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Your Partners for the Road Ahead!Your Partners for the Road Ahead!
Carman Scan VGCarman Scan VG
NEXTECHNEXTECH
andand
What is the advantage of a Combination DataScanner / Oscilloscope over a basic Data Scanner?
A basic Data Scanner can perform the following functions:
• Read and Erase Fault codes
• Display Current Data to verify a fault exists.
However, determining whether a fault is caused by a component failure, a wiring fault or a faulty ECM requires more than just a Scannermore than just a Scanner.
• Perform Actuation tests.
The Carman Scan 1 and Carman Scan VG provide the technician with a complete solution for Diagnostics.
The use of an Oscilloscope is a necessity forpinpointing vehicle faults.
During the course we will be studying the operation of the VG as well as the correct procedures required for testing a number of common components.
THE CARMAN SCAN VG THE CARMAN SCAN VG TRAINING COURSE TRAINING COURSE
#1#1
OSCILLOSCOPE TRAININGOSCILLOSCOPE TRAINING
THE OSCILLOSCOPE
VOLTAGE
TIME
0v
2v
4v
6v
8vHz % m/s
Hz = Frequency (Number of Pulses per second).
% = Duty Cycle (On/Off Ratio).
m/s = Time measurement.
The Lab Scope is one of the mostvaluable diagnostic tools availableto the modern workshop today.
It is commonly used to check:1. Supply voltage2. Voltage Drops (in power and earth circuits).3. AC Waveforms4. DC Waveforms (Square waves etc.)5. Pulse Signals
+ v
- v
0 v
TYPICAL AC WAVEFORM
AC Waveforms are generated from suchdevices as:Alternators (before rectification)Crank Angle SensorsTDC SensorsVehicle Speed SensorsTransmission Pulse Generators
0 v
5 v
ON
5 v
0 v
ON
OFF
OFF
GROUND SWITCHEDSIGNALDuty Cycle 50%
POSITIVELY SWITCHEDSIGNALDuty Cycle 50%
TYPICAL SQUARE WAVEFORM
Square Waveforms are commonly used for inputs such as:Crank Angle Sensors, Camshaft Sensors, TDC Sensors,Vehicle Speed Sensors, MAP Sensors (Ford),Air Flow Sensors or outputs such as Idle Speed Control Motors
TYPICAL PULSE WAVEFORM
SOLENOID PULSE SIGNAL
VOLTAGE SPIKE
12 v
0 v
Typical Solenoid Pulses include:Injectors; Canister Purge Solenoids etc.
SECONDARY IGNITION SECONDARY IGNITION OSCILLOSCOPEOSCILLOSCOPE
Typical Secondary Ignition PatternsTypical Secondary Ignition Patterns
Dwell
Ionization (Peak)Voltage
Burn Voltage
Burn Time
Decay Section
Secondary Ignition Specifications
Ionization (Peak)Voltage – 7-15 KV
Burn Voltage – 1-2 KV
Dwell – Depends on RPM
Burn Time – 1-2 m/s
Specifications – Idle, No load
Carman Scan VG Carman Scan VG
Oscilloscope OperationOscilloscope Operation
Selecting SecondarySelecting SecondaryIgnitionIgnition
Touch the “OSCILLOSCOPE” Icon.Touch the “OSCILLOSCOPE” Icon.
Selecting Secondary IgnitionSelecting Secondary Ignition
Touch the“Ignition Waveform” Icon.Touch the“Ignition Waveform” Icon.
Selecting Secondary IgnitionSelecting Secondary Ignition
Select the number of cylinders to be tested.Select the number of cylinders to be tested.
Selecting Secondary IgnitionSelecting Secondary Ignition
Select the type of Ignition and the approximate idle speed.Select the type of Ignition and the approximate idle speed.
Selecting Secondary Ignition typeSelecting Secondary Ignition type
Select the correct firing order from the list or make a Select the correct firing order from the list or make a new one using the numbers in “other”.new one using the numbers in “other”.
Selecting Secondary Ignition firing orderSelecting Secondary Ignition firing order
Select the correct probe. E.g. “1 to1” when using a single probe, Select the correct probe. E.g. “1 to1” when using a single probe, or “1 to 3” / “1 to 4” for Multi-Probes (DLI Ignition etc.)or “1 to 3” / “1 to 4” for Multi-Probes (DLI Ignition etc.)
Selecting Secondary Ignition Probe TypeSelecting Secondary Ignition Probe Type
Press “SAVE” when completedPress “SAVE” when completed
Special Note: DLI VehiclesSpecial Note: DLI Vehicles
Conventional Ignition vehicles are normally Conventional Ignition vehicles are normally “Negative”“Negative” firing, firing, and, therefore, the spark plugs fire from the centre electrode to the and, therefore, the spark plugs fire from the centre electrode to the outer electrode of the plug. outer electrode of the plug.
On DLI, Waste Spark vehicles, half of the cylinders are On DLI, Waste Spark vehicles, half of the cylinders are “Negative”“Negative”firing, and therefore fire from the centre electrode to the outer firing, and therefore fire from the centre electrode to the outer electrode of the spark plug, whilst the other half of the cylinderselectrode of the spark plug, whilst the other half of the cylinders(their mating cylinders)(their mating cylinders) are are “Positive”, “Positive”, firing from the firing from the outer electrode to the centre electrode. outer electrode to the centre electrode.
Please refer to the following diagram. Please refer to the following diagram.
