Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Engine ...

Volkswagen B3 Passat Diagnosis, Fault Memory - Passat D2 Diagnosis, Fault Memory (Page GR-D2)

Engine code 9A Control units WITHOUT functions 04 and 08 CIS-E Motronic system electrical testing self diagnosis troubleshooting underhood component layout Fault code table Fault memory erasing reading Output checks diagnosis VAG 1551 Diagnostic Tester connecting VAG 1598 test box connecting description

Engine code 9A Control units WITH functions 04 and 08 Automatic transmission 096 returning to basic setting CIS-E Motronic system electrical testing troubleshooting underhood component layout Fault code table Fault memory erasing

reading Function 08 (VAG 1551, measuring value block) activating channel 1, interpreting channel 2, interpreting channel 3, interpreting channel 4, interpreting channel 5, interpreting channel 6, interpreting channel 7, interpreting channel 8, interpreting channel 9, interpreting channel 10, interpreting general information Output checks diagnosis Self-diagnosis general information technical data VAG 1551 Diagnostic Tester connecting selectable functions VAG 1598 test box connecting description

Volkswagen B3 Passat Diagnosis, Fault Memory - Passat CIS-E Motronic, self-diagnosis (Page D2-05-1)

Note Look under General for information about the test equipment, how to hook it up and how to use it. To use the information in this manual you need the right wiring diagram. See wiring diagrams.

CIS-E Motronic, self-diagnosis The procedures in this section apply to the following control units ONLY: 893 907 E, F, L, AND M These procedures are identified at the bottom of each page by the boxed footer: ECU without 04 and 08 functions For other (later) ECU's see next index. The CIS-E Motronic control unit (J 204) features Self-Diagnosis (SD) capability. If problems occur at monitored sensors or components, they are stored in Fault memory. The self diagnosis must be initiated and the stored fault(s) recalled with the tester VAG 1551. The VAG 1551 tester can tap into the Motronic ECU memory via remote diagnostic terminals beneath the center console in front of the shift lever. Faults that occur only occasionally are stored as sporadic faults.

CAUTION! Faults related to emissions and safety are stored in a permanent memory which must be intentionally erased after faults have been eliminated or repaired. The CIS-E Motronic control unit is also equipped with an output check diagnosis function.

ECU without 04 and 08 functions

Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Fuel injection system, underhood component layout (Page D2-10-1)

Note The CIS-E Motronic control unit contains a fault memory. Display the contents of the fault memory before beginning any repairs. See Repair Group D2 for additional information. WARNING! Fire hazard. Do NOT smoke or have anything in area that can ignite fuel.

CAUTION! During checking and adjusting, system limits are sometimes exceeded. These values will be recognized and stored as faults by the control unit. After all checks and adjustments have been performed, the fault memory should be cancelled. See Repair Group D2 for additional information. This Repair Group only covers the fuel related components of the CIS-E Motronic system. See Repair Group 28 for ignition components.



1 - Harness connector for Oxygen sensor on right engine mount 2 - Throttle body throttle screw must be turned in completely 3 - CIS-E Motronic control unit (J 204) 4 - Intake air temperature sensor (G 72) California only for monitoring function of EGR system 5 - EGR valve (Exhaust Gas Recirculation) California only 6 - CO tap tube 7 - Idle stabilizer valve (N 71) 8 - Power output stage (N 70) (of Ignition coil) 9 - Ignition coil 10 - 6 pin harness connector 11 - Ignition distributor with Hall sender 12 - Vacuum amplifier (EGR system) California only 13 - Ignition timing sensor (G 4) on cylinder number 4 ignition wire 14 - Thermopneumatic valve (EGR system) California only 15 - Coolant temperature sensor (G 62) 16 - Cold start valve (N 17) 17 - Knock sensor I (G 61) 18 - Fuel Injector 19 - Knock sensor 11 (G 66) 20 - Control flap for intake air pre-heating 21 - Differential pressure regulator (N 73) 22 - Fuel distributor 23 - Charcoal canister below air filter 24 - Air filter 25 - Potentometer 26 - Fuel pressure regulator 27 - Air flow sensor 28 - Solenoid valves 1 and 11 (N 80, N 115) for carbon canister 29 - Spark plug

30 - Harness connector for throttle switches (F 60, F 81)


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat CIS-E Motronic system, troubleshooting (Page D2-20-1)

verify complaint satisfy tuning requirements and adjustments If the problem still exists: find "symptom" in numbered top section scan the vertical column for ALL X's read across from the X to determine possible cause look up section for appropriate repair information or refer to index of Repair Group indicated

* Also see section D2-90



Troubleshooting verify complaint satisfy tuning requirements and adjustments If the problem still exists: find "symptom" in numbered top section scan the vertical column for ALL X s read across from the X to determine possible cause look up section for appropriate repair information or refer to index of indicated Repair Group

