fault A andFault B. Turn switch on. Explain what happens:

33. Check available voltage to bulb and record your reading:

35. Perform a voltage drop on the circuit breaker and record your reading:

34. In a properly operating circuit, what reading would you expect from a voltage drop test performedacross the circuit breaker

Does your reading indicate a concern with the circuit breaker? YES NO

If yes, explain:

36. Install the Short Circuit Test Lamp in place of the Circuit Breaker. Explain why the test lamp lights,but the circuit board lamp does not:

2 - 8



37. Disconnect C300 and observe the test lamp. Is the lamp still lit?

Explain why:

38. Reconnect C300. Disconnect C100 and observe the test lamp. Is the lamp still lit?

Explain why:

Explain why:

39. Reconnect C100. Remove the jumper wire between the power side (CKT 34) and the ground side(CKT 57) and observe the test lamp. Did the brightness of the lamp change?


A. High resistance

B. Open

C. Short to ground

D. Short to power

Workstation is complete. Return the workstation to its original condition.

2 - 9



NOTES



WORKSTATION 2

2 - 11




In this workstation you will learn how some automotive components operate and how to test them. Thecomponents you will test include switches and relays.

1. Technician A: Using the power window switch schematic and the component testing procedure thatfollows, perform the tests on the power window switch at the workstation. All technicians: Fill inthe blanks with your answers.

WORKSTATION 2 COMPONENT TESTING

2 - 12



2. Is the switch good? (circle one) YES NO

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2 - 13



3. Technician B: Using the blower motor switch schematic and the component testing procedure thatfollows, perform the tests on the blower motor switch provided. All technicians: Fill in the blankswith your answers.

BED179-A/VF

2 - 14



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Technician B

2 - 15



4. Technician C: Using the main light switch schematic and the component testing procedure thatfollows, perform the tests on the headlamp switch and fill in the blanks.

MAIN LIGHT SWITCH

INST. PANEL

DIMMERSWITCH

15 (RD/YE)

12 (LG/BK) 13 (WH/LG)

14 (BR) 19 (LB/RD) 53 (BK/LB)

38 (BK/OG) 195 (BK/OG) 54 (BK/OG)

57 (BK)

57 (BK)57 (BK)

57 (BK)

DOME

DIMMER

DOME

HEAD

B+

PANEL DIM

LOHI

FRONTPARK

FRONTPARK

LOWBEAM

HIGHBEAM

HIGHBEAMINDICATORLAMP

LOWBEAM

HIGHBEAM

BED158-A/VF

OFFPARK

HEAD OFFPARK

2 - 16



Technician C

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2 - 17

5. Is the switch good? (circle one) YES NO



6. A relay is an electromagnetic switch that uses a amount of current to control a

amount of current.

7. Technician A: Using the blower motor schematic and the component testing procedure that follows,perform the tests on the blower motor relay. Fill in the blanks with your answers.

BED156-A/VF

87A 87

8530

86 BLOWERRELAY

57 BK

10A

CENTRALJUNCTIONBOX

22

14

C243

HOT IN RUN

BLOWER/FLASHERRELAYBLOCK

BLOWER MOTORRESISTOR

1.38Ω 0.62Ω 0.33Ω

FUNCTIONSELECTORSWITCHASSEMBLY

C219 C217

PANEL

OFF

PANEL&FLR FLR&DEF

DEF

ILLUMINATION

INSTRUMENTILLUMINATION

181 BN/OG

C210FC210M0

BLOWERMOTOR

C191

S125

57 BK

C210MC210F

261 OG/BK

261 OG/BK

261 OG/BK

754 LG/WH

754 LG/WH

752 YE/RD

752 YE/RD

57 BK

57 BK

57 BK

S202

19 LB/RD

C218

S200

C219 C217

LOMED LO MED

HIHI

C190

C190

296 WH/VT

MODESELECTORSWITCH

12

12V

BLOWERMOTORSWITCH

0V

0V

0V

0V

FUNCTIONSELECTORSWITCHASSEMBLY

FLR

Allows operator to control speedof Blower Motor.

399 BN/YE

HOT AT ALL TIMES

BATTERYJUNCTIONBOX

364 BK/LG

C159MC159F

40A

105

364 BK/LG

181

BN/OG

261

OG/BK

261

OG/BK

S203

57 BK

570

399 BN/YE

M

Limits the amount of currentgoing to the Blower Motor,for different speeds of fan.

57 BK

G200

57 BK

G200

BK

12V (RUN)

G200

0V

0V

2 - 18



Mini-ISO Relay (Technician A)


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2 - 19

ΩΩΩΩΩ



BED157-A/VF

57 BK

G103


0V

LEFT FOGLAMP

C1520V

FOG LAMPRELAY

FOG LAMPSWITCH

C23657 BK

G200

C236

5

4

3

6

19 LB/RD

57 BK

G105

RIGHT FOGLAMP

C1590V

BATTERYJUNCTION BOX

478 TN/OGC152

477 LB/BK 478 TN/OG

C159

478 TN/OG

C136MC136F

478 TN/OG

S127

BATTERYJUNCTION BOX

DAYTIMERUNNINGLAMPS (DRL)

54

LG/YE

HOT AT ALL TIMES

54 LG/YE

C136MC136F

477 LB/BK

5

1

2

3

4

1056 DB/LG

4

20A

57 BK

S244

478

TN/OG

CENTRALJUNCTION BOX

HOT IN HEAD

8

10A

S140

1056 DB/LG

9. Technician B: Using the fog light schematic and the component testing procedure that follows,perform the tests on the fog light relay provided. Fill in the blanks with your answers.

2 - 20



Micro-ISO Relay (Technician B)


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2 - 21

ΩΩΩΩΩ



11. Technician C: Perform the pinpoint test on the starter relay and answer the questions that follow.

BED050-A/VF

2 - 22



BED070-A/VF

• Is the resistance reading 5 ohms or less.

Test Step

CHECK FOR AN OPEN RELAY COIL

• Measure the resistance between the S terminaland case ground.

Result / Action to Take

Yes

GO to A2

No

Starter relay not functioning properly.

Write your results in the space below:

• Are the resistance readings greater than10,000 ohms?

Test Step

A2 CHECK RELAY COIL FOR A SHORT CIRCUIT

• Measure the resistance between the S terminaland B terminal and between the S terminal andM terminal.


Yes

GO to A3

No



BED071-A/VF

A1

2 - 23



• Is the resistance reading less than 5 ohms?

Test Step

A3 CHECK RELAY CONTACTS FOR AN OPEN

• Connect a remote starter switch between thepower supply positive terminal and the Sterminal.

• Connect a jumper from the power supplynegative terminal and the solenoid case.

• Depress the remote starter switch.

• Measure the resistance between the B terminaland M terminal.


Yes

Starter Relay is functioning normally.

RETURN workstation to originalcondition.

No



BED072-A/VF

B+


13. What was the last pinpoint test step you performed?


2 - 24



WORKSTATION 3

2 - 25




In this workstation you will learn how some automotive components operate and how to test them. Thecomponents you will test include a sending unit, motor and diodes.

WORKSTATION 3 COMPONENT TESTING

2 - 26



1. Technician A: Perform the pinpoint test that follows on the fuel gauge sending unit and answer thequestions that follow. Refer to the fuel gauge schematic from the previous page as necessary.

• Is the resistance reading 20 ohms or less?

Test Step

CHECK SENDING UNIT AT EMPTY POSITION

• Place the sending unit at its lowest position.


Yes

GO to B2

No

Fuel sending unit not functioning properly.


B1

• Measure the resistance between the yellowwire and component ground.

• Is the resistance reading greater than 150ohms?

