SERVICE

ining CenterPrinted in German yCopyright by Dr-Ing . h . c . F. PorscheAktiengesellschaft

WKD 493 921

LIST OF CONTENTS

928 S 4

Test

Step

Description

Page

Precautions for Working on Electronic Ignition Systems 0 - 02

Testing Requirements - EZK and LH 0 - 03

Conditions Caused by Faults 2 - 0 1

Relay and Plug Connections on CEL 2 - 02

Plug Connections -- Control Unit LH 2 - 03

Plug Connections -- Control Unit EZK 2 - 04

Wiring Diagram for 928 S 4 Engine Electrical System 2 - 05

Fuel and Air Circuits 2 06

1.

Ground Points/Plug Connections - EZK and LH 2 -072.

Power Supply for EZK Control Unit 2 - 1 2

3.

Speed and Reference Mark Senders 2 - 1 4

4.

Temperature Sensor 11 - EZK 2 - 1 5

5.

Throttle Valve Switch for Idle Spped and Full Load - EZK 2 - 1 6

6.

Ignition (Ignition Timing, Ignition Pattern, Test Values) 2 - 1 7

7.

Hall Sender Signal 2 - 2 1

8.

Power Supply for LH Control Unit 2 - 229.

Power Supply for Fuel Pump I Speed Signal from EZK Control Uni tto LH Control Unit 2 - 25

10.

Air Flow Sensor Test 2 - 26

1 1 .

Temperature Sensor I I - LH 2 - 2812.

Throttle Valve Switch for Idle Speed and Full Load - LH 2 - 29

13.

Fuel Injectors and Injection Timing 2 - 3014.

Fuel Pressure 2 3215.

Leaks in Intake System 2 - 3416.

Idle Speed Control Test 2 - 3417.

Resonance Flap Function Test 2 - 3518.

Tank Vent Solenoid Valve Test 2 - 3719.

Speed Drop in Cars with Automatic Transmission 2 - 39

20.

Oxygen Sensor Control Test in Cars with Catalytic Converter 2 - 40

21.

Generator and Regulator 2 - 4 1Engine Adjusting/Testing Values 2 - 44Codes Depending on Country Equipment 2 - 45

1987

0-01

PRECAUTIONS WHEN WORKING ON ELECTRONIC IGNITION SYSTEMS

928 S 4

The requirements of modern engines on ignition systems and necessity for maintenance-free systemshad led to the introduction of electronic ignition systems in standard production some time ago .Normally the ignition power of electronic systems (almost all makes) will be higher than that ofconventional systems and even greater power can be seen in the near future .Consequently electronic ignition systems are corning into a power range, where even touching powersmarrying parts or terminals could be very dangerous (both primary and secondary sides) .

is in conjunction with this matter we must refer you to VDE regulations, especially VDE 01Q4/7 .61for Germany and/or regulations/legislation of a pertinent country when repairing or testing a n' nition system .

Always turn off the ignition (switch off ignition or source of power) when working on the ignitiasystem_ This work would include :

Connecting engine testers, .{ignition test lamps, dwell angle/speed testers, ignition oscilloscopes, etc . :

?li

Replacing parts of the ignition system(spark plugs, ignition coil, distributor, ignition leads, etc .)

e mentioned dangerous voltage will be in the entire system when it is necessary to turn on the-iition for ignition system tests or engine adjustments .

Consequently there is not only dangerous power in or on parts of the ignition system (for example :distributor, ignition coil, control unit, ignition tackle), but also on the wire harness (for example :tachometer connections, diagnosis plug connections), on plug connections and on testers .

, .,

I

TESTING REQUIREMENTS 928 S4

Important Car Instruction s

■ Only measure resist"':e after turning off the ignition or disconnecting the battery (tester coul dbe destroyed if not) .

• Pull off both control unit plugs when testing the compression pressure (otherwise there could b edangerous high tension, insulation damage on the ignition coil, high tension distributor an dignition leads) .

• Specified ignition coil (see Order Number) must never be replaced with a different ignition coil .

• A shielded capacitor must never be connected on ignition coil terminals 1 and 15 .

• Ignition coil terminal 1 must never be connected on ground for a burglar alarm system (ignitio ncoil and control units could be destroyed) .

• Battery positive (+) or any type of test lamp must never be connected on ignition coil terminal 1(control unit would be destroyed) .

• Never disconnect the ignition lead from ignition coil terminal 4 to high tension distributo rterminal 4 while operating the engine .

• There must never be voltage flashover from ignition coil terminal 4 to ignition coil terminals 1and 15 (control unit could be destroyed) .

s

Secondary end of the ignition must be shielded with at least 4 k-ohms to avoid destruction of th econtrol unit, whereby the original distributor rotor with a 1 k-ohm shielded resistor must b einstalled (do not use a 5 k-ohm distributor rotor even with radio or intercom shielding) .

• Only disconnect EZK control unit plugs with the ignition turned off .

• Flashover or disruptive discharge in the area of the high tension distributor cap (poor insulation )could destroy the control unit .

• Never disconnect the battery while the engine is running .

• Mixing up battery pole connections could destroy the control units, ignition coil or EZK contro lunit .

• Starting the engine with outside help of more than 16 V or a fast battery charger is forbidden .

1987

0-03

TESTING REQUIREMENTS - EZK/LH

928 S4

TEST

I

SUN Engine Tester 101 0

SUN Engine Tester Master 3

Bosch Engine Tester Mot 300/400

All sender and ignition timing signals of Porsch emodels can be tested with SUN 1010/1019 /Master 3 or Bosch Mot 300/400 engine tester srecommended by Porsche .Since instructions for connecting a tester on acar vary depending on the make of tester, youshould study the documents supplied with atester thoroughly before making connections .

Equi r

1 osc

1 dig

1 BoBo(C I

2 cot(mN 'pi e

1 ad ;4 Ftwi

1 tes

Test s

Mug '

Multi

LH a

Working with Oscilloscope

Sender Signals Which Can Be Tested: 1 - Reference mark sende r2 - Speed sende r3 - ti signals4 - Idle speed control activatio n5 - Hall sender signa l6 - Ignition triggering signal to final stage s7 - Speed pulse from EZK to LH control uni t8 - Activating signal for resonance fla p9 - Activating signal for tank ventalso :

10 - ti consumption signal (consumption display )11 - Ignition triggering signal from breakerless distributor s12 - Reed switch signal (speedometer )13 - ABS wheel sensor signal s

1987

0-04

1981

TESTING REQUIREMENTS - EZKILH

928 S 4

Equipment Required for LH and EZK Tests :

1 oscilloscope (for example SUN or Bosch )

1 digital displaying multimeter (for example Fluke 23 )

1 Bosch L-Jetronic test leadBosch No . 1684 463 093(Check leads for correct polarity in plugs . )

2 control unit plug test lead s(made locally) with 2 flat male plugs ,N 17 .457 .2, in order to avoid damagingplug pins on control unit plug during tests .