Electron Flow
Distributor-less Ignition OperationDistributor-less Ignition Operation
When connecting the VG to a DLI Vehicle, the When connecting the VG to a DLI Vehicle, the “Positive”“Positive” cylinders cylindersare connected to are connected to Channel 1Channel 1 and the and the “Negative”“Negative” cylinders, connected cylinders, connected to to Channel 2.Channel 2. The The #1 Trigger#1 Trigger lead is connected to lead is connected to Channel 3 Channel 3 as usual.as usual.
When connecting the VG to a conventional Ignition Vehicle, the When connecting the VG to a conventional Ignition Vehicle, the Secondary Ignition pickup lead is connected to Secondary Ignition pickup lead is connected to Channel 2Channel 2 of the of the VG and the #1 Trigger lead is connected to VG and the #1 Trigger lead is connected to Channel 3Channel 3
Conventional Ignition Conventional Ignition
DLI Waste Spark Ignition DLI Waste Spark Ignition
Determining the Positive and Negative firing cylindersDetermining the Positive and Negative firing cylinders
If unsure which cylinders are If unsure which cylinders are PositivePositive firing and which are firing and which are NegativeNegative firing, simply take ONE secondary pickup lead and firing, simply take ONE secondary pickup lead andconnect it to Channel 1 or Channel 2 of the VG.connect it to Channel 1 or Channel 2 of the VG.
With the engine running, place the secondary pickup lead aroundWith the engine running, place the secondary pickup lead aroundone cylinder at a time. Any cylinders that produce an ignitionone cylinder at a time. Any cylinders that produce an ignitionpattern facing up the correct way on the scope are the correct pattern facing up the correct way on the scope are the correct Polarity for that channel.Polarity for that channel.
Please refer to the following diagrams. Please refer to the following diagrams.
Any cylinders displaying an upside down pattern are Any cylinders displaying an upside down pattern are incorrect incorrect polarity and therefore belong the the other Channel.polarity and therefore belong the the other Channel.
Correct Polarity for the channel selected.Correct Polarity for the channel selected.
Note, the Ignition pattern is displayed the correct way up.Note, the Ignition pattern is displayed the correct way up.
Correct Polarity.Correct Polarity.
Incorrect Polarity for the channel selected.Incorrect Polarity for the channel selected.
Note, the Ignition pattern is displayed upside down.Note, the Ignition pattern is displayed upside down.
Connect this Cylinder to the other channel.Connect this Cylinder to the other channel.Incorrect Polarity.Incorrect Polarity.
Demonstration here of determining correct PolarityDemonstration here of determining correct Polarity
SPLIT SCREENSPLIT SCREEN (Default Screen) = Parade + Single Cylinder (Default Screen) = Parade + Single Cylinder
NoteNote: This is a: This is a Waste Spark DISWaste Spark DIS vehicle. vehicle. Mating Cylinders are: 1&4; 3&6; 5&2.Mating Cylinders are: 1&4; 3&6; 5&2.
Screen SettingsScreen Settings
Sets the “Voltage Scale” for the Parade and Single Cylinder Patterns.
Sets the “Time Base” for the Parade Pattern only.
Sets the “Trigger Level”. Adjust whenever Patterns are erratic or Cylinder #’s are erratic or missing.
Allows the user to select which Single Cylinder will be displayed on the screen.
Allows the screen to be changed to display the patterns as either: “Series”(Parade), “Single Cylinder”, “Trend Plot” or “3D”.
Turns the “Information” display on or off.
Screen SettingsScreen Settings
Demonstration here of effects of incorrect Trigger levelDemonstration here of effects of incorrect Trigger level
Selecting a new “Single Cylinder” to be displayedSelecting a new “Single Cylinder” to be displayed
To Select a new single cylinder, pressTo Select a new single cylinder, press “CYLINDER”,“CYLINDER”, then press the cylinder #then press the cylinder #
To Select one of the other two cylinders, pressTo Select one of the other two cylinders, press “MORE”.“MORE”.
Selecting a new “Single Cylinder”Selecting a new “Single Cylinder”
#6 Selected
Selecting other Cylinders for display.Selecting other Cylinders for display.
Selecting a new “Single Cylinder”Selecting a new “Single Cylinder”
#3 Selected
Demonstration here of Selecting a New Single Cylinder for DisplayDemonstration here of Selecting a New Single Cylinder for Display
Changing Screen DisplaysChanging Screen Displays
Selecting new screen displaysSelecting new screen displays
To select new screen displays, TouchTo select new screen displays, Touch “SCREEN”“SCREEN”
““Series” (Parade) SelectedSeries” (Parade) Selected
Touching Touching “SERIES”“SERIES” displays the above Pattern displays the above Pattern
““Single Cylinder” SelectedSingle Cylinder” Selected
Touching Touching “CYLINDER”“CYLINDER” displays the above Pattern displays the above Pattern
Selecting a New Single CylinderSelecting a New Single Cylinder
To display a different cylinder, pressTo display a different cylinder, press
““Single Cylinder” SelectedSingle Cylinder” Selected
and then press “CYLINDER”.and then press “CYLINDER”.
Selecting a new Single CylinderSelecting a new Single Cylinder
After pressingAfter pressing “CYLINDER”, “CYLINDER”, press the “Cylinder #” required.press the “Cylinder #” required.
To select a new cylinder, Touch the cylinder # required.To select a new cylinder, Touch the cylinder # required.