Test Step

CHECK SENDING UNIT AT FULL POSITION

• Place the sending unit at its full-upwardsposition.


Yes

GO to B3

No



B2

• Measure the resistance between yellow wireand component ground.

2 - 27



• Does the reading remain continuous butcontinually change as the float is moved?

Test Step

CHECK SENDING UNIT FOR AN OPEN

• Slowly move the fuel sending unit through itsfull range of travel.


Yes

Fuel Gauge Sending Unit is functioningnormally.

RETURN workstation to originalcondition.

No



B3

2. Is the component good? (circle one) YES NO

2 - 28



3. Technician B: Perform the pinpoint tests on the power window motor and answer the question thatfollows. Refer to the power window motor schematic as necessary.

2 - 29



• Is the resistance reading greater than10,000 ohms?

Test Step

CHECK POWER WINDOW MOTOR FOR ANOPEN


Yes

Power window motor not functioningproperly.

No

Go to C2.


C1

• Measure the resistance between terminal 333and 334..

• Is the resistance reading greater than10,000 ohms?

Test Step

• Measure the resistance between 333 and caseground.


Yes

Power window motor is functioningnormally

RETURN workstation to orginalcondition.

No

Power window motor is not functioningproperly.


C2 CHECK POWER WINDOW MOTOR FOR ASHORT TO GROUND

4. Is the power window motor good? (circle one) YES NO

2 - 30



5. Technician C: Perform the pinpoint tests on the blower motor and resistor, then answer the questionsthat follow. Refer to the schematic as necessary.

BED179-A/VF

2 - 31



• Is the resistance reading between 2 and 5ohms?

Test Step

CHECK BLOWER MOTOR RESISTORRESISTOR LOW CIRCUIT


Yes

GO to D2

No

Blower motor resistor assembly unit notfunctioning properly.


D1

• Measure the resistance between CKT 261 andCKT 57 of the blower motor resistor.

• Is the resistance reading between 0.8 and2 ohms?

Test Step



Yes

Go to D3

No



D2 CHECK BLOWER MOTOR RESISTOR MEDIUM 1 CIRCUIT

2 - 32



• Is the resistance reading between 0.1 and1 ohms?

Test Step

CHECK BLOWER MOTOR RESISTOR MEDIUM 2 CIRCUIT


Yes

GO to D4

No



D3


• Is the resistance greater than 10,000ohms?

Test Step

• Measure the resistance between the two blowermotor terminals.


Yes

Blower motor not functioning properly.

No

Blower motor is functioning normallyRETURN workstation to original condition.


D4 CHECK BLOWER MOTOR FOR AN OPEN CIRCUIT

6. Is the blower motor resistor good? (circle one) YES NO

7. Is the blower motor good? (circle one) YES NO

2 - 33



8. Perform the pinpoint tests below on the windshield wiper motor at your workstation and answer thequestions that follow.

BED148-A/VF

M

M

HOT IN ACCY OR RUN

2

6A

FUSEPANEL

63 RD63 RD

56 DB/OG

56 DB/OG 58 WH

58 WH

28 BK/PK

28 BK/PK 58 WH

WIPER SWITCH

B+ H L P W

WASHER SWITCHOFF HI

LO

OFF HI

LO

WINDSHIELD WIPER/WASHER SWITCH

C201

C311

LH

CPARK RUN

WIPERMOTORANDSWITCHASSEMBLY

S401

C237

941 BK/WH

941 BK/WH

941 BK/WH

57 BK

G402

WASHERPUMP

56 DB

63 RD

63 RD

28 BK

57 BK

G402

57 BK

2 - 34



• Is the current reading between 0.5 ampsand 1.5 amps?

Test Step

MEASURE CURRENT DRAW ON WIPER MOTOR (LOW SPEED)


Yes

GO to E2

No

Windshield wiper motor not functioningproperly.


E1

• Turn the power supply OFF.


Test Step Result / Action to Take

Yes

GO to E3

No



E2 MEASURE CURRENT DRAW ON WIPER MOTOR (HI-SPEED)

• Connect the negative lead of the 12V powersupply to terminal 57.

• Connect the red lead of the DMM to thepositive lead of the power supply.

• Connect the black common lead of the DMMto terminal 58 on the wiper motor.

• Turn the power supply ON and measure thecurrent.

• Turn the power supply OFF.• Connect the negative lead of the 12V power

supply to terminal 57.• Connect the red lead of the DMM to the

positive lead of the power supply.• Connect the black common lead of the DMM

to terminal 56 on the wiper motor.• Turn the power supply ON and measure the

current.

Technician B

Technician A

2 - 35




Test Step

MEASURE CURRENT DRAW ON WIPER MOTOR (GROUND)


Yes

Motor tests good. Return the workstationto its original condition.

No



E3

• Turn the power supply OFF.• Connect the positive lead of the 12V power

supply to terminal 58.• Connect the red lead of the DMM to terminal

57.• Connect the black lead of the DMM to the

negative lead of the power supply.• Turn the power supply ON and measure the

current.

Technician C

9. Is the windshield wiper motor good? (circle one) YES NO

2 - 36



BED068-A/VF

Place diode in this direction

Turn the rotary switch to diode test.Press the pushbutton for 2 seconds to toggle to the diode test function.Place the test leads as shown.Typical voltage drop is 0.5-0.8 V and causes the meter to beep.

If the diode is:Good -- the display shows OL.Shorted -- the display shows near 0 in both directions.Open -- the display shows OL in both directions.

Place diode in the other direction

Technician A, B and C

12. Is the diode good? (circle one) YES NO

10. What is the purpose of a diode?

BED067-A/VF

Barrel Diode Fuse Panel Diode Diode in Wiring Harness

11. Choose one of the diodes and test using the diode test function of the DMM and the instructionsbelow. Write the letter of the diode you are testing and your results?

2 - 37



14. Is the diode good? (circle one) YES NO

13. Choose one of the other diodes and test using the test light and power supply as shown below. Writethe letter of the diode you are testing here:

2 - 38



WORKSTATION 4

2 - 39



BED162-A/VF

3

2

1

DIRECTIONS: In this exercise you will perform various electrical repair procedures includingsoldering and crimping using the techniques you used during Day One Homework.

WORKSTATION 4 WIRE HARNESS REPAIRS

2 - 40

A

B

C

Solder Repair

Crimp/Heat Shrink Repair

• Create a solder splice (leave heat shrink tube off).

• Create a crimp splice (with heat shrink tube applied).

LESSON TWO - HOMEWORK


HOMEWORK

2 - 41



DIRECTIONS:

This homework assignment has two parts. The two parts consist of the following activities:

• Reading about the battery and charging systems and answering questions.

• Identifying expected voltage values on a headlamp schematic and a power window schematic.

Read the following information on batteries and charging systems. Answer the questions at the end ofthe reading by filling in the blanks.

BATTERY

A battery is an electrochemical device. It’s called a storage battery because it stores energy in a chemicalform. The battery stores energy for extended periods of time. It releases this energy on demand as directcurrent.

The battery provides the electricity to power all systems of the vehicle when the engine is not running.When the engine is running, the charging system supplies all the electricity to power the systems of thevehicle and the battery helps to stabilize voltage for the entire electrical system.

Batteries come in different sizes and terminal configurations to fit many different applications. Theamount of electrical energy depends on the size of the active area in the plates and the amount ofsulfuric acid in the electrolyte.

Starting the engine requires a large amount of amperes, but only for a short period of time.

The CCA rating is the number of amps that a fully-charged battery can produce at 0°F (0°C) for 30seconds while maintaining a voltage of at least 7.2 volts. The higher the CCA rating, the greater thestarting power of the battery.