1 adapter test lead, consisting of :4 plug connectors N 017 .483 .1 withtwo approx. 150 mm long leads, soldered .

1 test lead 3-pin (for example VW VAG 1501 )

Test leads must always be used for tests !

Plug Terminal Designations :

Multiple-pin plugs of control units, looking at plug terminals !

LH and EZK

353433 32 31 30 29 28 27 26 25 24 23 22212019i t - r r

1817 16 151413121110 9 8 7 6 5 4 3 21

1987

0 -05

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X

X

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X

X

x

X

X

X

x

X

X

X

X

x

x

x

X

x

X

X

X

x

X

X

X

X

X

w

o'

'

Ground and plug connection s

Power supply for control uni t

Speed and reference mark sender s

Throttle valve switch - idle speed

Throttle valve switch - full load

Ignition system + final stages

Hall signal

n

7

X x x 05 Power supply for LH control uni t

x X X X X x x Power supply for fuel pump

X X Speed signal from EZK control uni t

x x X x x x x v Air flow senso r

X X X X X X X X Temperature sensor I I r7

x x x x X Throttle valve switch - idle speed mx

X

X

x

X

X X X X X x w

Throttle valve switch - full load

Fuel injectors - injection timingan

X x X X x x X x Fuel pressure

X x X X X X X X Leakage in intake syste m

X x X - Activation of idle speed contro l

x X X x y Activation of resonance fla p

x X x x X X X X oo Tank vent solenoid valve

x X X x Oxygen sensor in cat . cony . car s

X x Alternator 1 regulator

PS8Z6

Sflfl'd~ A8 a3Sf1V9 SNOIIIONOO

POWER SUPPLY FOR LH ! EZK CONTROL UNITS

928 S 4

P I

I

a~ aIV

VI

x

II

V

VI I

r- TL .L

I1~ft'~~'1~" 0

1

LH-Jetronic relay XXV, which in the past only had a burn-off function, is now additionall yresponsible for power supply to fuel injectors, idle speed control, tank venting valve, coding elemen tand switching valve for the resonance flap in contradiction to LH cars up to and including 198 6models, of which the fuel injectors, oxygen sensor and idle speed control were activated by fue lpump relay XX . This was necessary, in order to permit self-diagnosis in the future .

Power Supply For :

Fuel pum pOxygen senso r

LH control uni tEZK control uni t

Burn-off functio nFuel injector sIdle speed contro lTank venting valveCoding elementResonance flap switching valve

Central electric interfac ePower supply for EZK and LH control unit s

1 - Fuel pump relay X X

2 - EZK relay XV I

3 - LH-Jetronic relay XX V

4-Plug W

1987

2 -02

PLUG CONNECTIONS - LH CONTROL UNIT 2 .3

9285 4

Data cod e

LH-Jetronic relay XXV 8 5

Display (check )

CO poti (without CAT)Family curve corr . (with CAT)

Oxygen senso r

Load signal to EZK 9

Tank venting valve

Data cod e

Pump relay XX 85

+

'-f-T

M■`

Jr-

Speed from EZK 1 3

(N

Throttle valve switchIdle speedThrottle valve switchFull load

LC)

CO

C

Perm. pos. term. 30

Electronic ground MP I X

Ground from LH 2

Voltage from LH 3

H LM burn-of f

Voltage from XXV 87

Code for oxygen family curve

Automatic idle speed drop

Consumption output

fl!~ Diagnosis (K-Iead )from diagn. conn. 1 0

t NTC I I

AC compresso r

Idle speed contro l

Intake pipe resonance fla p

Power supply terminal 1 5EZK relay XVI 87

L)

Diagnosis (L-lead )

I

I n

Ground MP VII I

I

CD ~r

,,

Fuel injectors t i

I

I

I

C'"7(NI

N

LC)N

(0N(N

CDCN

I

1987

2 - 03

PLUG CONNECTIONS - EZK CONTROL UNIT

928 S 4

wIENG

I

8 1

. 7

88

89 1

90

Temperature sensor NTC I I

Knock sensor 1

Knock sensor 2

Hall sender 0

Speed sender +

Speed sender shield

Transmission protection switch

Throttle valve switchFull load

Coding input

Coding input

Power supplyTerm. 15 from XVI 8 7

Diagnosis plug term . 1 1

Ignition pulse tocontrol unit 1 (left )

Permanent positive 30

Diagnosis (K-lead )

ShieldingKnock sensor 1

ShieldingKnock sensor 2ShieldingHall sende r

Hall sender +

Speed sender -

Diagnosis inciting lead(L-lead )

Throttle valve switchIdle speed

Load signal from LH 25

Coding inpu t

Speed pulse toLH 1

Diagnosis plug 4

Ignition pulse tocontrol unit 2 (right )

Ground MP IX

t1987

2 - 04

Wiring Diagram Type 928S Model 87ENGINE COMPARTMENT TEMPOSTAT

A

B

I.

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85

86

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88

8 S

H M- N 0 P

AND AIR CIRCUITS

928 S 4

TE;

r)

Not

1 - Fuel pump2 - Fuel filter3 -- Fuel pipe4 - Distributor injection pipe s5 - Fuel injectors

A - Throttle valve housingB -- idle speed contro lC - Ejecto rD -- Pressure damperE - Pressure regulato rF - Vacuum valv eG - Electric tank venting valveH --- Oil filler neck1 - Blow-atf valv eK - Vacuum switching valv eL - Vacuum box

a - From fuel tan kb -- To fuel tan kc - From active carbon tankd - From vacuum reservoi re - To automatic transmission

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Grouabov

TEST STEP : GROUND POINTS 928 S4

Note : Test steps should be carried out in the given c.rr ;e !

-io 1 is especially important !

I'llake sure that you are testing with the correct tester, with correct tester settings and on correc t.,, .~<.point in conformance with specified requirements .