Also see section D2-90



Troubleshooting verify complaint satisfy tuning requirements and adjustments If the problem still exists: find "symptom" in numbered top section scan the vertical column for ALL X's read across from the X to determine possible cause look up section for appropriate repair information or refer to index of indicated Repair Group

* Also see section D2-90 ** Also see section D2-50 to perform output check diagnosis





Volkswagen B3 Passat Diagnosis, Fault Memory - Passat VAG Tester 1551, connecting (Page D2-30-1)

Requirements fuses 15, 18, and 21 OK A/C switched OFF engine ground connections OK, near ignition distributor, at engine block and the ground strap between the cylinder head and the ignition coil power output stage switch OFF ignition remove shift lever knob remove console cover

connect VAG 1551 with adaptor cable VAG 1551/1 as follows connect black wire to black diagnostic connector 1 connect white wire to white diagnostic connector 2 blue wire not used VAG - Self Diagnosis 1 - Rapid data transfer*

HELP

Display alternately appears as shown:

VAG - Self Diagnosis 2 - Blink code output*

HELP

Notes: For additional operating instructions push the HELP key.

If no display appears, check the voltage supply to the tester.


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Fault memory, reading (Page D2-40-1)

Check Fault memory After connecting the VAG 1551 tester, the display alternates between the following operating modes: 1 - Rapid Data Transfer 2 - Blink Code Output turn on VAG 1551 printer with "print" button indicator lamp in button lights up switch ON ignition Rapid data transfer Insert address word XX

HELP

press button 1 to select operating mode "Rapid data transfer" display will appear as shown Rapid data transfer 01 - Engine electronics

Q

press buttons 0 and 1 to select "ENGINE ELECTRONICS" display will appear as shown press Q button to enter input Rapid data transfer Tester sends address word 01

display will come on briefly to indicate it has sent the address word 01 (check control unit versions) 8AO907404 Coding 00

MOTOR

then the engine control unit will respond with an identification display which shows the part number, what system it controls, and when it was coded. If display appears as shown instead: Rapid data transfer Control unit does not answer!

HELP

press HELP key to print out a list of possible failures - after eliminating causes of failure repeat all inputs from the beginning to obtain the engine control unit identification screen...then proceed Rapid data transfer

HELP

Select Function XX

press button display will appear as shown



Rapid data transfer 02 - Check fault memory

Q

press "0" and "2" buttons to select Function 02 "Check Fault memory" display will appear as shown 2 faults recognized!

or No faults recognized

press Q button to enter input display will appear as shown press button stored faults are displayed and printed consecutively After display and print out of the last fault press button select Function 06 to End Output, and press the Q key to enter that selection correct faults using the fault code table, electrical testing table, wiring diagrams, and output check diagnosis function Multiple faults may be related, e.g.: low idle speed due to an inoperative idle stabilizer may also result in a Hall sender fault being generated. For vehicles with an automatic transmission, you MUST return the Digimat system to the basic setting after the following repairs: engine removal or replacement removal/replacement/adjustment of the throttle body, throttle cable, or throttle valve potentiometer removal or replacement of the transmission ECU see Section D2-110 for additional information If there is a complaint that has not registered a fault in the self diagnosis memory, perform further testing as per the troubleshooting guide.


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Fault memory, erasing (Page D2-50-1)

after repairing any faults, follow the previous procedure to check Fault memory After display and print out of the last fault: Rapid data transfer Select function XX

HELP

press button display will appear as shown Rapid data transfer 05 - Erase Fault memory

Q

press "0" and "5" buttons to select Function 05 "Erase Fault memory" display will appear as shown Rapid data transfer Fault memory is erased

press Q button to enter input display will appear as shown the Fault memory is now erased It display appears as shown instead ATTENTION: Fault memory is not interrogated

follow work procedure sequentially, i.e., first recall faults from memory press the key to continue select Function 06 to End Output, and press the Q key to enter that selection test drive vehicle for at least 5 minutes During test drive coolant temperature must reach 80°C (176°F) minimum engine speed must exceed 3000 RPM at least once accelerator pedal must be fully depressed at least once

CAUTION! After test drive, allow engine to idle for at least 2 minutes before checking Fault memory recall Fault memory, verify that all faults have been corrected


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Output check diagnosis (Page D2-60-1)

Note The following components (in the sequence given) can be checked using this procedure. 1 - Differential pressure regulator (N 73) 2 - Carbon canister frequency valve (N 80) 3 - Idle stabilizer valve (N 71) 4 - Cold-start valve (N 17)

After connecting the VAG 1551 tester, the display alternates between the following operating modes: 1 - Rapid Data Transfer 2 - Blink Code Output switch multimeter US 1119 (or equivalent) to Amps range connect multimeter to differential pressure regulator using VAG 1315A/1 test adaptor switch ON ignition Rapid data transfer Insert address word XX

HELP


Q

press buttons 0 and 1 to select "ENGINE ELECTRONICS" display will appear as shown press Q button to enter input Rapid data transfer Tester sends address word 01

Q

display will come on briefly to indicate it has sent the address word 01 (check control unit versions) 8AO907404 Coding 00

MOTOR

then the engine control unit will respond with an identification display which shows the part number, what system it controls, and where it was coded (as shown in example)



Rapid data transfer Control unit does not answer!