Reserve Capacity (RC) defines the ability of a battery to deliver a small amount of amperage to power avehicle and its accessories with an inoperative generator. The reserve capacity rating is the length oftime a fully charged 12 volt battery at 80°F (26.7°C) can supply 25 A before the voltage falls below 10.5V. It is also a critical measurement with the high key-off current draws seen in today’s automobiles.

Ampere hour is another rating that is important to know. This rating is based on the total number ofamperes the battery can supply in a 20 hour period of even withdrawal. Accordingly, a battery rated at100 ampere/hours can supply 5 amperes for 20 hours.

Cranking Amps (CA) is a rating created for marine applications. It is similar to a CCA rating, but it israted at a higher temperature.

HOMEWORK - PART 1

2 - 42



BATTERY DRAIN TEST

As you have learned the battery provides the electricity to power all systems of the vehicle when theengine is not running. If there is a concern that causes the battery to drain while the vehicle is parked,this could reduce the available amperes when starting the vehicle, which could lead to a no-startcondition. Therefore, it is important to know how to perform a battery drain test to help ensure aproperly operating vehicle.

• Install battery disconnect switch.

• Drive the vehicle for at least 5 minutes over 30 MPH if directed by the workshop manual.

• Allow vehicle to sit for 40 minutes to 1 hour to allow modules to enter sleep mode (refer to work-shop manual for the specific time).

• Install digital multi-meter to both sides of battery disconnect switch and set to Amps position

• Open battery disconnect switch to force any drain on battery to register on Ammeter, readand record amount of current flow “draining” from battery and compare to maximum allowablespecification of 50 milliamps.

• If drain is excessive, remove fuses from fuse boxes while viewing the Ammeter until the circuitdraining the battery is identified.

2 - 43

BED178-A/VF



BED103-A/VF

+

-

I1

START ACC

RUN LOCKOFF

B5

12V 12V

12V

12V

12V(START OR RUN)

HOT AT ALL TIMES

FUSELINK

12GAGRAY

BATTERY

STATOR

FIELDREGULATOR

GENERATOR

8V

8V

12V

11

20A

BATTERYJUNCTIONBOX

IGNITIONSWITCH

12V(START OR RUN)

12V(START OR RUN)

163030A34

CENTRALJUNCTIONBOX

12V(START OR RUN)

390OHMS

2

CHARGEINDICATOR

3

INSTRUMENTCLUSTER

ROTOR

RECTIFIER

With voltage applied, generator is activated, allowingcurrent to flow from sense A circuit to generator fieldcoil. Generator generates an AC output which is con-verted to a DC output by the rectifier assembly inter-nal to generator, and is supplied to vehicle throughthe B+ terminal. The S (stator) circuit is used to feedback a voltage signal from the generator to the regu-lator. This voltage (typically half battery voltage) is used by the regulator to turn off the charge indicator lamp.

B

ASI

The charging system converts mechanical energy into electrical energy, providing current to charge thebattery and power electrical components on the vehicle. As the engine runs, the drive belt mechanicallydrives the generator. The generator converts this mechanical energy into electrical energy used to chargethe battery and support the electrical demands of the vehicle.

CHARGING SYSTEM

2 - 44



BED154-A/VF

The generator consists of the following components:

Rotor – field windings, iron fingered pole pieces, rotor shaft, and slip rings

Brush assembly – brush housing, brushes, brush springs, and brush wires

Stator – three stator windings, core, and output wires

Voltage Regulator – electronic device mounted on a generator

Rectifier– Diodes that convert AC voltage to DC voltage

Capacitor – smoothes out voltage and reduces Radio Frequency Interference

Fan and pulley – fan, spacer, pulley, lock washer, and pulley nut

Housing – drive end frame, slip ring end frame, and end frame bolts

GENERATOR COMPONENTS

2 - 45



BED155-A/VF

VOLTAGE REGULATION

To control the amount of current sent to the battery a voltage regulator is used. The voltage regulatoraccomplishes this by changing the amount of current through the rotor windings.

The change in current increases or decreases the strength of the magnetic field in the rotor. As thestrength of the magnetic field in the rotor increases, the voltage induced in the stator also increases.

Voltage regulators monitor battery voltage through a sensing circuit to determine the level of currentneeded within the rotor windings (field circuit). When battery voltage goes below a certain level, thevoltage regulator increases current in the rotor windings (field circuit). This increases the current outputof the generator and raises system voltage.

When the regulator determines that battery voltage is high enough, it lowers the current through therotor windings, lowering current output of the generator.

Voltage regulators are commonly electronic sealed units located on or in the generator and can becontrolled by the Powertrain Control Module (PCM).

2 - 46



Answer the following questions by circling the correct answers or filling in the blanks.

1. The battery provides electricity to power the systems of the vehicle when:

A. Whenever the engine is running.

B. The engine is not running.

C. The generator is charging.

D. The accessories are running.

2. Three ratings that a battery may have include:

A. Volts, Amps and Ohms

B. CCA, CA, and RC

C. Cold voltage, ambient voltage and reserve voltage

D. None of the above.

4. The maximum allowable battery drain specification is:

A. 50 amps

B. 0.5 amps

C. 0.05 amps

D. 0.005 amps

3. How long must a vehicle sit with the key in the off position before a battery drain test should beperformed?

HOMEWORK - PART 2

2 - 47



MAIN LIGHT SWITCH

INST. PANEL

DIMMERSWITCH

15 (RD/YE)

12 (LG/BK) 13 (WH/LG)

14 (BR) 19 (LB/RD) 53 (BK/LB)

38 (BK/OG) 195 (BK/OG) 54 (BK/OG)

57 (BK)

57 (BK)57 (BK)

57 (BK)

DOME

DIMMER

DOME

HEAD

B+

PANEL DIM

LOHI

FRONTPARK

FRONTPARK

LOWBEAM

HIGHBEAM


LOWBEAM

HIGHBEAM

BED159-A/VF

OFFPARK

HEAD OFFPARK

V HI_______

V LO ______

V _______

V HI_______

V LO ______

V OFF_______

V PARK_____

V HEAD_____

V _______

V MIN_______

V MAX ______

V OFF_______

V PARK_____

V HEAD_____

5. Fill in the expected voltage values in the spots indicated on the schematic using all of the headlampswitch positions.

2 - 48



6. Fill in the expected voltage values in the spots indicated on the schematic using the switch positionsidentified.

BED120-AA/VF

MASTER PASSENGER

MASTER PASSENGER

2 - 49



NOTES

INSTRUCTOR LED DEMO - LESSON THREE


INSTRUCTOR - LED DEMONSTRATION

3 - 1



BED157-A/VF

57 BK

G103


0V

LEFT FOGLAMP

C1520V

FOG LAMPRELAY

FOG LAMPSWITCH

C23657 BK

G200

C236

5

4

3

6

19 LB/RD

57 BK

G105

RIGHT FOGLAMP

C1590V

BATTERYJUNCTION BOX

478 TN/OGC152

477 LB/BK 478 TN/OG

C159

478 TN/OG

C136MC136F

478 TN/OG

S127

BATTERYJUNCTION BOX

DAYTIMERUNNINGLAMPS (DRL)

54

LG/YE

HOT AT ALL TIMES

54 LG/YE

C136MC136F

477 LB/BK

5

1

2

3

4

1056 DB/LG

4

20A

57 BK

S244

478

TN/OG

CENTRALJUNCTION BOX

HOT IN HEAD

8

10A

S140

1056 DB/LG

DIRECTIONS: During this demonstration, you will trace power flow on three different schematics.You will use yellow to indicate loads, red to indicate power, black for ground, blue for power-sideswitched circuits, green for ground-side switched circuits.