Symbols in Test Plan : V = voltmeter, Q = ohmmeter,= oscilloscope, < smaller (less) than ,7 = greater (more) than, °KW = crankshaft degree s

read the text precisely and without stress, in order to avoid wrong test results .

TEST STEP 1 : CHECKING GROUND AND PLUG CONNECTION S

Engine ground between engine an dbody on right-hand side underneathengine .

Ground of ignition control unit sabove right ignition coil .

1987

2 - 07

TEST STEP : GROUND POINTS AND PLUG CONNECTIONS

928 S 4

TES,

TEST STEP 1

Power ground underneath fuel pressur eregulator and fuel pressure damper .

TESL

Six-pconta

Shown here on removed engine for better recognition .Is the contact of connections good and tight?

Two-i

Plug Connection s

Fuel pump (1), EZK (2) and LH (3) relaysas well as plug W (4) on central electric .

.4

One each 35-pin plug on control unit sEZK (1) and LH (2) .

Plug connection for activation of ignitio nfinal stages (green/white lead) . Abovecentral electric .

1987

2 -08

B 54

TESTSTEPf PLUG CONNECTIONS

928 S 4

1 7

iition .

TEST.STEP 1

Six-pin plug on air flow sensor (only 5 plu gcontacts are used in the plug receptacle) .

Two-pin plug on temperature sensor I I .

Three-pin plug on speedlreference narkSender .

Two-pin plug on each of eight fuel injectors(first remove cover for ring pipes) .

- 48

1987

2-.D9

TEST STEP 1

Plug connections of knock sensors .

PlugFront sensor -- plug connection underneath

for tfUel ring pipe at left front .

--~

j 4

coveneat

S..

Rear sensor - plug connection above fuelring pipe at right rear .

Hall sender plug connection, Behind housin gfor camshaft drive gear - cylinder ban k1 -4 .

Plug connection of solenoid valve for reson-ance flap operation (at toothed belt cover ,cylinder bank 5 - 8) .

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mu

2 -D

1ST

TEST STEP : PLUG CONNECTIONS

928 S 4

TEST STEP 1

Plug connection of solenoid valvefor tank venting (at toothed bel tcover, cylinder bank 1 - 4, under-neath water hose) .

Plug connections of final stage s(on hood lock cross wall at left -hand side) .

121 7

Are these plugs connected correctly, not loose and not corroded ?Disconnect plugs ; plugs must not be bent on the pin or receptacle ends and also not corroded !

Since 928 S 4 cars are only fitted wit hone standard control unit (EZK as wel las LH) worldwide since 1987 modelsand these control units are coded t opertinent country equipment require-ments (see page 2 - 47 of Test Plan) ,this code must be checked in case o fcomplaint .

Coding element is located on back ofthe control unit carrier . Control unit smust be removed for checking .

1987

2-11

'ST VALUES - EZK

928 S 4

Ti- S

TEST STEP 2 : POWER SUPPLY FOR EZK CONTROL UNIT (V )

wer is supplied to EZK and LH control units of 928 S 4 cars via ignition lock terminal 15 as well asadditionally from battery + (permanent positive terminal 30) since 1987 model s

Permanent Positiv e

Connect voltmeter on terminal 18 e Ici terminal 35 q fcontrol unit plug . Display' bartte y voltage .

J .,itmeter on W 22 of connected CEL ploy?hody) .tt ry voltage .

Display :dge U 12 and W 22 on CEL plug with a test lead .

~nneet voltmeter on terminals 18 and 35 of contro lunit plu'splay : battery voitaw .

.

If the control unit plug has voltage in this test, the. r -dition is located within Central Electrics .

if the control unit plug does not have voltage, chec k,'..ring to CEL. plug U 12 according to the Wirin g

Diagram .

353433 3231 3029 28 27 26 25 24 23 2221201 9

11 a . - - J~ti 18 1716 15 14 13 12 11109 8 7 6 543 21r

2 5

1 r

23

Central Electric Plug W

Im p

1987

1!

TEST VALUES - EZK

928 S 4

b) Power Supply via EZK Relay (XVI )

Connect voltmeter on terminal 18 and terminal 29 of disconnected EZK control unit plug .

Turn on ignition . Display : battery voltage .

No Display :Connect voltmeter on W 14 of CEL plug and ground (body) . Turn on ignition .

Display : battery voltage .

If battery voltage is displayed, check power flow from CEL plug W 14 to terminal 29 o n

EZK control unit plug .

if there is no display, remove EZK relay (XVI) and bridge terminal 87 and 30 on relay socket .Now connect voltmeter on terminals 18 and 29 of control unit plug (however, ignitio nremains off for this test) . Display : battery voltage .

If battery voltage is displayed, check EZK relay and/or activation ,

No Display :Check voltage and ground supply on EZK relay socket to wiring diagram .

Important : Burglar alarm control unit or a plug bridge must be connected between B 23 an dF 25 of the CEL plug .

35 34 33 32 31 .si 79 28 27 26 25 24 2322 2120 19

%la17 16 15M13 12 I110 9 8 7 6 5 4 3 21

1987

2 - 13

TEST STEP 3 : SPEED AND REFERENCE MARK SENDERS (1 1 )

., test step can only be carried out with an os tConnect and adjust a workshop oscilloscope to insr< : urpplied with the tester for this purpos e(set display screen range to 20 V for Bosch MOT 3OL ..4 ;1 .

E sl .

Connect positive test lead via auxiliary lead on control unit terminE;i 23 and negative tester lead vi aauxilia ry lead on control unit terminal 6 (terminal 24 via auxiliary lead on ground") .

Crank engine with the star 1 :r motor . Sine oscillation of at least 3 V (speeA l.:'haher amplitude (reference mark) must be seen on the scr,Tr?

iA

Speedsignal

2 - Referencemark signa l

7c+7A

Sender distance cannot be adjusted . If there is insufficient or no deflection {C 3 V speed pulse )displayed on the screen, check connections or measure lead connections ; replace sender .

* Note : If there is a signal with tester connections an terminals 23 and 6 of the EZK contro lunit and terminal 24 is connected with ground during the test, the signal most h e

Slhle in the same form, If not, there is a short circuit in the sensor lead

TEST STEP 4 : TEMPERATURE SENSOR II I EZK SID EENGINE TEMPERATURE (Q )

Pull off EZK control unit plug .