HELP

If display appears as shown instead: press HELP key to print out a list of possible failures - after eliminating causes of failure repeat all inputs from the beginning to achieve the engine control unit identification screen . . . then proceed Rapid data transfer Select function XX

HELP

press button display will appear as shown Rapid data transfer 03 - output check diagnosis

Q

press "0" and "3" buttons to select Function 03: "output check diagnosis" display will appear as shown Output check diagnosis Differential pressure regulator (N 73)

press Q button to enter input display will appear as shown observe control current on multimeter control current must fluctuate from 0 to 100 mA If NO check wiring using wiring diagram check differential pressure regulator resistance If wiring and resistance measurement OK replace CIS-E Motronic control unit (J 204) Output check diagnosis Carbon canister frequency valve (N 80)

press button display will appear as shown frequency valve must click If valve does not click check control as follows



remove harness connector from frequency valve connect LED tester US 1115 (VAG 1527B) to harness connector using VW 1594 adaptor kit LED must flash If LED flashes replace frequency valve (N 80) If LED does NOT flash check wiring If wiring OK replace CIS-E Motronic control unit (J 204) Output check diagnosis Idle stabilizer valve (N 71)

press button display will appear as shown idle stabilizer valve must click If NO check control as follows switch OFF ignition disconnect idle stabilizer valve harness connector

connect valve to harness connector using adaptor wires VW 1594/1, /2 and /19 connect LED tester to adaptor wire VW 1594/19 using adaptor VW 1594/15 repeat output check diagnosis from the beginning When display: "Idle stabilizer valve (N 71)" has been obtained LED must flash If LED flashes replace idle stabilizer valve If LED does NOT flash switch multimeter US 1119 (or equivalent) to resistance range measure idle stabilizer valve resistance must be 4 to 12 Ohms check wiring If wiring OK replace CIS-E Motronic control unit (J 204)



Output check diagnosis Cold-start valve (N 17)

press button display will appear as shown open throttle slightly cold-start valve must click Note The valve only is activated ten times to avoid "flooding" the engine. To repeat this check, the output check diagnosis must be repeated from the beginning.

If the valve does not click, check control as follows disconnect cold-start valve harness connector connect LED tester to harness connector using adaptor kit VW 1594 perform output check diagnosis again from the beginning When display "cold-start valve (N 17)" is obtained open throttle valve slightly LED must flash ten times If LED flashes replace cold-start valve If LED does NOT flash check wiring If wiring OK replace CIS-E Motronic control unit (J 204) press the key to continue select Function 06 to End Output, and press the Q key to enter that selection


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Fault code, table (Page D2-70-1)

Note before replacing components coded as faulty, first check the wiring and ground connections to these components using the proper wiring diagram to check wiring, see "CIS-E Motronic system, electrical tests", section D2-90 blink code (4 digit) does not appear in display when in rapid data mode Example: Fault indicator code 65535

Blink code (if present) 1111

* Note for Fault Code 1231: Some VAG 1551 Diagnostic Testers will display component code (G68) for this fault. FOR THOSE TESTERS: the display is INCORRECT. The CORRECT component code is (G54).










Volkswagen B3 Passat Diagnosis, Fault Memory - Passat VAG 1598 Test box, description (Page D2-80-1)

The VAG 1598 Test box and adaptor set was introduced in July of 1989. It consists of a main harness with test box (that universally connects to all of the adaptor harnesses) and a set of adaptor harnesses. A hardshell storage case is provided to protect the set when not in use. The VAG 1598 is used in conjunction with several other pieces of test equipment consisting of: US 1119 (or equivalent) multimeter US 1115 (VAG 1527B) LED tester VW 1594 adaptor kit Note New adaptor harnesses will be made available for the VAG 1598 in the future as new applications require them. VAG 1598 advantages: the fragile terminals in the control unit connector no longer risk damage from test leads and probe connections. Connections formerly made on the control unit connector are not made on the VAG 1598 Test box which has large conveniently accessible terminals raised, highly visible numbers on the Test box eliminate any uncertainty as to connector terminal numbering certain components (e.g. Hall sender) can now be checked dynamically (engine running) electronically checking miniature and unusual size terminals is now made possible regardless of terminal size standard sized adaptors are used to make and test all connections resulting in dependable, accurate measurements