INSTRUCTOR-LED DEMONSTRATION

3 - 2



MAIN LIGHT SWITCH

INST. PANEL

DIMMERSWITCH

15 (RD/YE)

12 (LG/BK) 13 (WH/LG)

14 (BR) 19 (LB/RD) 53 (BK/LB)

38 (BK/OG) 195 (BK/OG) 54 (BK/OG)

57 (BK)

57 (BK)57 (BK)

57 (BK)

DOME

DIMMER

DOME

HEAD

B+

PANEL DIM

LOHI

FRONTPARK

FRONTPARK

LOWBEAM

HIGHBEAM


LOWBEAM

HIGHBEAM

BED158-A/VF

OFFPARK

HEAD OFFPARK

3 - 3


March, 2006 Basic Electrical Diagnosis3 - 4


LESSON THREE - WORKSTATION 1

WORKSTATION 1

3 - 5



DIRECTIONS: In this workstation you will become familiar with battery and charging systemanalyzers and use them to properly perform tests on a normally operating system. In this workstationyou will perform the following tests:

• Battery test using the Micro 490

• Generator on-vehicle tests using the SABRE/ARBST

• Battery Drain Test using the DMM

1. Locate the Visual Inspection instructions within the Workshop Manual and list below a few of themechanical and electrical tests you should perform when diagnosing a battery or charging systemconcern

2. Using the Workshop Manual, list the tool that is used to perform the battery condition test.

3. Perform the battery condition test. Use the instructions provided by the equipment manufacturer.What information had to be entered in order to perform the test?

4. What are the results of the test?

5. If the test indicates a faulty battery and the vehicle is still under warranty what information must beretrieved from the tool?

lacinahceM lacirtcelE

WORKSTATION 1 BATTERY AND CHARGING SYSTEMS TESTING

3 - 6



6. With engine running at 2000 rpm and the headlamps and heater blower on, perform a voltage droptest between the battery negative terminal and the generator housing. Record your reading:

8. Using the Workshop Manual, list the different generator on-vehicle tests that can be performed andexplain what each test checks for.

9. Perform the generator on-vehicle tests according to the equipment manufacturer’s instructions. Listbelow the maximum current and voltage.

Maximum current output:

Maximum voltage output:

7. With engine running at 2000 rpm and the headlamps and heater blower on, perform a voltage droptest between the battery positive terminal and the output terminal of the generator. Record yourreading:

3 - 7



10. Number the steps required to perform the battery drain test in the correct order.

A. Allow vehicle to sit for 40 minutes to 1 hour to allow modules to enter sleep mode.

B. Install battery disconnect switch.

C. Install digital multi-meter to both sides of battery disconnect switch and set to Amps position

D. If drain is excessive, remove fuses from fuse boxes while viewing the Ammeter until the circuit draining the battery is identified

E. Open battery disconnect switch to force any drain on battery to register on Ammeter, readand record amount of current flow “draining” from battery and compare to maximumallowable specification of 50 milliamps.

F. Drive the vehicle for at least 5 minutes over 30 MPH if directed by the workshop manual

11. Explain why it is necessary to wait a given amount of time before performing the drain test.

3 - 8



12. Perform the battery drain test. Assume the vehicle has already been driven and been allowed to sitthe appropriate amount of time. Record your reading below

13. What is the specification for this vehicle?

14. Is your reading within specification?

(circle one) YES NO

15. What would you do next if your readings were not within specification?


3 - 9



NOTES



WORKSTATION 2

3 - 11



MAIN LIGHT SWITCH

INST. PANEL

DIMMERSWITCH

15 (RD/YE)

12 (LG/BK) 13 (WH/LG)

14 (BR) 19 (LB/RD) 53 (BK/LB)

38 (BK/OG) 195 (BK/OG) 54 (BK/OG)

57 (BK)

57 (BK)57 (BK)

57 (BK)

DOME

DIMMER

DOME

HEAD

B+

PANEL DIM

LOHI

FRONTPARK

FRONTPARK

LOWBEAM

HIGHBEAM


LOWBEAM

HIGHBEAM

BED158-A/VF

OFFPARK

HEAD OFFPARK

DIRECTIONS: In this workstation you will learn how a basic headlamp system operates and how todiagnose basic electrical concerns in a headlamp circuit using a DMM. Using the schematic thatfollows, wire the headlamp board to the 12V battery pack and connect the components using jumperwires. Test the board for correct operation.

WORKSTATION 2 HEADLAMP CIRCUIT

3 - 12



MAIN LIGHT SWITCH

INST. PANEL

DIMMERSWITCH

15 (RD/YE)

12 (LG/BK) 13 (WH/LG)

14 (BR) 19 (LB/RD) 53 (BK/LB)

38 (BK/OG) 195 (BK/OG) 54 (BK/OG)

57 (BK)

57 (BK)57 (BK)

57 (BK)

DOME

DIMMER

DOME

HEAD

B+

PANEL DIM

LOHI

FRONTPARK

FRONTPARK

LOWBEAM

HIGHBEAM


LOWBEAM

HIGHBEAM

BED159-A/VF

OFFPARK

HEAD OFFPARK

V HI_______

V LO ______

V _______

V HI_______

V LO ______

V OFF_______

V PARK_____

V HEAD_____

V _______

V MIN_______

V MAX ______

V OFF_______

V PARK_____

V HEAD_____

1. Technician A: Using the following schematic, measure and record voltage readings at the spotsindicated.

2. Do the values you measured agree with your homework?

(circle one) YES NO

NOTE: If you answered no, see the instructor.

3 - 13



Turn off power to the circuit. Remove the wire connected to CKT 57 (ground) from the left side of theheadlamp board. Turn on power to the circuit.

3. Technician B: Using the following schematic, measure and record voltage readings at the spotsindicated.

3 - 14

MAIN LIGHT SWITCH

INST. PANEL

DIMMERSWITCH

15 (RD/YE)

12 (LG/BK) 13 (WH/LG)

14 (BR) 19 (LB/RD) 53 (BK/LB)

38 (BK/OG) 195 (BK/OG) 54 (BK/OG)

57 (BK)

57 (BK)57 (BK)

57 (BK)

DOME

DIMMER

DOME

HEAD

B+

PANEL DIM

LOHI

FRONTPARK

FRONTPARK

LOWBEAM

HIGHBEAM


LOWBEAM

HIGHBEAM

BED181-A/VF

OFFPARK

HEAD OFFPARK

V HI_______

V LO ______

V OFF V PARKV LOV HI

V HI_______

V LO ______

V OFF_______

V PARK_____

V HEAD_____

V _______

V MIN_______

V MAX ______

V OFF_______

V PARK_____

V HEAD_____



4. Explain why the bulbs light as they do in the low-beam position.

5. What type of fault exists?

A. High resistanceB. OpenC. Short to groundD. Short to power

3 - 15



Turn off power to the circuit. Reconnect the grounds that were removed. Replace the headlamp bulb onthe right side of the headlamp board with the other bulb provided at the workstation. Turn on power tothe circuit.

6. Technician C: Using the following schematic, measure and record voltage readings at the spotsindicated.

MAIN LIGHT SWITCH

INST. PANEL

DIMMERSWITCH

15 (RD/YE)

12 (LG/BK) 13 (WH/LG)

14 (BR) 19 (LB/RD) 53 (BK/LB)

38 (BK/OG) 195 (BK/OG) 54 (BK/OG)

57 (BK)

57 (BK)57 (BK)

57 (BK)

DOME

DIMMER

DOME

HEAD

B+

PANEL DIM

LOHI

FRONTPARK

FRONTPARK

LOWBEAM

HIGHBEAM


LOWBEAM

HIGHBEAM

BED159-A/VF

OFFPARK

HEAD OFFPARK

V HI_______

V LO ______

V _______

V HI_______

V LO ______

V OFF_______

V PARK_____

V HEAD_____

V _______

V OFF_______

V PARK_____

V HEAD_____

3 - 16



Remove the bulb at fault point B and reinstall the original bulb. Remove all jumper wires andrestore the workstation to the condition you found it.