Connect ohmmeter on terminal 19 and terminal 18 of EZK control unit plug;

Test values at

C = 4.4- 6 .8k S15--30°C= 1 .4- 3 .6k 4

40°C= 1 - 1 .3k Q80°C250-390 5

100° C = 160 - 210 Q

If

,e not reached, check sensor itself .In so doing don't connect ohmmeter o nboth contact lugs, but instead check eac hplug contact on temperature sensor agains tground (two independent temperatur esensors) .

1 --- EZK sid e2 - L H side

Note: Temperature sensor 11 advances the ignition timing of a cold engine for better enginepickup .

1987

2-15

TES

928 5

TEST STEP 5 : THROTTLE VALVE SV1ETCH (C?

a) Idle Speed Contact

all off LH control unit plug .innect ohmmeter on to , final

.find termir,

i EZ~ :r .

unit plug wi shelp of auxiliary lea n

With throttle valve closed

display : < 10 Qith throttle valve opened

display : 00 Q

idle speed contact must open (break) immediately (< 1 0 throttle valve 4)

ate : A breaking idle speed contact placer th

riition •,

in partial I

.- .L .rrve(advanced approx . 100

Break .

Mlle speed ignition timing approx . 200 - r ankshafcoasting shutoff, higher idle s r

cult :

. :sting shutoff while racing engine, one time •: :'

ch engine start .i tion timing retarded approx . 1 0n

b) Full Load

,nnect ohmmeter on terminal 26 ar -Id ten rii :im„ id O f dicortnected EZK control unit plug with;help of auxiliary leads . LH control unit plug must also be disconnected

ith throttle valve closed

display :;er approx . 213 throttle valve travel

display : < 10 Q

Note : A closing (making) full load contact retards the ignition timing into the full load famil ycurve l

Brie

} timing advanced appiux . 15

25`' in f ulull load enrichment .

ii 1 Circuit : Ignition timing retarded apfrc,x . 15 -- 250 in partial loan rang e

Check whether throttle valve moves ?c

:out entire ieretinci

e) Ad

ThreeLoosspeedIdle sFull I

Note:

TEST

Cents

At idlAt co

EZKthe "+canntI t l

Ifs *the 1gFirir>n

19B7

-16

c) Adjusting Throttle Valve Switch

Throttle valve in idle speed position .Loosen screws of throttle valve switch and turn throttle valve switch far enough, until the idl espeed contact switches .Idle speed contact must switch while opening the throttle valve after a gap of approx . 1 0 .Full load contact is adjusted automatically with the idle speed contac t

Note: Intake branch must be disassembled to adjust a throttle valve switch .

TEST STEP 6 : IGNITIONS\.c_

14 1 V )

Controlling Ignition Timing

At idle speed of

675 ±25 rpm

10 ± 2° before TD CAt control value of

3000 rpm

32 ±40 before TDC

EZK control unit does not have a vacuum connection (load sensor), but instead now receive sthe "engine load" information as an electronic signal from the LH control unit . This signa lcannot be checked with common workshop equipment .If this load signal is missing on an EZK control unit, ignition timing will be retarded up to 25 0on crankshaft in partial and full load ranges (full load family curve, as protective circuit) !

if a secondary display appears on the oscilloscope, engine tester must be set to 4 cylinders sinc rthe ignition system is divided into two separate ignition circuits .Firing order : 1--3-7-2-6-5-4-8.

ignition Circuit I :High tension distributor on exhaust camshaft, cylinders 1 - 4 :

1-7-6---4

ignition Circuit II :High tension distributor on exhaust camshaft, cylinders 5 - 8 :

5--8--3-2

1987

17

928 S 4

An ignition coil installed at right front as seen looking forward in car is responsible for high tensio nwer supply of ignition circuit 1, while the ignition coil installed at left front is responsible for hi- L -orin pnwr'- :apply of ignition circuit ll .

a) Connection of Engine Test :: :

Connect engine tester to instructions supplied with tester and adjust (note 4 cylinder test range) .

It ignition ;.,_;rtern of ignition circuit I (right-hand side) is visible, connect tester on cylinde rignition le, 2nd right front ignition coil

PrI nSec (Vo l

Hig lDis tV istJs Vs

Spa 'Shi E:~is~

Cylin

7

6

If ignition pattern of ignition circuit I I (left-hand side) is visible, connect tester on cylinder 5.gnition lend, :,nri [eft front ignition coil .

o

3

2

5Cylinders .

5 8

Note: If a fault is displayed for all cylinders, it is in the primary or secondary circuit betw e -the ignition coil and distributor rotor .

a fault is displayed for only one cylinder, it is after the distributor roto r

1937

TEST VALUES - EZK

928 S 4

b) Resistance on Ignition Coil, High Tension Distributor and Spark Plug Connectors

Ignition Coil (S2 1 V) :Primary resistance

Terminals 1 + 15

0 .4 - 0.7 C?Secondary resistance Terminals 1 + 4

5 .0 - 8.7 k gVoltage on terminal 15 with engine running

> 10 V

High Tension Distributor (C ) :Distributor finger shielded resistanceVisual inspection for damage and traces of burnin gas well as cracks in cover .

Spark Plug Connectors (52) :Shielded resistanceVisual inspection for damage, traces of burning an doxidation .

c) Activation of High Tension Sid e

ignition triggering signal can be simulated for fast ignition end troubleshooting .This is accomplished by disconnecting a two-pin plug (arrow) above CEL (green/white lead) .Connect plug pins with an auxiliary lead .

Connect oscilloscope tester lead terminal 4 on ignition lead terminal 4 .

1 kg

3 kg

1887

2-19

TEST VALUES - EZK

928 S 4

TE5

Turn on ignition . Now if positive is applied on one of both plug pins in intervals with help of tieauxiliary lead, a high tension needle (ignition triggering) must appear on the oscilloscope eachtime.

If no signals appear, check

power supply of final stage and ignition coil ,ground point for final stages (underneath right ignition coil) ,

- plug connections on final stages, ignition coils and high tension distributor ,-- components (e .g . ignition coils, ignition leads, spark plug connectors, etc .) responsible for high

tension and-- power flow in leads from control unit plug to final stage (green lead for ignition circuit I and

white lead for ignition circuit I1) .

,d

g't ontrol Signal for Final Stage (I)

Carry Out test on both disconnected fina lplugs .