Selecting a new Single CylinderSelecting a new Single Cylinder
Trend PlotsTrend Plots
““Trend” SelectedTrend” Selected
““Peak Voltage”Peak Voltage” for each cylinder is being displayed on the right for each cylinder is being displayed on the right
Cylinder #’s
PeakVoltage
““Trend” SelectedTrend” Selected
““Dwell Time”Dwell Time” for each cylinder is now being displayed on the right for each cylinder is now being displayed on the right
Dwell
““Trend” SelectedTrend” Selected
““Burn Voltage”Burn Voltage” for each cylinder is now being displayed on the right for each cylinder is now being displayed on the right
BurnVoltage
““Trend” SelectedTrend” Selected
““Burn Time”Burn Time” for each cylinder is now being displayed on the right for each cylinder is now being displayed on the right
BurnTime
3 Dimensional Raster Patterns 3 Dimensional Raster Patterns
““3D” (3 Dimensional) Raster or ladder Pattern Selected3D” (3 Dimensional) Raster or ladder Pattern Selected
Touching Touching “3D”“3D” displays the above Pattern displays the above Pattern
Demonstration here of Changing Screen DisplaysDemonstration here of Changing Screen Displays
Display for Open Circuit HT LeadDisplay for Open Circuit HT Lead
““Split Screen” with open circuit HT lead on # 5 CylinderSplit Screen” with open circuit HT lead on # 5 Cylinder
Note: High Burn KV shown above.Note: High Burn KV shown above.
High Burn KV.High Burn KV.
““Series Screen” with open circuit HT lead on # 5 CylinderSeries Screen” with open circuit HT lead on # 5 Cylinder
Also note faulty pattern on #2 Cylinder (DIS mating cylinder for #5)Also note faulty pattern on #2 Cylinder (DIS mating cylinder for #5)
High Peak KVHigh Peak KVHigh Burn KVHigh Burn KV
““Single Cylinder” with open circuit HT lead on # 5 CylinderSingle Cylinder” with open circuit HT lead on # 5 Cylinder
Note: High Peak Volts, High Burn Volts and Short Burn Time.Note: High Peak Volts, High Burn Volts and Short Burn Time.
““Trend Plot” with open circuit HT lead on # 5 CylinderTrend Plot” with open circuit HT lead on # 5 Cylinder
Note High Peak Voltage, High Burn Voltage and Low Burn TimeNote High Peak Voltage, High Burn Voltage and Low Burn Timeon cylinders 5 and 2on cylinders 5 and 2
High Peak KV
High Peak KV
High Peak KV
Short Burn Time
High Burn KV
““3D Screen” with open circuit HT lead on # 5 Cylinder3D Screen” with open circuit HT lead on # 5 Cylinder
Note High Peak KV, High Burn KV and Short Burn Time on Note High Peak KV, High Burn KV and Short Burn Time on Cylinders 5 and 2Cylinders 5 and 2
High Resistance in HT Lead(High Negative Slope, with normal peak KV)
Fouled Spark Plug or HT Leakage(High Negative Slope, with low peak KV)
Lean Cylinder under Acceleration(High Positive Slope, under load)
Other Faulty Ignition PatternsOther Faulty Ignition Patterns
Student Practical – Testing Secondary IgnitionStudent Practical – Testing Secondary Ignition
VG LABSCOPEVG LABSCOPE
Oscilloscope OperationOscilloscope Operation
For the remainder of the course, all waveforms will be displayed live on your VG. Please follow setup screens as shown on the following slides.
Touch the “OSCILLOSCOPE” Icon.Touch the “OSCILLOSCOPE” Icon.
Selecting Lab ScopeSelecting Lab Scope
Selecting Auto SetupSelecting Auto Setup
Touch the“Auto Setup” Icon.Touch the“Auto Setup” Icon.
Selecting Auto SetupSelecting Auto Setup
Select the type of signal to be tested and the channelSelect the type of signal to be tested and the channelto be used.to be used.
Selecting Auto SetupSelecting Auto Setup
After selecting the type of signal and the channel pressAfter selecting the type of signal and the channel press““SAVE” to progress to Lab Scope screen.SAVE” to progress to Lab Scope screen.
Press “SAVE” when completedPress “SAVE” when completed
20 m/s time-base is set for testing during “crank” conditions.If testing with the engine running reduce the time base.
Testing Crankshaft Position Sensors (Hall type) – Engine idlingTesting Crankshaft Position Sensors (Hall type) – Engine idling
To change the time-base, touch the side arrows or select “SET TIME”To change the time-base, touch the side arrows or select “SET TIME”
Testing Crankshaft Position Sensors (Hall type) – Engine idlingTesting Crankshaft Position Sensors (Hall type) – Engine idling
To change the voltage level, touch the up/down arrows or select “SET VOLT”To change the voltage level, touch the up/down arrows or select “SET VOLT”
Time-base adjusted to 2 m/s (per division) for testing with the engine running.
Testing Crankshaft Position Sensors (Hall type)Testing Crankshaft Position Sensors (Hall type)
Voltage scale set to 2v (per division)
Typical Crank Angle Sensor signal at idle.
Cylinder ID Signal.
Changing the Screen SettingsChanging the Screen Settings..
Changing the Screen settingsChanging the Screen settings: To change the screen settings touch “SCREEN” : To change the screen settings touch “SCREEN”
Changing the Screen SettingsChanging the Screen Settings..
Changing the Screen settingsChanging the Screen settings: “Waveform only” Screen selected: “Waveform only” Screen selected
Changing the Screen SettingsChanging the Screen Settings..
Changing the Screen settingsChanging the Screen settings: “Digital Display” Screen selected: “Digital Display” Screen selected
Digital readings displayedDigital readings displayed
Changing the Screen SettingsChanging the Screen Settings..