7. Explain why the bulbs light as they do in the low-beam position.



3 - 17



NOTES



WORKSTATION 3

3 - 19



POWER WINDOW CIRCUIT

DIRECTIONS: In this workstation, you will learn how a basic power window system operates and howto diagnose basic electrical concerns in a power window circuit using a DMM. Wire the power windowmotor circuit. Be sure to include the fault box and set the fault box switch to the No Fault position.

BED225-A/VF

334

333

57

314

313

400

333 333

334 334

57 400 314 313

31331440057

A

FE-18

B

C

NO FAULT

+

-

MASTER POWER WINDOW SWITCH

DRIVERS SIDE PASS SIDE

314

400

313

333

334

POWER WINDOW SWITCH

1. Operate the power window switches in each mode to verify proper operation. Do the windows workfrom the master and passenger window switches in both up and down positions?

(Circle one) YES NO

NOTE: If you answered NO, see the instructor.

WORKSTATION 3 POWER WINDOW CIRCUIT

3 - 20



Power Window Circuit

The power windows only operate with the ignition switch in the ACC or RUN position. Power issupplied through a circuit breaker in the fuse junction panel. At rest, both contacts in the master windowcontrol switch are connected to ground.

Pressing the DOWN side of the master window control switch connects the DOWN lead in the windowmotor to power. The UP lead is connected to ground.

Pressing the UP side of the master window control switch connects the UP lead in the window motor topower. The DOWN lead is connected to ground.

The right front window switch is wired in series between the master window control switch and the rightfront window motor.

3 - 21



2. Using the schematic of the power window circuit, measure the available voltage at the labeled loca-tions.

BED120-AA/VF

MASTER PASSENGER

MASTER PASSENGER


(Circle one) YES NO


3 - 22



4. Perform a voltage drop test on the right front window motor circuits listed and record your values.

NOTE: * Only test the circuits for the right front window motor.

tnemerusaeMporDegatloV

tnorFthgiRwodniWretsaMnoitisoPhctiwSlortnoC

lortnoCwodniWregnessaPnoitisoPhctiwS

tiucriC pU nwoD pU nwoD

75

004

413

313

333*

433*

3 - 23



5. What symptom is present.

6. Measure the available voltage at the locations shown in the schematic and record your values.

BED120-AA/VF

MASTER PASSENGER

MASTER PASSENGER

Technician A: Set fault box switch to Fault A and operate the right front window motor using bothwindow control switches.

3 - 24




8. Which circuit is at fault.








75

004

413

313

333*

433*

3 - 25





Technician B: Set fault box switch to Fault B and operate the right front window motor using bothwindow control switches.

BED120-AA/VF

MASTER PASSENGER

MASTER PASSENGER

3 - 26












75

004

413

313

333*

433*

3 - 27





Technician C: Set fault box switch to Fault C and operate the right front window motor using bothwindow control switches.

BED120-AA/VF

MASTER PASSENGER

MASTER PASSENGER

3 - 28













75

004

413

313

333*

433*

3 - 29



NOTES



WORKSTATION 4

3 - 31



DIRECTIONS: In this workstation you will learn how to use both paper-based and electronic WiringDiagrams.

PART 1

Using the paper-based Wiring Diagram for a 2005 Econoline, answer the following questions.

1. Match the cell number with the appropriate letter of the description.

1-1

2-1

3-1

4-1

5-1

9-1

2. Refer to page 4-4. Match the letter in the art with the appropriate desctription.

AB

D

C

EF

Connector number

Wire insulation color

Wire size (gauge)

Ground number

Circuit number

Connector pin number

A. IndexB. SymbolsC. IntroductionD. Connector repair proceduresE. Table of contentsF. Wire harness overview

WORKSTATION 4 WIRING DIAGRAM NAVIGATION

3 - 32

329 18 PK

57 20 BK

4 C100

G100



4. Match the connector, splice or ground numbers with the appropriate location description.

C234

C516

G401S375

G105

C805

A. Passenger door, right rearB. Behind rear seatsC. Instrument panel and consoleD. Engine compartmentE. Driver doorF. From instrument panel to rear seat, below door trim panel

3. Refer to page 4-6. Write the number associated with each section of the vehicle in the space providedin the art.

3 - 33



Using the paper-based Wiring Diagram for a 2005 Econoline, answer the following questions regardingthe headlamp system.

7. Where is fuse F2.10 located?

8. What is the amp rating of Fuse F2.10?

9. Under what conditions does Fuse F2.10 have power?

10. Why is the box around the Central Junction Box dashed?

6. What is the difference between cell 85-1 and 85-2?

5. What cell contains the schematic for the headlamps?

PART 2 - WIRING DIAGRAM NAVIGATION

3 - 34



BED169-A/VF

11. Notice the dashed wire representing circuit 195. A dashed wire indicates?

A. The wire has white dashes painted on it for easy identification.B. This wire connects to other components not shown on this page.C. This wire is protected by a shield to prevent electromagnetic interference.D. This wire is hot at all times.

12. Where do you go if you need more information about the Central Junction Box?

13. Using the Power Distribution section, identify the components that receive power through fuseF2.10?

3 - 35



14 Refer to page 85-1. Where would you find Fuse 2.30, 2.25, and 2.31?

A. Battery Junction BoxB. Central Junction BoxC. Auxiliary Relay Box

15. Circle the location of Fuse 2.30, 2.25, and 2.31 on the illustration shown.

16. If F2.30 were removed, what component(s) would not operate? (Circle all that apply)

Daytime Running Lights Left High Left Low Right High Right Low

A. Component Location Charts

B. Connector Views

C. Component Testing

D. Component Location View

17. Match the cell numbers with the appropriate letter of the description.

149-1150-1

151-1

152-1

3 - 36



20. Find the connector view of C144. How many wires are in connector C144?

21. Using cell 152, what page shows the location of C144 and what are the grid coordinates?

18. What Wiring Diagram page would you use to test the Main Light Switch?

22. Circle the letter of the arrow that points to C144 in the illustration below.

19. How many wires are shown in connector C144 on page 85-1?

3 - 37



24. Circle the approximate location of splice S164 in the illustration below.

23. Where is splice S164 located?

3 - 38



Use the electronic Wiring Diagram to answer the following questions about a 2005 Econoline.

a. Select Service Publications, then Wiring Diagrams from the menu.

b. Select 2005 E-150 from the selection menu, then “View Content”.

c. Select the cell that takes you to the schematic of the Headlamp System.

25. Is the Cell number for the headlamp system the same as the paper manual?

(circle one) YES NO

26. Compare this schematic to the paper manual. List any differences.

27. Place your mouse pointer over each of the various items in the gray selection menu area. Identify theicons below and describe their function:

28. Click on the “Search” icon.

What selections are available from the search drop down menu?

PART 3 - WIRING DIAGRAM NAVIGATION

3 - 39



Vehicle: 2005 Econoline

a. Select the cell 85-1

b. Click on the blue, underlined text for connector C205.

32. Why are there two circuits in Pin D1?

30. What display choices are available when you select the connector?

a. Select Connector Face.