, Connect positive tester lead on terminal 5and negative tester lead on terminal 2 ofdisconnected final stage plug .Operate starter motor .Oscilloscope should display a contro lSjgnal on each final stage plug.

1987

2 -20

TEST VALUES -- EZK

928 S 4

Important Note : Baseplate must be coated with a heat conducting paste prior to installation o ffinal stages . Never apply heat conducting paste on painted parts .Heat conducting paste : Bosch No . 5 942 860 003 .

- Final stag e

Baseplat e

TEST STEP 7 : HALL SENDER SIGNAL (+ )

Disconnect plug on cylinder head 1 - 4behind camshaft drive gear and connec ta 3-pin adapter lead IVW 1501) betwee nplug and cylinder head to test the hal lsignal .Connect positive and negative tester lead son terminals 1 and 2 of adapter lead, con-nect tester to instructions supplied wit htester and start engine .

Following signal will appear on screen, i fhall sender system is okay .

If hall signal or one of knock sensor sig-nals is missing, ignition timing will be re .tarded by about 60 for all cylinders i nupper partial load and full load range sby the control unit (protective circuit),

V Vie'- 15 0 1

Voltage signal approx. 5 V

1987

2 . 21

TEST

.!ES - LH-JE';- ; :. . :

928

SST STEP 8 E-,

P. SUPPLY FOR LH CONTROL UNIT (V)

a) Permanent Positiv e

"Connect voltmeter on terminal 17 and terminal 4 of LH control unit plug with help of auxiliary lead .Display : battery voltage .

liNo Display :Connect voltmeter on CEL plug W 22 and ground with help of auxiliary lean.'Display : battery voltage .

If battery voltage is displayed, check power flow in lead from CEL plug W 22 to control unit plu gterminal 4 ,

No Display :,C_onnect U 12 and W 22 of CEL plug with help of auxiliary lead . Connect voltmeter on terminal 1 7And terminal 4 of LH control unit plug with help of auxiliary lead .Display : battery voltage.

!Battery voltage displayed = condition within CEL .No display = check power supply to wiring diagram.

35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19

----------------- -

18 17 16 15 14 13 12 11 10 9 8 7 5 4 3 21

At

4

an (

1987

2 - 22

i28S4

TEST VALUES - LH-JETRONICC

b) Power Supply Via LH Relay XX V

Connect voltmeter on terminal 17 and terminal 9 of LH control unit plug with help of auxiliary lea dand apply on ground terminal 21 (body) with help of auxiliary lead . LH relay must be activated .Display : battery voltage .

No Display :Connect voltmeter between connected CEL plug W 23 and ground and then connect between termina l17 and terminal 21 of LH control unit plug with help of auxiliary lead (ground signal to LH relay) .Display : battery voltage .

If battery voltage is displayed, check lead connection between CE L plug W 23 and LH control uni tplug terminal 9 .

No Display :Remove LH relay (XXV) and bridge terminals 87 and 30 on relay socket . Connect with voltmeter o rLH control unit plug terminals 17 and 9 with help of auxiliary lead .Display : battery voltage.

Battery voltage displayed = check LH relay and its activation .No voltage displayed = check lead connections to wiring diagram.

353433 323130 29 28 37 26 252423 2221 201 9

,I ----------------- -

18 17 16 15 14 13 12 1110 9 8 7 6 5 4 3 21J

y lead,

1987

2 - 23

.

TEST VALUES LH-JETRONIC 9288 4

~

.

~

mjPower Supply VimFZK Relay XV I

Connect voltmeter on terminal 5 and terminal 35 of LHomntno! unit plug . Turn on ign!tk*n.-Dimolay : battery voltage .

No Display :Connect voltmeter on connected CE Lplug VV 14 and ground . Ignition on .Display : battery voltage .

If battery voltage is displayed, check lead connection between CEL p!uQVV 14 and LH contnnl unit

plug terminal 35 .

No Display :Remove EZK relay and bridge terminal 87 and terminal 30 on relay socket . Connect voltmeter onterminal 35 and ternn(na! 5 of LH control unit plug .Display : battery voltage .