Changing the Screen settingsChanging the Screen settings: To change grid settings touch “GRID”: To change grid settings touch “GRID”
Changing the Screen SettingsChanging the Screen Settings..
To change the grid settings, select one of the above on the left.To change the grid settings, select one of the above on the left.
Changing the Screen SettingsChanging the Screen Settings..
To remove the grid (as seen above), touch To remove the grid (as seen above), touch
Changing the Screen SettingsChanging the Screen Settings..
To display quarter grid (as seen above), touchTo display quarter grid (as seen above), touch
Selecting a second channelSelecting a second channel
Selecting a second channel for testingSelecting a second channel for testing
After selecting the second channel press “SAVE” to After selecting the second channel press “SAVE” to progress to Lab Scope screen.progress to Lab Scope screen.
Press “SAVE” when completedPress “SAVE” when completed
Testing Crankshaft and Camshaft Position Sensors (Hall type)Testing Crankshaft and Camshaft Position Sensors (Hall type)
Crankshaft Position Sensor (CKP).
Camshaft Position Sensor (CMP).
5 m/s time base selected
Testing Crankshaft and Camshaft Position Sensors (Hall type)Testing Crankshaft and Camshaft Position Sensors (Hall type)
Crankshaft Position Sensor (CKP).
Camshaft Position Sensor (CMP).
Faulty Crank Angle Sensor SignalsFaulty Crank Angle Sensor Signals
Faulty Crank Angle Sensor Signal during crank.Faulty Crank Angle Sensor Signal during crank.
The vehicle here would not start as the hall sensor failed to switch the signal The vehicle here would not start as the hall sensor failed to switch the signal fully to ground (0v). Because of this, the ECM would not fire the Ignition.fully to ground (0v). Because of this, the ECM would not fire the Ignition.
Approx 1.0v
Ground = 0v
Problem was caused by a faulty Crank Angle Sensor
At first glance this pattern looks quite normal, however, if you study it closely you will see it’s definitely not normal.
Faulty Sensor signal captured on Carman Scan 1Faulty Sensor signal captured on Carman Scan 1
Duty cycle varying.
The uneven duty cycle resulted in dramatic ignition timing problems, causingThe uneven duty cycle resulted in dramatic ignition timing problems, causingbackfiring, misfiring and impossible driving conditions.backfiring, misfiring and impossible driving conditions.
Problem was caused by a “brand new” faulty Crank Angle Sensor.Problem was caused by a “brand new” faulty Crank Angle Sensor.
(Should have been a constant 50% duty cycleon this vehicle)
RecordingRecording
Please Note:Please Note:
2. To end the recording, Press 2. To end the recording, Press “STOP”.“STOP”.
3. If 3. If ‘STOP”‘STOP” is pressed before the full record time has elapsed, the is pressed before the full record time has elapsed, the VG will display a message to say it is VG will display a message to say it is “saving data, please wait”“saving data, please wait”
4. The 4. The lengthlength of the record time will depend on the time base of the record time will depend on the time base selected. selected.
1. The VG is always 1. The VG is always “recording”“recording” whilst in the Lab Scope mode. whilst in the Lab Scope mode.
Recording waveformsRecording waveforms
To stop waveform recording, press To stop waveform recording, press “STOP”“STOP”
Recording waveformsRecording waveforms
After pressing “STOP”, the above message will be displayedAfter pressing “STOP”, the above message will be displayed
Replaying the recorded waveform.Replaying the recorded waveform.
Replaying recorded waveformsReplaying recorded waveforms
To replay the waveforms, Press the left arrow.To replay the waveforms, Press the left arrow.
Progression indicator.
Recording waveformsRecording waveforms
To Pause the waveforms, Press the Pause.To Pause the waveforms, Press the Pause.
Waveform Paused.
Recording waveformsRecording waveforms
To To Save Save Recorded waveforms to the VG hard drive, Press “FILE”.Recorded waveforms to the VG hard drive, Press “FILE”.
Recording waveformsRecording waveforms
After pressing After pressing “SAVE”“SAVE” the above message will be displayed whilst saving. the above message will be displayed whilst saving.
Previously Previously “saved”“saved” recordings can be found by pressing recordings can be found by pressing “OPEN”.“OPEN”.
Zooming recorded waveformsZooming recorded waveforms
Previously recorded waveforms can be “Zoomed” in or out for better viewing Previously recorded waveforms can be “Zoomed” in or out for better viewing by pressing by pressing “ZOOM”.“ZOOM”.
Time base zoom Voltage zoom
Recording waveformsRecording waveforms
Waveforms can be zoomed, both in voltage and time, by touching the arrowsWaveforms can be zoomed, both in voltage and time, by touching the arrowsabove.above.
Recording waveformsRecording waveforms
Note here that the time base has been divided by 2, making the time base Note here that the time base has been divided by 2, making the time base 5 ms / div instead of 10 ms as it was when recorded. It may also be 5 ms / div instead of 10 ms as it was when recorded. It may also be multipliedmultiplied
Recording waveformsRecording waveforms
Note here that the voltage scale has been multiplied by 2, making the Note here that the voltage scale has been multiplied by 2, making the Voltage 1v / div instead of 2v as it was when recorded.Voltage 1v / div instead of 2v as it was when recorded.
Trigger SettingsTrigger Settings
Before discussing the various possible trigger settings available onBefore discussing the various possible trigger settings available onthe Carman Scan VG, the Carman Scan VG, it should be noted that in most cases the VGit should be noted that in most cases the VGuser doesn’t have to make any changes at all to trigger settings.user doesn’t have to make any changes at all to trigger settings.