31. Circle the headlamp flash to pass pin in the illustration below.

29. From the drop down menu select “Components”. Select the letter H, then select Headlamp, left(13008), click “SEARCH”. Is 085-001 available from the search?

(circle one) YES NO

3 - 40

B2

B1

IGN

DN D1

RH

I

D2

LESSON THREE - HOMEWORK


HOMEWORK

3 - 43

LESSON THREE: HOMEWORK

April, 2008 Basic Electrical Diagnosis

BED129-A/VF

Contains a reversible motor whichlocks or unlocks door according todirection of current flow.

POWERWINDOWSPAGE 100-1

POWERWINDOWSPAGE 100-1

POWERDISTRIBUTIONPAGE 13-11,13-12

10A

LEFT DOORLOCK SWITCH

151- 16- A1

296 W/P

S317

4 C215

ACC

HOT IN ACC OR RUN

33

When switchmoved, voltage andcurrent directed inappropriate direc-tion to lock/unlockdoors.

PRIMARYJUNCTIONBLOCKPAGES 13-8,13-11

C514

SEE POWER DISTRIBUTIONPAGE 13-8

517 BK/W

S314

21 C215

SEAT/LOCK

20A

C226

HOT IN ACC OR RUN

C614

57 BK

C514

7

7

6

3

14

C510

25

296 W/P

S498

7

6

296

W/P

UNLOCK LOCK

M

3

1

C614

4

C301

25

RIGHT DOORLOCK SWITCH

151- 16- A6

517

BK/W

296 W/P12V

LEFT DOORLOCK ACTUATOR

0V (LOCK)12V (UNLOCK)

151- 16- E1

SEE GROUNDSPAGE 10-12

296

W/P

0V 0V 0V

57 BK

G301

G301GROUND BUS

POWERDISTRIBUTIONPAGE 13-11

S602

296 W/P

517 BK/W

517 BK/W

0V

C300

G300

G300GROUND BUS

S603

GROUNDSPAGE 10-16

C610

M

RIGHT DOORLOCK ACTUATOR

0V (LOCK)12V (UNLOCK)

151- 16- B9

S502

119 PK/Y

117 PK/BK118 PK/O

120 PK/LG

0V (UNLOCK)12V (LOCK)

57 BK 57 BK

118 PK/O117 PK/BK

0V (UNLOCK)12V (LOCK)

57 BK

57

BKS499

UNLOCK LOCK

12V 12V (ACC OR RUN) 12V (ACC OR RUN)

When switchmoved, voltageand current di-rected in appropri-ate direction tolock/unlock doors.

C.B.

117 PK/BK118 PK/O

119 PK/Y

151- 12- C1 151- 12- C1

A

B

C

D

E

HOMEWORK

DIRECTIONS: Use the following schematics to diagnose the listed concerns. Circle the letters of allof the circuits or components that could cause the concern.

1. Concern: The left door lock actuator doesn’t work from either switch. The right front actuatorworks properly.

3 - 44



2. Concern: The blower motor operates when the switch is in the HI position. The blower motor doesnot operate when the switch is in any other position.

C

D

A

H

B

F

G

E

3 - 45



3. Concern: Both fog lamps are inoperative. All other exterior lights work properly.

E43

Fog lamp, left front

P93

Battery Junction

Box (BJB)

C2055

N113

Main light switch

0) Off

1) Park

7) Head

70 1

C2053

S110

G103

18 BK57

P93

Battery Junction

Box (BJB)

30) Hot at all times

30

F1.3315A

18 BN14

K337

Fog lamp isolation

relay

C1038

C1038

3

4

2

1

30

F1.3120A

P93

Battery Junction

Box (BJB)K26

Fog lamp relay

C1007

C1007

1

2

3

5

18 LG/YE54

S119

G103

20 BK57

C1522

C1521

18 TN/OG478

E42

Fog lamp, right front

S123

G105

20 BK57

C1621

C1622

18 TN/OG478

S122

01

N114

Fog lamp switch

0) Off

1) On

18 TN/OG478

18 TN/OG478

8

18 TN/OG478

6

20 LB/BK477

C1449

22 LB/BK477

3

22 LB/RD19

C2405

413–00–00–1

S203

G201

C2404

22 BK57

S215

S121

417–01–00–1

18 OG/LG474

18 BN1418 LG/BK12

Instrument Cluster and

Panel Illumination

BED153-A/VF

B

C

D

E

A

3 - 46



DIRECTIONS: Read the following information on the starting system and answer the questions.

BED050-A/VF

The starting system uses electrical energy stored in the battery to engage a starting motor and turn theengine. The starting system contains the following components:

• Battery: Provides stored electrical energy for the starting system.

• Cable and wires: Transfers electrical energy to the starter.

• Ignition switch: Enables the driver to control starter operation.

• Neutral safety switch or clutch interlock switch: Prevents the starting system from engaging if thevehicle is not in Park or Neutral.

• Starter relay, ISO or fender mounted: Transfers electrical current to the starter.

• Starter solenoid: Transfers electrical current to the motor and engages the starter drive.

• Starter motor: High torque motor used to turn the engine’s flywheel ring gear.

• Starter drive and flywheel ring gear: Engages and turns the engine

HOMEWORK - PART 2

3 - 47



The starter motor contains a starter drive that engages the flywheel and rotates the engine. The starterdrive consists of a pinion gear set that engages a ring gear on the flywheel of the engine.

The pinion gear must mesh with the flywheel ring gear before rotation occurs to prevent damage. Theteeth of the pinion gear are tapered to assure smooth engagement with the flywheel ring gear.

The starter drive has an overrunning clutch that engages the pinion gear with the flywheel as the startermotor turns. The overrunning clutch freewheels when the engine takes over and prevents the startermotor from being damaged.

Since the starter motor draws such high current from the battery, there are heavy cables (wires) betweenthe battery and the starter motor. The cables also have to be as short as possible to prevent voltage dropacross the cable. The starting system incorporates relays and solenoids to control the high current.

HOMEWORK - PART 2

3 - 48



4. What is the purpose of the starting system.

DIRECTIONS: Answer the following questions by filling in the blanks.

5. What are the two types of starter relays.

6. What does the neutral safety switch prevent.

7. Why do the starting system cables and wires need to be as short as possible?

8. What two components of the starting system transfer and control high current?

9. Why does the starter drive need an overrunning clutch?

3 - 49



10. In the blanks provided on the schematic, fill in the voltage values you would expect to find at eachlocation in a properly operating circuit. Use the switch positions listed next to the blanks.

BED148-B/VF

M

M

HOT IN ACCY OR RUN

2

6A

FUSEPANEL

63 RD63 RD

56 DB/OG

56 DB/OG 58 WH

58 WH

28 BK/PK

28 BK/PK 58 WH

WIPER SWITCH

B+ H L P W

WASHER SWITCHOFF HI

LO

OFF HI

LO


C201

C311

LH

CPARK RUN


S401

C237

941 BK/WH

941 BK/WH

941 BK/WH

57 BK

G402

WASHERPUMP

56 DB

63 RD

63 RD

28 BK

57 BK

G402

57 BK

3 - 50


INSTRUCTOR-LED DEMONSTRATION - LESSON FOUR

INSTRUCTOR - LED DEMONSTRATION

4 - 1

INSTRUCTOR-LED DEMONSTRATION - LESSON FOUR


INSTRUCTOR-LED DEMONSTRATION NOTES

4 - 2


LESSON FOUR - WORKSTATION 1

WORKSTATION 1

4 - 3



DIRECTIONS: In this workstation you will learn to diagnose a basic electrical concern.

Technician A: Diagnose symptom A on the repair order. All technicians in the team should answer thefollowing questions as a group.