Battery voltage displayed = check EZK relay and its activation .No voltage displayed - check lead connect ions to wiring diagram .

~~~

18 17 16 15 14 13 12 11 109 8 7 6 543 2

+

°+

~

~^

~ '

- .` ".~ . .,

-

,

. .

.

_=

^

- ,1987

2 '24

35 34 33 32 31 30 19 28 27 26 25 24 23 2221 20 19-

TEI

-

',`+LUES - LH-JE

! .iNIC

928 S 4

STEP 9 : POWER SUPPLY FOR FUEL PUMP (V )

Fuel pump ieiay XX is activated with ground from LH control unit .Check ac,avation of fuel pump by bridging terminal 20 and terminal 17 on LH control unit plug wit hhelp of an auxiliary lead . Turn on ignition . Fuel pump runs .

.,r n ;) Does Not Run :k fuse no . 42 . If fuse is okay, remove fuel pump relay and bridge terminal 87 and terminal 30 o n

d•i socket . Fuel pump must run .

if pump runs, check relay and its activation .If pump does not run, check leads and connections for fuel pump and/or fuel pump itself .

■

rib 353433 323130 29 28 27 26 252423 2221201 9

: :----:::- - - -1--l i 18 17 16 15 14 1312IT 109B7 6 5 4 3 21r

Speed Signal from EZK Control Unit to LH Control Unit fl)

Important : EZK control unit plug connected, LH control unit plug disconnected .

Connect terminal 17 and terminal 1 of LH control unit plug with engine tester leads with help o fauxiliary leads .

2-25

Set oscilloscope to instructions supplied wit htester, start engine with starter motor .Control signal must appear on oscilloscope .

TEST VALUES -- LH-JETRONIC

928 S 4

If no signal appears, check power flow from LH control unit plug terminal 1 to EZK :MUM Unitplug terminal 13. If there is power flow, replace EZK control unit .

35 34 33 323130 29 28 27 26 252423 2221201 9

1817 16 15 1413 121110 9 8 7 6 5 4 3 21

TEST STEP 10 : LH AIR FLOW SENSOR (Vlsrl)

:a) Power Supply (V)

Pull off plug on air flow sensor. Connect voltmeter on plug terminals 2 and 4 with help o fauxiliary leads .

Connect terminal 17 and terminal 21 of disconnected LH control unit plug with help of auxiliar ylead .Display : battery voltage .

No Display :Remove LH relay XXV and bridge terminal 87 and terminal 30 on relay socket . Display ofvoltmeter connected on air flow sensor plug : battery voltage .

Battery voltage displayed = check LH relay and its activation .No voltage displayed = check lead and plug connections to wiring diagram .

11 8 S 4

TEST VALUES - LH-JETRCNIC

928 S 4

6) Resistance Test of Hot Wire Circuit on Air Flow Sensor (Q )

Disconnect plug on air flow sensor_ Connect ohmmeter on terminals 3 and 5 of air flow sensor .Display : 3 .6 - 4 .1 0

c) {decking Hot Wire Signal (V )

Connect plug on air flow sensor . Remove LH relay XXV and bridge terminal 87 and terminal 3 0on relay socket . Connect voltmeter on terminal 6 and terminal 7 of LH control unit plug .Display : = 1 .6 V

Blow air on hot wire in air flow sensor and observe the voltmeter . There should be a change in voltage(-1 .6 -5 VI .

35 34 33 323130 29 26 27 26 25 24 23 2221 20 19

18 171b 15 14 1312 11 109 S 7a5 4 3 21

+ +

d) Checking Burn-off of Hot Wire Circuit (Visual Check )

Run engine with installed and connected air flow sensor .increase engine speed to more than 2000 rpm after engine has reached a temperature of 7 60 0 Cand then stop the engine (ignition off) . Hot wire must glow (burn-off function) approx . 1 secondafter waiting approximately 4 seconds .

e) Emergency Running Program (s)

An emergency running program is stored in a memory of the LH control unit and is activated, i fthe air flow sensor fails . The car can then be driven to the nearest authorized workshop .

Warm engine and speed < 2000 rpm - 3 .5 ms t iWarm engine and speed > 2000 rprn - 6 .3 ms ti

(ti = injection time )

1987

2 . 27

TEST VALUES- .LH~I tR 11i.IC

928 S 4

TEST STEP 11 : TEMPERATURE SENSOR I I - LH .

Disconnect LH control unit plug .Connect ohmmeter on terminal 13 and terminal 5 or 17 of LH control unit plug with help o fauxiliary leads.

353433 32 3i3029 28 27 2!► 25 24 23 22 21 20 19

18 177615 14 13 12 11 109 8 7 6 5 4 3 21

4

+

+

Display: Resistance

Test value at

0° C = 4.4 - 6.8 k g15- 30°C= 1 .4- 3.6k Q

40°C= 1 .0-- 1 .3 k0800 C=250-290 0

1000 C = 100-210 0

If values are not reached, test direct on sensor . in so doing do not connect ohmmeter on bothcontact lugs, but instead check each contact lug against ground separately (two independenttemperature sensors) .

Note : Temperature sensor I I sends information on engine temperature to the control unit .It causes an enrichment of the fuel/air mixture for cold starts and warming up .

TEST VALUES - LH-JETRONIC

928 S4

Break

S2) :

Excessively rich mixture .Engine in warm state stalls and cannot be started again .Emergency running can be reached with bridging (0 Qi in case of a brea k

0 )

Short Circuit (0 0f :

No engine pick-up in cold state, mixture too lean, stalls .No effect at operating temperature .

TEST STEP 12 : THROTTLE VALVE SWITCH (Q )

o) Idle Speed Contact

Disconnect plug on EZK control unit .Connect ohmmeter on terminal 17 and terminal 2 of LH control unit plug with auxiliary leads .Display: throttle valve closed

< 10 Qthrottle valve opened> I°

o0 4

Idle speed contact activates coasting shutoff .

Break

= no coasting shutof fShort circuit = coasting shutoff one time while racing engine after each engine start .

35 34 33 32 31 30 29 28 27 26 23 24 23 23 21 20 14

L "1817 16 15 14 13 12 11 109 8 7 6 5 4 3 21

TEST VALUES - LH-JETRONIC

928 S 4

II

I

b) Full Load Contac t

Connect ohmmeter on terminal 17 and terminal 3 of control unit plug with auxiliary leads . Alsodisconnect plug on EZK control unit .Display : Throttle valve closed

QThrottle valve opened approx . 2/3 of distance < 10 Q

Full load contact activates full load enrichment .

Break

= too lean with full load, power output insufficient .Short circuit = enrichment too early, high fuel consumption .

f 35 34 33 323130 24 28 27 26 25 24 23 2221 20 19

18 17 16 15 14 1312 11109

7 6 543 21r1

See Test Step 5 c for switch adjusting procedures .

TEST STEP 13 : FUEL INJECTORS - INJECTION TIMING (V/Q/ )

a) Fuel Injector s

If it is possible to run the engine, pull off injector plugs seperately . Engine speed will drop in case o fgood fuel injectors or perfect combustion .Proceed as described below when engine cannot be run .

Pull off injector plugs (after first removing cover on the ring pipe) . Remove LH relay XXV and bridg eterminal 87 and terminal 30 on relay socket . Connect voltmeter on injector plug contacts and groundwith help of auxiliary leads .Display : battery voltage .