This Powerful, user friendly Oscilloscope automatically sets This Powerful, user friendly Oscilloscope automatically sets all theall thebasic scope settingsbasic scope settings ready for testing by any user, whether highly ready for testing by any user, whether highly experienced or a total novice.experienced or a total novice.
Setting a Trigger point on an Oscilloscope, gives the scope a Setting a Trigger point on an Oscilloscope, gives the scope a reference point at which to start the pattern display on the screen. reference point at which to start the pattern display on the screen.
The trigger point can be set at The trigger point can be set at anyany position, and on position, and on any any channel channel of the scope.of the scope.
An example of using a trigger would be:An example of using a trigger would be: When displaying When displaying Secondary IgnitionSecondary Ignition patterns, the “trigger” pickup is patterns, the “trigger” pickup is attached to # 1 HT lead. attached to # 1 HT lead.
This means that the first cylinder to be displayed on the screen will This means that the first cylinder to be displayed on the screen will be # 1 (the trigger cylinder) followed by the remaining cylinders in be # 1 (the trigger cylinder) followed by the remaining cylinders in the firing order. the firing order.
If we removed the trigger pickup, the patterns may still be displayed, If we removed the trigger pickup, the patterns may still be displayed, however, there would be no way of identifying the correct cylinders on however, there would be no way of identifying the correct cylinders on the screen as the scope would have no reference point.the screen as the scope would have no reference point.
When using a Lab scope, setting a trigger point will keep the When using a Lab scope, setting a trigger point will keep the pattern steady on the screen. pattern steady on the screen.
If measuring signals on more than one channel at a time, the If measuring signals on more than one channel at a time, the trigger can be set on any channel.trigger can be set on any channel.
Triggered signals on one channel can be referenced against Triggered signals on one channel can be referenced against signals on other channels for exact timing etc. signals on other channels for exact timing etc.
E.G.1E.G.1 Using a Trigger pickup on # 1 HT lead, you can reference Using a Trigger pickup on # 1 HT lead, you can referenceexactly when # 1 spark plug or coil is being fired in relation to the exactly when # 1 spark plug or coil is being fired in relation to the Crankshaft Position Sensor (being measured on another channel).Crankshaft Position Sensor (being measured on another channel).
E.G.2E.G.2 When testing the timing of the When testing the timing of the Camshaft Position SensorCamshaft Position Sensor to tothe the Crankshaft Position SensorCrankshaft Position Sensor, triggering the two patterns together, triggering the two patterns togetherwill allow you to check the exact position of the sensors in relationwill allow you to check the exact position of the sensors in relationto each other, without physically removing any parts. to each other, without physically removing any parts.
Checking timing of CMP to CKP SensorsChecking timing of CMP to CKP Sensors
Crankshaft (CKP) and Camshaft (CMP) Sensors.
Checking correct timing of CMP Sensor
Trigger SettingsTrigger Settings (Note: a trigger gives the scope a reference point, allowing (Note: a trigger gives the scope a reference point, allowing the pattern to be repeated over and over again at the same position on the screen)the pattern to be repeated over and over again at the same position on the screen)
Making changes to the trigger settings can be done by either touching the Making changes to the trigger settings can be done by either touching the appropriate section on the screen or by touching “TRIGGER”appropriate section on the screen or by touching “TRIGGER”
Trigger on channel 1
Trigger SettingsTrigger Settings
To change trigger settings select one of the above.To change trigger settings select one of the above.
Trigger on channel 1
Trigger SettingsTrigger Settings: After touching “TRIGGER” the following selections can : After touching “TRIGGER” the following selections can be made.be made.
Changing the Trigger channelChanging the Trigger channel - Touch “CHANNEL” or touch the screen here. - Touch “CHANNEL” or touch the screen here.
Trigger now on channel 2
To move the trigger point to a new position, simply touch the screen in the upperTo move the trigger point to a new position, simply touch the screen in the upperleft section and drag the trigger point to a new position on the scope.left section and drag the trigger point to a new position on the scope.
Trigger PointTrigger Point
Trigger SettingsTrigger Settings: Moving the Trigger Point.: Moving the Trigger Point.
Drag this to wherever you want
Trigger SettingsTrigger Settings: Changing the Trigger Type: Changing the Trigger Type
Oscilloscope triggered on a “Rising” signal. Oscilloscope triggered on a “Rising” signal. To make the oscilloscope trigger onTo make the oscilloscope trigger on a falling signal, touch “TYPE” or touch the screen here.a falling signal, touch “TYPE” or touch the screen here.
Triggering on a rising signal
Trigger SettingsTrigger Settings: Changing the Trigger Type: Changing the Trigger Type
Oscilloscope now triggered on a falling signal.Oscilloscope now triggered on a falling signal.
Triggering on a falling signal
Trigger ModesTrigger Modes
The “mode” used to trigger the scope can be changed to suit theThe “mode” used to trigger the scope can be changed to suit theuser or the test being performed. user or the test being performed.
Trigger Modes available include:Trigger Modes available include:
1. 1. ““Auto” ModeAuto” Mode ( (Default mode)
In this mode the VG automatically displays the pattern, regardless of the
Trigger level selected.
2. 2. ““Normal” ModeNormal” Mode
In this mode the pattern will not be displayed until the “preset” trigger voltage
has been reached. If selected whilst patterns are currently being displayed, the patterns will be frozen on the screen until the correct trigger level has been set.