1. What is the symptom?

2. What system(s) may be at fault?

petStseT stluseR

3. What component(s) could be the cause of this concern?

Technicians B and C: Use the spaces below to record what actions/tests Technician A performed andthe result of each.

WORKSTATION 1 ON-VEHICLE DIAGNOSIS

4 - 4



4. What component is at fault?

5. What is the cause of the concern?


6. What service actions would you take to resolve the concern?

Technician B: Diagnose symptom B on the repair order.

All technicians in the team should answer the following questions as a group.




4 - 5




petStseT stluseR


Technicians A and C: Use the spaces below to record what actions/tests Technician B performed andthe result of each.


A. High resistance

B. Open

C. Short to ground

D. Short to power


4 - 6



WORKSTATION 2

4 - 7




Technician C: Diagnose symptom A on the repair order. All technicians in the team should answer thefollowing questions as a group.



petStseT stluseR


Technicians A and B: Use the spaces below to record what actions/tests Technician A performed andthe result of each.


4 - 8







Technician B: Diagnose symptom B on the repair order.

All technicians in the team should answer the following questions as a group.




4 - 9




petStseT stluseR


Technicians A and C: Use the spaces below to record what actions/tests Technician B performed andthe result of each.


A. High resistance

B. Open

C. Short to ground

D. Short to power


4 - 10



WORKSTATION 3

4 - 11



DIRECTIONS: In this workstation you will learn to diagnose a starting system concern using a DMM.

1. Trace the starting system power flow from the fuses through the components to ground on the schematicthat follows using colored markers. Use yellow to indicate loads, red for power, blue for power-sideswitched circuits, green for ground-side switched circuits, and black for ground. This vehicle isequipped with an automatic transmission.

WORKSTATION 3 STARTING SYSTEM DIAGNOSIS

4 - 12

BED127-A/VF

PK329

12V (START)

RD/WH1093

PK329

33 WH/PK

3333 WH/PK

WH/PK

P

R2

D

P

R N

10

1

HOT IN ALL TIMES

DIGITAL TRANSMISSIONRANGE (DTR) SENSORPAGES 29-3, 30-3REFER TO SECTION 307-01OF THE WORKSHOPMANUAL FOR TESTING

AUTOMATICTRANSMISSION

MANUALTRANSMISSION

PK329

12

57 BK

+

–

M

RD

STARTERMOTOR/SOLENOID

BATTERY

2037

MANUALTRANSMISSION

CHARGINGSYSTEM

85

86

30

87 87A

RD2037

"S" TERMINAL

5

50A

HOT AT ALL TIMES

RD/WH1093

BK/GN

BK/GN

37

STARTERRELAY

*12V

37


0V

0V

57 BK

57 BK

0

LB113

LB113

LB113

LB113

LB113

OFF

START

ST 11

RUNLOCK

ACC



BED127-B/VF

PK329

12V (START)

1093

PK329

3333 WH/PK

33 WH/PK

WH/PK

P

R2

D

P

R N

10

1

DIGITAL TRANSMISSIONRANGE (DTR) SENSORPAGES 29-3, 30-3REFER TO SECTION 307-01OF THE WORKSHOPMANUAL FOR TESTING


MANUALTRANSMISSION

PK329

12

57 BK

+

–

M

RD

STARTERMOTOR/SOLENOID

BATTERY

2037

MANUALTRANSMISSION

CHARGINGSYSTEM

85

86

30

87 87A

RD2037

"S" TERMINAL

5

50A

HOT AT ALL TIMES

RD/WH

RD/WH

1093

BK/GN

BK/GN

37

STARTERRELAY

*12V

37


0V

0V

57 BK

57 BK

0

LB113

LB113

LB113

LB113

LB113

HOT IN ALL TIMES

OFF

START

ST 11

RUNLOCK

ACC

2. In the blanks provided on the schematic, fill in the voltage values you would expect to find at eachlocation in a properly operating circuit when the ignition switch is turned to the START position

4 - 13



4. Locate the instructions to perform the starter system component tests. What section of the WorkshopManual is this information located?

5. List below the recommended component tests?

3. Locate the Visual Inspection Instructions for the starting system within the Engine Group of theWorkshop Manual for a 2008 Ranger and list below a few of the mechanical and electrical tests youshould perform.

lacinahceM lacirtcelE

4 - 14



Voltage Test – Starter Motor Relay Circuit

6. Technician A: Using the starting system schematic shown at the beginning of this workstation,terminal location chart and the procedure that follows, perform voltage tests at the starter relay. Fillin the blanks with your answers.

tseTottiucriC retemtloVtcennoCslanimreTot

lliWtiucriCdooGAetacidnI setacidnItseTruoY

lioCyaleRotrewoPothctiwsnoitingI

TRATS)delbasidnoitingI(

58otdaelevitisoPdna

otdaelevitageNdnuorg

dnuorGlioCyaleRothctiwsnoitingI


68otdaelevitisoPdna


yaleRotrewoPtcatnoC

03otdaelevitisoPdna


tcatnoCyaleRytiunitnoCothctiwsnoitingI


78otdaelevitisoPdna


7. If a higher than expected voltage reading is obtained between terminal 86 and ground, what does thisindicate?

4 - 15



d. Move the DMM negative (-) lead to the starter solenoid M-terminal and repeat the test. Recordyour reading:

Voltage Drop Test – Starter Motor Feed Circuit

8. Technician B: Perform a voltage drop test on the starter motor feed circuit using the procedure thatfollows:

a. Disable the ignition system.

b. Connect the positive (+) lead of the DMM to the battery positive (+) post. Connect the negative(-) lead to the solenoid B-terminal.

c. Attempt to crank over the engine while observing the DMM. The DMM reading should be 0.5volts or less. Record your reading:

4 - 16

BED095-BB

+

-

BS

M



9. What is the range for an acceptable voltage drop reading?

10. What does a higher than expected voltage drop reading indicate?

11. What components could be suspect if you received a higher than expected voltage drop reading atthe B terminal?

4 - 17



c. Attempt to crank over the engine while observing the DMM and read the voltage. The readingshould be 0.2 volts or less. Record your reading:

Voltage Drop Test – Starter Motor Ground Circuit

12. Technician C: Perform a voltage drop test on the starter motor ground circuit following the instruc-tions below:*

a. Disable the ignition system.

b. Connect the positive (+) lead of a DMM to the starter motor housing as shown in the previousillustration. The connection must be clean and free of rust or grease. Connect the negative (-)lead to the negative (-) battery terminal.

4 - 18

BED095-A/VF

+

-

BS

M



13. What is the range for an acceptable voltage drop reading on the ground side?

14. What does a higher than expected voltage drop reading indicate?

15. What components could be suspect if you received a higher than expected voltage drop reading onthe ground side?

4 - 19



NOTES



WORKSTATION 4

4 - 21



DIRECTIONS: In this workstation you will learn to diagnose basic electrical concerns in a wipermotor circuit. Wire the wiper motor circuit as shown below. Be sure to include the fault box and set thefault box switch to the No Fault position.

BED226-A/VF

63WIPER MOTOR

WIPER SWITCH

58 56 28 57

28 58 63 56

+

-

58 56 28 57

57285658

A

FE-18

BC

NO FAULT

1. Operate the wipers, using the wiper switch, in each mode to verify proper operation. Do the wiperswork in HI speed, LO speed, and PARK (when the switch is turned off)?