Check leads and connections to wiring diagram, if there is no display .

Check coil resistance on connecting contacts of fuel injectors with an ohmmeter .Test value:- 16 S?

928 S 4

TEST VALUES - LH-JETRONIC

928 S 4

b) injection Final Stage

Adjust oscilloscope to instructions suppliedwith tester . Connect Bosch test lead(1 684 463 093) between on fuel injecto rand plug . Connect tester leads on test lead sto instructions supplied with tester .

Cautionl Tester leads must not hav econtact with ground .

; ;icrt engine . Following pictures must be displayed when injection final stage is working correctl yand test connections have been made correctly .

tjrot-

Starter speed

Idle speed

Note :

If engine does not star tor idle speed drops ,change tester connection son test leads and chec ktester adjustments .

ti re-

1987 2-31

TEST VALUES - LH-JETRONIC

92854

Accelerating

DeceleratingIf "ti" is not stoppe dwhile decelerating, se eTest Step 12 a l

TEST STEP 14: FUEL PRESSURE.

A test connection is located on the fue lring pipe at right front . Unscrew cappednut on test connection .

I portant : Inserted sealing ball couldfall out .Connect pressure teste rP 378 on adapter .

1987

2-32

928

JETRONIC

928 S 4

Start engine, at idle speed with vacuum on pressure regulator :Test pressure : 3 .3 ± 0.2 bar .

Test on stopped engine and running fuel pump without vacuum on pressure regulator (for thispurpose fuel pump relay XX is removed and terminals 87 and 30 bridged) :Test pressure : 3 .8 ± 0 .2 bar .

Slowly pinch return hose of pressure regulator with a hose clamp (e .g . at fuel level transmitter) :Fuel pressure with running pump less than 4 .5 bar = check fuel filter, replace fuel pump .

Hot Starting Problem s

Fuel pressure of a warm engine may drop by maximum 0 .5 bar in 30 minutes (pressure holdin gtest) .

Causes for Hot Starting Problem s

Parts :

Pressure regulator leaking

Electric fuel pump check valve fault y

Fuel injectors leaking

Radiator fan running on

Test :

Pinching return hose

Pinching pressure hose

Pinching both hoses

See pages 9 - 09 and 9 - 10 in 198 7Model Info-m:ition ff,! fr

19 ;

2

TEST VALUES - LH-JETRONIC

92854

TEST

TEST STEP 16 : ACTIVATION OF IDLE SPEED CONTRO L

Bridge terry anal l 7 and terminal 21 on control unit plug with help of auxiliary lead . Apply ground(n terminal 33 of control unit plug in intervals with help of auxiliary lead .Fuming of idle speed control will be heard up to the stop .

T T35 34 33 32 31 30 24 28 27 76 25 24 23 22 21 20 1 9

- ----------------

18 17 16 15 14 13 12 fl 109 8 76 5 4 3 2 1r4

Peck tightness of all conneclions after air flow sensor andfor leaks .

Mount locally made too onair flow sensor with 4 x 45screws and build up 0 .3 barpressure. Pressure will drop in.intake system or escaping ai rwill be heard in case of leaks .

TES's

rew0>3

11

TEST VALUES - LH-JETRONI C

ks .

is

92BS 4

A resonance valve in the intake system will be opened by vacuum in certain speed ranges and witheast 1/3rd engine load . This is also applicable to each start (requirement : vacuum in supplyk) .

a) Checking Flap Functio n

Remove cover (rubber cap) of theresonance valve shaft above the intak eWeb . q raw a center line on the surfac eof the valve shaft with a soft-tip pen o rsomething similar (makes it easier U1recognize opening movement) .

Start engine : valve opens and closesduring starting procedures .

Accelerate abruptly to wide openthrottle after engine is running : valveopens and closes ,(Conditions : speed greater than 3500rpm and at least 1/3rd engine load )

b)Checking Resonance Flap Functio nwithout Running Engine :Vacuum End

Pull off vacuum feed hose from suppl ytank on solenoid valve . Check vacuu mwith a vacuum tester :-0 .6 bar

A - From vacuum tan kB - To resonance flap

TEST STEP 17 : ACTIVATION AND FUNCTION OF RESONANCE FLA P

1987 2 - 35

3

TES1

Now supply approx . 0 .4 bar vacuum in the hose leading to the diaphragm valve (below intake web )with a vacuum pump = resonance flap opens .

Flap Does Not Operdiaphragm valve

( layout drawing (page 2 - 06) .

c) Power Supply (V I

Bridge terminal 17 aria terminal 21 on LH Control

nelp of an auxiliary lead . Applyground on terminal 34 of control unit plug with ano[', , •uxil i y lead = resonance flap open s

Flap Does Not Open :Connect terminal 17 and terminal 21 on LH control unit plug . Disconnect plus : in solenoid va iConnect voltmeter on plug recept-3w 1 ?1 and ground .Display : battery voltage .

No Display :Check power supply T : ,

valve via LH relay XXV t- n wringauram and test power i low fro m

i'rnilrol unit r,

a al 34 to_ction

1

2

(l) Checking Control Signal with Oscilloscope (E .

Connect LH control unit plug . Disconnect plug an solenoid valve- Connect engine tester o nreceptacle end of solenoid valve plug to instructions supplied with tester with help of auxiliar yleads and adjust the tester (with Bosch MOT 300/400, however select screen test range 20 V) .Following picture must be displayed on tester while starting engine as well as with running engine`and abrupt opening of the throttle valve .

TEST VALUES -- LH,JETRONIC

928 S 4

Ii

r

TEST STEP 18 : SOLENOID VALVE FOR TANK VENT

LH control unit activates and opens the solenoid valve with a timed ground signal when engine ha soperating temperature and the throttle valve (idle speed contact) is open . Opening time of solenoi dvalve is longer as the air flow rate in the air flow sensor increases .

a) Checking Activatio n

Connect terminal 17 and terminal 21 on LH control unit plug with auxiliary leads . Apply ground(body) to terminal 27 with an additional lead : solenoid valve opens .

Valve Does Not Open :Check power supply and power flow from LH control unit terminal 27 to solenoid valve to th ewiring diagram .

b) Checking Power Supply IV )

Connect terminal 17 and terminal 21 on control unit plug with auxiliary leads. Connect voltmete ron plug connector and ground of disconnected solenoid valve plug with auxiliary leads .Display : battery voltage .

No Display :Check power supply via LH relay to wiring diagram .

I353433 323138 29 28 27 26 252423 2221 20 1 9

-------------------------

~18 17 6151413 12 11109 8 76 5 4 3 21r

TEST VALUES - LH-JETRONIC

928 S 4

c) Checking Control Signal with Oscillos

'(

Connect q ME test lead (Bosch No .1 684 463 093) between solenoi dvalve and plug connection. Connectand adjust engine tester to instruc-tions supplied with tester (withBosch MOT 300/400, howeverselect screen test range 20 V) .Start engine and accelerate lightly`idle speed contact must open,engine temperature > 600 C)-,Following picture is displayed.;