3. 3. ““Single” ModeSingle” Mode (Snap-shot mode) (Snap-shot mode)In this mode the VG automatically freezes the patterns on the screen as soon
as the correct trigger voltage has been reached.
Trigger SettingsTrigger Settings: Changing the Trigger Mode.: Changing the Trigger Mode.
To change the trigger mode from To change the trigger mode from ‘‘Auto’ to ‘Normal’, touch “MODE” or touch the screen here.Auto’ to ‘Normal’, touch “MODE” or touch the screen here.
Trigger SettingsTrigger Settings: Changing the Trigger Mode.: Changing the Trigger Mode.
Trigger mode changed from ‘Auto’ to ‘Normal’.Trigger mode changed from ‘Auto’ to ‘Normal’.Touch again to change from ‘Normal’ mode to ‘Single’ modeTouch again to change from ‘Normal’ mode to ‘Single’ mode
Trigger SettingsTrigger Settings: Changing the Trigger Mode.: Changing the Trigger Mode.
Trigger mode changed from ‘Normal’ to ‘Single’.Trigger mode changed from ‘Normal’ to ‘Single’.
Trigger SettingsTrigger Settings: Changing the Trigger Mode.: Changing the Trigger Mode.
When in ‘Single’ mode, the scope will capture a single screen shot only. When in ‘Single’ mode, the scope will capture a single screen shot only. To display a new screen shot touch “Run/Stop” To display a new screen shot touch “Run/Stop”
Testing Injector PatternsTesting Injector Patterns
To test an injector pattern, connect one of the lab scope leads to theTo test an injector pattern, connect one of the lab scope leads to theNegative terminal of the Injector to be tested.Negative terminal of the Injector to be tested.
Testing Injector PatternsTesting Injector Patterns
After selecting Inject… and the Channel #After selecting Inject… and the Channel #press “SAVE” to progress to Lab Scope screen.press “SAVE” to progress to Lab Scope screen.
Press “SAVE” when completedPress “SAVE” when completed
Testing Injector PatternsTesting Injector Patterns
Typical Injector Pattern at Idle. To check the exact injector duration use theTypical Injector Pattern at Idle. To check the exact injector duration use theCursors.Cursors.
Battery volts.
Zero volts.
Injector Off Spike ( Usually 70 – 100v).
Battery volts.
Injection Duration.
Testing Injector PatternsTesting Injector Patterns
To use the Cursers touch To use the Cursers touch “CURSER”“CURSER” once to bring up the first curser. Drag once to bring up the first curser. Drag the first curser to the start of injection. Touch “CURSER” again for the the first curser to the start of injection. Touch “CURSER” again for the second Curser. Drag the second cursor to the end of injection.second Curser. Drag the second cursor to the end of injection.
Curser.# 1
The Injection duration (3.36 m/s is displayed as “SET TIME” at the bottom The Injection duration (3.36 m/s is displayed as “SET TIME” at the bottom of the screen. The voltage difference is also displayed (13.25v) of the screen. The voltage difference is also displayed (13.25v)
Second Curser.
Testing Injector PatternsTesting Injector Patterns
Testing MAP and Throttle Position SensorsTesting MAP and Throttle Position Sensors
Engine drivability problems can often be caused by incorrect Engine drivability problems can often be caused by incorrect operation of MAP or Throttle Position Sensors.operation of MAP or Throttle Position Sensors.
The Oscilloscope is an excellent way of testing both of these The Oscilloscope is an excellent way of testing both of these sensors for correct operation.sensors for correct operation.
Testing Throttle Position Sensor and Map Sensor SignalsTesting Throttle Position Sensor and Map Sensor Signals
After selecting the second channel press “SAVE” to After selecting the second channel press “SAVE” to progress to Lab Scope screen.progress to Lab Scope screen.
Press “SAVE” when completedPress “SAVE” when completed
Testing Throttle Position Sensor and Map Sensor SignalsTesting Throttle Position Sensor and Map Sensor Signals
Throttle Position Sensor Signal
Map Sensor Signal
Check for smooth rise and fall in signals as accelerator is snapped open and Check for smooth rise and fall in signals as accelerator is snapped open and closed.closed.
Maximum Vacuum during deceleration
Full Throttle
Testing Throttle Position Sensor and Map Sensor SignalsTesting Throttle Position Sensor and Map Sensor Signals
Approx 0.35v
Approx 1.3v
Approx 4.3v
Approx 4.0v
Approx 0.7v
Typical Readings.Typical Readings.
Throttle Position Sensor Signal
Map Sensor Signal
Testing Idle Control MotorsTesting Idle Control Motors
Openingside
Closingside
Testing Idle Control MotorsTesting Idle Control Motors
With 3 wire type Idle Control Motors, the centre terminal is With 3 wire type Idle Control Motors, the centre terminal is usually supplied with battery volts, while the two outside wiresusually supplied with battery volts, while the two outside wiresare switched to ground by the ECM using a are switched to ground by the ECM using a variable duty cyclevariable duty cycle at a constant frequency.at a constant frequency.
One side is the One side is the opening sideopening side and the other is the and the other is the closing sideclosing side..The duty cycle on one side is inversely proportional to the duty The duty cycle on one side is inversely proportional to the duty cycle on the other side.cycle on the other side.
E.g. If the duty cycle on the opening side is 70%, the duty cycle onE.g. If the duty cycle on the opening side is 70%, the duty cycle onthe closing side will be 30% and visa versa.the closing side will be 30% and visa versa.