(Circle one) YES NO


WORKSTATION 4 WIPER SYSTEM DIAGNOSIS

4 - 22



BED148-A/VF

M

M

HOHOT IN AT IN ACCY OR RCCY OR RUNUN

2

6A

FUSEPANEL

63 RD63 RD

56 DB/OG

56 DB/OG 58 WH

58 WH

28 BK/PK

28 BK/PK 58 WH

WIPER SWITCH

B+ H L P W

WASHER SWITCHOFF HI

LO

OFF HI

LO


C201

C311

LH

CPARK RUN


S401

C237

941 BK/WH

941 BK/WH

941 BK/WH

57 BK

G402

WASHERPUMP

56 DB

63 RD

63 RD

28 BK

57 BK

G402

57 BK

Windshield Wiper System

The windshield wiper system will only operate with the ignition switch in the ACC or RUN position.Power is supplied through a circuit breaker in the fuse junction panel to the wiper switch

Selecting the LO position on the wiper switch connects the L brush in the wiper motor to power. The Cbrush on the wiper motor is always grounded.

Selecting the HI position on the wiper switch connects the H brush in the wiper motor to power. Thecurrent path in the armature winding is changed, causing the motor to run faster.

An integral park switch is mechanically linked to the two-speed electric windshield wiper motor. Thepark switch is cycled from RUN to PARK at the end of the down stroke of the wiper blades.

When the wiper switch is moved to the OFF position, power is maintained on the L brush of the wipermotor through the wiper switch and the wiper motor park switch in the RUN position. The wiper motorwill continue at low-speed until the wiper motor park switch grounds the L brush in the PARK position,stopping the motor with the wiper blades at the end of their down stroke.

4 - 23



2. Using the schematic of the wiper circuit, measure the available voltage at the labeled locationsthrough all the wiper switch positions.

BED148-B/VF

M

M


2

6A

FUSEPANEL

63 RD63 RD

56 DB/OG

56 DB/OG 58 WH

58 WH

28 BK/PK

28 BK/PK 58 WH

WIPER SWITCH

B+ H L P W

WASHER SWITCHOFF HI

LO

OFF HI

LO


C201

C311

LH

CPARK RUN


S401

C237

941 BK/WH

941 BK/WH

941 BK/WH

57 BK

G402

WASHERPUMP

56 DB

63 RD

63 RD

28 BK

57 BK

G402

57 BK


(Circle one) YES NO

NOTE: If you answered no, see the instructor.

4 - 24



4. Perform a voltage drop test on the circuits listed in the table below and record your values.

5. Connect the DMM in series in circuits 56, 58, and 57, one at a time. Take current measurements withthe switch in LO and HI positions, and record your readings in the table below. *


tiucriC ffO OLrepiW IHrepiW

65

85

82

36

75

tnemerusaeMtnerruC

tiucriC OLrepiW IHrepiW

65

85

75

4 - 25



BED148-B/VF

M

M


2

6A

FUSEPANEL

63 RD63 RD

56 DB/OG

56 DB/OG 58 WH

58 WH

28 BK/PK

28 BK/PK 58 WH

WIPER SWITCH

B+ H L P W

WASHER SWITCHOFF HI

LO

OFF HI

LO


C201

C311

LH

CPARK RUN


S401

C237

941 BK/WH

941 BK/WH

941 BK/WH

57 BK

G402

WASHERPUMP

56 DB

63 RD

63 RD

28 BK

57 BK

G402

57 BK

Technician A: Set the fault box switch to Fault A and operate the wiper motor using both HI and LOwiper switch positions.

6. What symptom is present?.


4 - 26




9. Which circuit is at fault?

10. Connect the DMM in series in circuit 57. Take current measurements with the switch in both the LOand HI positions, and record your readings.


A. High resistance

B. Open

C. Short to ground

D. Short to power



65

85

82

36

75

4 - 27



BED148-B/VF

M

M


2

6A

FUSEPANEL

63 RD63 RD

56 DB/OG

56 DB/OG 58 WH

58 WH

28 BK/PK

28 BK/PK 58 WH

WIPER SWITCH

B+ H L P W

WASHER SWITCHOFF HI

LO

OFF HI

LO


C201

C311

LH

CPARK RUN


S401

C237

941 BK/WH

941 BK/WH

941 BK/WH

57 BK

G402

WASHERPUMP

56 DB

63 RD

63 RD

28 BK

57 BK

G402

57 BK

Technician B: Set fault box switch to Fault B and operate the wiper motor using both HI and LO switchpositions.

12. What symptom is present?


4 - 28







A. High resistance

B. Open

C. Short to ground

D. Short to power



65

85

82

36

75

4 - 29



BED148-B/VF

M

M


2

6A

FUSEPANEL

63 RD63 RD

56 DB/OG

56 DB/OG 58 WH

58 WH

28 BK/PK

28 BK/PK 58 WH

WIPER SWITCH

B+ H L P W

WASHER SWITCHOFF HI

LO

OFF HI

LO


C201

C311

LH

CPARK RUN


S401

C237

941 BK/WH

941 BK/WH

941 BK/WH

57 BK

G402

WASHERPUMP

56 DB

63 RD

63 RD

28 BK

57 BK

G402

57 BK

Technician C: Set fault box switch to Fault C and operate the wiper motor using both HI and LOswitch positions.

18. What symptom is present?


4 - 30







A. High resistance

B. Open

C. Short to ground

D. Short to power




65

85

82

36

75

4 - 31



NOTES


LESSON FIVE - WORKSTATION 1

WORKSTATION 1

5 - 1




Technician A: Diagnose symptom A on the repair order. All technicians in the team should answer thefollowing questions as a group.



petStseT stluseR


Technicians B and C: Use the spaces below to record what actions/tests Technician A performed andthe result of each.


5 - 2








5 - 3



NOTES



WORKSTATION 2

5 - 5




Technician B: Diagnose symptom A on the repair order. All technicians in the team should answer thefollowing questions as a group.



petStseT stluseR


Technicians A and C: Use the spaces below to record what actions/tests Technician A performed andthe result of each.


5 - 6








5 - 7



NOTES



WORKSTATION 3

5 - 9



DIRECTIONS: In this workstation you will diagnose a starting system concern using a 2006 RangerWorkshop Manual and a DMM. Answer the following questions as a group.



3. What components or circuits could be the cause of the concern?

4. Diagnose the concern and use the spaces below to record what actions/tests you performed and theresult of each.

petStseT stluseR

WORKSTATION 3 STARTING SYSTEM DIAGNOSIS

5 - 10





A. High resistance

B. Open

C. Short to ground

D. Short to power



5 - 11



NOTES



WORKSTATION 4

5 - 13



DIRECTIONS: In this workstation you will diagnose an electrical concern in a wiper system using aDMM. Wire the windshield wiper circuit, verify a concern and answer the following questions as agroup.



WORKSTATION 4 WIPER SYSTEM DIAGNOSIS

5 - 14

BED148-A/VF

M

M

HOT IN ACCY OR RUN

2

6A

FUSEPANEL

63 RD63 RD

56 DB/OG

56 DB/OG 58 WH

58 WH

28 BK/PK

28 BK/PK 58 WH

WIPER SWITCH

B+ H L P W

WASHER SWITCHOFF HI

LO

OFF HI

LO


C201

C311

LH

CPARK RUN


S401

C237

941 BK/WH

941 BK/WH

941 BK/WH

57 BK

G402

WASHERPUMP

56 DB

63 RD

63 RD

28 BK

57 BK

G402

57 BK





3. What components or circuits could be the cause of the concern?

4. Diagnose the concern and use the spaces below to record what actions/tests you performed and theresult of each.

petStseT stluseR


A. High resistance

B. Open

C. Short to ground

D. Short to power

Disconnect all jumper wires and return the workstation to its original condition.

5 - 15



NOTES

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Basic Electrical Diagnosis - DealerConnection · Basic Electrical Diagnosis March, 2006 Units of...

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