Signal is wideras air flow rateincreases!

Tank vent

1987

2 -38

TEST VALUES -- LH-JETAONIC 928 S4

TEST STEP 19 : CHECKING ACTIVATION OF SPEED DROP FOR ENGAGING DRIVE RANG EI .N CARS WITH AUTOMATIC TRANSMISSION (Q)

a )Connect ohmmeter between terminal 17 and terminal 30 of disconnected LH control unit plug withhelp of auxiliary leads .

.t 353433 373130 29 28 27 26 25 24 23 22212019:

18 17 16 1514 13 12 11 109 876 5 4 3 21

4

Selector lever in P or N :

Display : < 10 0Selector lever in R or q or 3 or 2 :

Display :cc 0

If these display values are not reached, check wiring via plug V 14 and U 23 to starter switch o ntransmission to the wiring diagram .

IA Checking with Engine Runnin g

Connect control unit plug, Start engine and operate brake pedal . Selector lever in R or D .Idle speed must now drop by approximately 30 to 50 rpm .

Caution : danger of accident because of rolling car!

TEST VALUES - LH-JETRONIG

928 S 4

•f ITEST STEP 20: CHECKING OXYGEN SENSOR IN CARS WITH CATALYTIC CONVERTER (V)

Simple checking of control can be carried out in spite of adaptive oxygen sensor control .

a) Checking Sensor Signal (V)

Disconnect oxygen sensor plugclose to central electric . Con-nect voltmeter with each plugpin on sensor end and ground .

Test connection

Display on voltmeter : 0.1 - 1 .0 V

Start and run engine warm, so that oxygen sensor reaches its operating temperature . An Increase

voltage signal must be displayed when enrichening the

(e .g . by acce!erat+nc ;vacuum hose on fuel pressure regula r

b) Checking Control Uni t

Run engine to operating temperature . Connect emission tester on exhaust test pipe in engine com-partment . Supply ground to plug receptacle on control unit end of disconnected oxygen sensor plu gwith help of auxiliary lead and observe the emission tester .

Ground

CO level must rise .

Caution : Only perform this test so long, until a change in CO level is recognized on the CO tester .

If a control unit does not process the ground signal, check its code (see page 2 - 47 in Test Plan )before replacing the control unit .

1987

40

TEST VALUES - LH-JETRONIC

928 S 4

TEST STEP 21 : ALTERNATOR / REGULATO R

Peak voltage of alternator could cause misfiring .

Take off drive belt on alternator, start engine -check alternator and regulato rif this eliminates the problem .

TEST VALUES LH-JETRONIC

928 5 4

INFORMATION FOR CHECKING IDLE SPEED AND IDLE SPEED C O

a) Idle Speed

The engine of 928 S 4 cars has adaptive idle speed volumetric efficiency control since 1987 models .This means the omission of idle speed adjustments for all versions . Idle speed can now only bechecked .On a warm engine it is : 675 ± 25 rpm .

b) Idle Speed CO for Cars without Cat . Cony .

CO adjustments on air flow sensor of 928 S 4engines are no longer possible . A potentiometer ,with which the CO level can be changed, i smounted on the holder of control units fo rthis purpose .

Following requirements must be fulfilled fo rCO level adjustments .

- Engine at operating temperature-- Air injection disconnected--- All electric equipment switched of f- Engine and ignition in perfect conditio n- CO tester at operating temperature, cali -

brated and adjusted

Adjustment : 0 .5 - 1 .5 % COat 675 ± 25 rpm and ignition timin g10 ± 20 before TDC .

Make sure that adapter plug 91 1 .612 .422 .00is connected on oxygen sensor connecting lea dof cars without catalytic converters, in orde rto avoid dispersion (see wiring diagram) .

A - TDC sende rB - CO test pipes

1957

2 -42

TEST VALUES - LH,IETRONIC

9285 4

c) Idle Speed CO for Cars with Catalytic Converter

In these cars there is adaption of the idle speed CO level in addition to adaption of the idle speed ,so that only the actual condition can be checked on such cars . The potentiometer is also omitte don the holder of control units because of this .Following requirements must be fulfilled for CO level checking .

- Engine at operating temperature- Oxygen sensor plug connected- All electric equipment switched of f- Engine and ignition in perfect condition-- CO tester at operating temperature, calibrated and adjusted

Test value: q .4 - 1 .2 % COat 675 ± 25 rpm and ignition timing 10 ± 2° before TIC .

After disconnection of control unit plugs or disconnecting the battery the engine must be ru nat idle speed afterwards at least 10 minutes, before a test of these values can be carried outagain .

S ; M

S1987 2-43

IDLE SPEED HC VALUES FOR PORSCHE CARS

9285 4

Values Applicable Worldwide:

75 Model, 76 Model '77 Model 78 Model 79 Model '80/'81 Mod . '821'83 Mod . 84-87 Mod .

911 911 911 911 SC 911 SC 911 SC 911 S C

1300 ppm ) (300 ppm l (300 ppm) (300 ppm) (260 ppm) (260 ppm) 300 ppm

911 S(300 ppm)

Carrer a1500 ppm)

Carrera(300 ppm)

930 Turbo(300 ppm)

911 Turb o1250 ppm)

911 Turb o(250 ppmY

911 TurboC 300 pp m

Carrera 930 Turbo 930 Turbo 924 924

1 924 92 4

1500 ppm) (300 ppm) (300 ppm) (400 ppm )1

(280 ppm) (280 ppm) 300 ppm a ao a

930 Turbo 924 924 928 924 Turbo 924 Turbo 924 Turbo o in

(300 ppm) (400 ppm) (400 ppm) (300 ppm) 4340 ppm) (340 ppm) 340 ppm VfV1

C 0928 928 928 U

(290 ppm) (310 ppm) C 300 ppm u u

0 . m928 S 928 S

T 03 u(310 ppm)

M .C .C300 ppmQ 3 3

9444 300 ppm

Please apply these figures with the following limitations.

1. Idle speed CO, ignition timing and idle speed must be adjusted to specifications .

2. As for all idle speed CO tests secondary air injection must be disconnected if applicable to car.

3. There is surely a fault in the mixture control unit/injection pump, spark plug or fuel injector ,if specified HC values are exceeded . On the other hand there could even be a fault when H Cvalues are too low . Consequently engine running at idle speed, etc ., must still be used as criteriafor evaluatiop.

A

E

2 - 441987

CONTROL UNITS -- CODES

928 S 4

Wiring Diagram Version Porsche Number

ECE,

Manual Transrn .

without catalytic converter

928 .607 .431 .00e 06040 2 1

~70503 0 ~

ECE,

Autom, Transm .

without catalytic converter

928 .607 .432 .00• ,

•

•

\i~iC- •7 a3

Worldwide,

Manual Transm .

with catalytic converter

928 .607 .433,00

Worldwide,

Autom . Transm -

with catalytic convener

928 .607 .434.00r, t

.~

Australia, Manual Transmission 928 .607 .435 .00

0

z • :Ob ®l -

5 O :~ o0

Australia, Automatic Transm . 928 .607 .436,00

l

080F • ,1 o0