Opening Side = Approx 35%Opening Side = Approx 35%
Closing Side = Approx 65%Closing Side = Approx 65%
Testing ISC Duty Cycle Motor TypeTesting ISC Duty Cycle Motor Type
OffOff
OnOnOffOff
OnOn
Testing IAC Motor at hot idle with no load.Testing IAC Motor at hot idle with no load.
Opening Side = Approx 42%Opening Side = Approx 42%
Closing Side = Approx 58%Closing Side = Approx 58%
Testing ISC Duty Cycle Motor TypeTesting ISC Duty Cycle Motor Type
OffOff
OnOnOffOff
OnOn
Testing IAC Motor at hot idle with Air Conditioning on.Testing IAC Motor at hot idle with Air Conditioning on.
Testing Oxygen SensorsTesting Oxygen SensorsThere are two main types of oxygen sensors used on vehiclesThere are two main types of oxygen sensors used on vehiclestoday.today.
1. Zirconium (voltage generator type)1. Zirconium (voltage generator type)
2. Titanium (variable resistor type)2. Titanium (variable resistor type)
The following is a description of the testing procedure for a The following is a description of the testing procedure for a Zirconium Oxygen Sensor.Zirconium Oxygen Sensor.
As the Oxygen sensor is such an important part of the “Closed As the Oxygen sensor is such an important part of the “Closed Loop” feedback system, it is extremely important that you have Loop” feedback system, it is extremely important that you have a thorough understanding of the correct testing procedures.a thorough understanding of the correct testing procedures.
A faulty Oxygen Sensor not only has a detrimental affect on A faulty Oxygen Sensor not only has a detrimental affect on vehicle emissions and fuel economy, it can also cause dramaticvehicle emissions and fuel economy, it can also cause dramaticdrivability problems.drivability problems.
Testing Oxygen SensorsTesting Oxygen Sensors
Selecting Oxygen Sensor TestSelecting Oxygen Sensor Test
After selecting the type of oxygen sensor and the channel After selecting the type of oxygen sensor and the channel Press “SAVE” to progress to Lab Scope screen.Press “SAVE” to progress to Lab Scope screen.
Press “SAVE” when completedPress “SAVE” when completed
Good Oxygen Sensor Pattern at 2500 RPMGood Oxygen Sensor Pattern at 2500 RPM
1 Second
5 Crossovers
The “crossover” is the point where the 02 sensor signal crosses the midway (approx 500mv) point in the signal. The oxygen sensor’s speed is measured as the number of “Crossovers per Second”
Rich
Lean
Good Oxygen Sensor Pattern at IdleGood Oxygen Sensor Pattern at Idle
Note the slower speed of the 02 Sensor at idle.
1 Second
2 Crossovers
Bad Oxygen Sensor Pattern at 2500 RPMBad Oxygen Sensor Pattern at 2500 RPM
This may be caused by an over-rich air fuel mixture or a faulty (possibly contaminated) 02 sensor.
02 sensor voltage staying high (approx 800mv)
To test if the 02 sensor is causing the fault, disconnect an injector and check for a sharp drop in the signal. If the signal drops sharply the 02 sensor is OK and the high signal voltage is caused by an over rich air fuel ratio.
Bad Oxygen Sensor Pattern at 2500 RPMBad Oxygen Sensor Pattern at 2500 RPM
This indicates that the high voltage is caused by an over rich air fuel ratio, not a faulty 02 sensor
Sharp drop in 02 sensor voltage as injector is disconnected
Bad Oxygen Sensor Pattern at 2500 RPMBad Oxygen Sensor Pattern at 2500 RPM
02 sensor voltage staying low (0v)
This may be caused by a lean air fuel mixture, a faulty 02 sensor or grounded wiring.
To test if the 02 sensor is causing the fault, snap the throttle rapidly a few times or feed some LPG into the intake. If the 02 sensor voltage now increases the 02 sensor is OK and the low signal voltage is caused by a lean air fuel ratio.
Bad Oxygen Sensor Pattern at 2500 RPMBad Oxygen Sensor Pattern at 2500 RPM
Sharp increase in 02 sensor voltage as throttle is snappedopen a number of times.
This indicates that the low voltage is caused by a lean air fuel ratio, not a faulty 02 sensor or grounded wiring.
Current RampingCurrent Ramping
There’s no doubt about the value of a current probe for quick There’s no doubt about the value of a current probe for quick accurate diagnosis.accurate diagnosis.
More and more technicians are now starting to realise the valueMore and more technicians are now starting to realise the valueand are using a low current probe to test things like:and are using a low current probe to test things like:
• Fuel Pump operation/wearFuel Pump operation/wear
• Ignition coil operation/available currentIgnition coil operation/available current
• Coil on plug and DIS operationCoil on plug and DIS operation
• Injector operation/available currentInjector operation/available current
Testing Fuel Pump WaveformsTesting Fuel Pump Waveforms
To test a fuel pump waveform, connect the low current probeTo test a fuel pump waveform, connect the low current probearound a single wire going to the fuel pump.around a single wire going to the fuel pump.
(Using “Optional” Low Current probe).(Using “Optional” Low Current probe).
The electrical condition of a fuel pump can be assessed by viewingThe electrical condition of a fuel pump can be assessed by viewingthe current waveform for irregularities.the current waveform for irregularities.
Fuel Pump wear can be determined before complete failure occurs.Fuel Pump wear can be determined before complete failure occurs.
Good Fuel PumpGood Fuel Pump Faulty Fuel PumpFaulty Fuel Pump
Faulty Fuel PumpFaulty Fuel Pump
Typical Fuel Pump WaveformsTypical Fuel Pump Waveforms
Testing Fuel Pump condition using VGTesting Fuel Pump condition using VG
Normal waveform for good Fuel Pump.Normal waveform for good Fuel Pump.
Low current probe connected aroundfuel pump power supply wiring.
Testing DLI Ignition System using Low Current ProbeTesting DLI Ignition System using Low Current Probe
Normal waveforms.Normal waveforms.
#1 Trigger Pickup Signal
# 1/4 Coil
#1/4 Crank Angle Sensor Signal from 3 x sensor
# 1 & 4 Spark
Plugs firing here
Dwell starts
here # 3/6 Coil # 5/2 Coil
Current Probe around coil power supply wire
AC CouplingAC Coupling
Every signal we have tested up to this point has been with theEvery signal we have tested up to this point has been with theOscilloscope set to “DC” coupling.Oscilloscope set to “DC” coupling.
DC Coupling is the Default screen and is the best way to test mostDC Coupling is the Default screen and is the best way to test mostSensors and Actuators etc.Sensors and Actuators etc.
AC Coupling can be very valuable however for testing for “noise”AC Coupling can be very valuable however for testing for “noise”on power supplies, checking Alternator diodes etc. or for testing on power supplies, checking Alternator diodes etc. or for testing Knock Sensor signals.Knock Sensor signals.
Only Channel 1 can be AC CoupledOnly Channel 1 can be AC Coupled
Channel 1 connected to vehicle battery with DC Coupling selectedChannel 1 connected to vehicle battery with DC Coupling selected
To select AC Coupling touch “AC”.To select AC Coupling touch “AC”.
Approx 14 voltsApprox 14 volts
0 volts0 volts
Note: Only Channel 1 can be AC Coupled.Note: Only Channel 1 can be AC Coupled.
Note: Pattern is Note: Pattern is DC Coupled at DC Coupled at this timethis time
Channel 1 connected to vehicle battery with AC Coupling selectedChannel 1 connected to vehicle battery with AC Coupling selected
Approx 14 volts AC CoupledApprox 14 volts AC Coupled
Note: To check for any fluctuations in battery voltage Note: To check for any fluctuations in battery voltage change voltage scale tochange voltage scale toeither 50m/v or 100m/v per diveither 50m/v or 100m/v per div..
Pattern is now AC Coupled.Pattern is now AC Coupled.
Channel 1 connected to vehicle battery with AC Coupling selectedChannel 1 connected to vehicle battery with AC Coupling selected
Approx 14 volts AC CoupledApprox 14 volts AC Coupled
Note: To check condition of Diodes, load Alternator by operating accessories.Note: To check condition of Diodes, load Alternator by operating accessories.Maximum variation should be approximately 300m/v Maximum variation should be approximately 300m/v
Voltage scale set to 100mv/DivVoltage scale set to 100mv/Div
Analysing by Trouble TypeAnalysing by Trouble Type
Another very Powerful feature of the Carman VG is a featureAnother very Powerful feature of the Carman VG is a featurecalled “Analyse by Trouble Type”.called “Analyse by Trouble Type”.
With this feature, you can select from a list of possible faults orWith this feature, you can select from a list of possible faults orsymptoms and the VG will automatically select the componentssymptoms and the VG will automatically select the componentsto be tested for analysing the fault. to be tested for analysing the fault.
Each component will be allocated a channel for testing and theEach component will be allocated a channel for testing and theOscilloscope channels will be set up with appropriate voltageOscilloscope channels will be set up with appropriate voltageand time base settings. and time base settings.
Analysing by Trouble TypeAnalysing by Trouble Type
Touch the“Analyse by Trouble Type” Icon.Touch the“Analyse by Trouble Type” Icon.
Analysing by Trouble TypeAnalysing by Trouble Type
After selecting the type of fault, the components requiring testing will be After selecting the type of fault, the components requiring testing will be allocated their channels. Next select “SAVE” to progress to the Oscilloscope.allocated their channels. Next select “SAVE” to progress to the Oscilloscope.
Vehicle FaultVehicle Fault
Press “SAVE” when completedPress “SAVE” when completed
Analysing by Trouble TypeAnalysing by Trouble Type
Next select the type of sensors on the vehicle Next select the type of sensors on the vehicle (highlighted in bold)(highlighted in bold) and touch and touch “OK”“OK” to progress to the Oscilloscope. to progress to the Oscilloscope.
Analysing by Trouble TypeAnalysing by Trouble Type
Oscilloscope channels are now set ready for testing of components.Oscilloscope channels are now set ready for testing of components.
In ConclusionIn Conclusion
The knowledge gained by attending this course can only be ofThe knowledge gained by attending this course can only be ofbenefit if put into practice as soon as possible.benefit if put into practice as soon as possible.
Specialists are not created overnight.Specialists are not created overnight.
They are created by They are created by PRACTICEPRACTICE and the willing to learn. and the willing to learn.
Diagnostics is not magic, it perfected by applying Diagnostics is not magic, it perfected by applying BASICSBASICS..
A knowledge of how a system or component operates is one of theA knowledge of how a system or component operates is one of themost valuable tools when trying to diagnose a problem.most valuable tools when trying to diagnose a problem.
Study the operation of various components and you will find thatStudy the operation of various components and you will find thatit won’t matter what type of vehicle you are working on. They allit won’t matter what type of vehicle you are working on. They alloperate in a very similar manner.operate in a very similar manner.
Your Partners for the Road Ahead!Your Partners for the Road Ahead!
and Carman Scan VGand Carman Scan VG
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