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat VAG 1598 Test box, connecting (Page D2-90-1)

Example: CIS-E Motronic control unit select the appropriate adaptor harness from the list (based on the connector you wish to connect to) for this example use adaptor harness VAG 1598/3 connector adaptor harness VAG 1598/3 to main test box harness by joining the two rectangular connectors, then tighten via knobs on main harness connector Note The rectangular connector which is on every adaptor cable can only be installed one way. Examine the connector and you will see where the threaded connectors of the Test box harness attach to the adaptor connector.

disconnect CIS-E Motronic control unit harness connector 1 from control unit 2 connect test adaptor VAG 1598/3 male connector to control unit harness connector 1 Note In this example the wiring up to the control unit is being checked statically, making it unnecessary to connect the control unit to the adaptor harness; however, for dynamic checks you will have to connect the control unit.


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat CIS-E Motronic system, electrical testing (Page D2-100-1)

Requirements before testing voltage supply (alternator, battery) OK starter operates OK wiring and connectors OK (not corroded, terminals properly seated, etc.) fuses 15 and 18 OK CIS-E Motronic control unit ground wires OK (near ignition distributor connection) fuel pumps and fuel pump relay OK check control unit for stored faults using VAG 1551, eliminate faults as necessary Note Before replacing a component whose measured value deviates from the specified value; first check all connections and wiring to the component using the wiring diagram then check component resistance (if possible). use the following test instruments to perform the electrical tests in this section: US 1119 or equivalent multimeter, US 1115 (VAG 1527B) LED tester, VW 1594 adaptor kit, VAG 1598 Test box with the VAG 1598/3 adaptor cable connect test instruments to Test box terminals using VW 1594 adaptor kit terminal numbers of component connectors and terminal numbers on Test box are the same the specifications given are valid ONLY when measured within an ambient temperature range of 0° to + 40°C (+32° to + 104°F)

CAUTION! Perform the following electrical tests with great care. The CIS-E Motronic control unit could be destroyed if the following precautions are NOT observed: ALWAYS switch the multimeter to the desired units and range of measurement (Volt, Ohms, etc.) BEFORE making connections to the Test box do NOT connect or disconnect adaptors/test instruments to the Test box while the ignition is switched ON



switch OFF ignition switch multimeter US 1119 (or equivalent) to 20 Volts DC range disconnect CIS-E Motronic control unit connect VAG 1598 Test box to control unit harness connector using VAG 1598/3 adaptor cable CIS-E Motronic control unit 1 is NOT connected during the following tests







Also see airflow sensor potentiometer dynamic test in Repair Group 25, page 25-180-1



CAUTION! Perform the following electrical tests with great care. The CIS-E Motronic control unit could be destroyed if the following precautions are NOT observed. ALWAYS switch the multimeter to the desired units and range of measurements (Volts, Ohms, etc.) BEFORE making connections to the Test box Do NOT connect or disconnect adaptors/test instruments to the Test box when the ignition is switched ON The following tests are performed with the control unit harness connector AND the control unit connected to the VAG 1598/3 adaptor cable). switch OFF ignition connect free end of VAG 1598/3 adaptor cable to control unit switch multimeter US 1119 (or equivalent) to 20 Volt range


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Automatic transmission 096, returning to basic setting (Page D2-110-1)

Note You MUST return the Digimat system to the basic setting after the following repairs: engine removal or replacement removal/replacement/adjustment of the throttle body, throttle cable, or throttle valve potentiometer removal or replacement of the transmission ECU Perform the basic setting anytime you are not sure if it has been done. It only takes a moment and will ensure that you do not receive a complaint due to someone else's oversight. After connecting the VAG 1551 tester, the display alternates between the following operating modes: 1 - Rapid Data Transfer 2 - Blink Code Output switch ON ignition Rapid data transfer Insert address word XX

HELP

press button 1 to select operating mode "Rapid data transfer" display will appear as shown Rapid data transfer 02 - Transmission electronics

Q

press buttons 0 and 2 to select "Transmission electronics" display will appear as shown press Q button to enter input Rapid data transfer Tester sends address word 01

display will come on briefly to indicate it has sent the address word 01 (check control unit versions) 095927731 F Digimat Code 127

0569 WSC131071

then the transmission control unit will respond with an identification display which shows the part number, what system it controls, the EPROM programming level. and where it was coded




HELP

If display appears as shown instead: press HELP key to print out a list of possible failures - after eliminating causes of failure repeat all inputs from the beginning to achieve the transmission control unit identification screen . . . then proceed Rapid data transfer Select function XX

HELP

press button display will appear as shown Note Before performing the "return to basic setting" you must first determine that full accelerator pedal travel is present. Perform the following procedure to digitally display the throttle position and travel. Rapid data transfer 08 Read measuring value block

Q

press buttons 0 and 8 to select Function 08 "Read measuring value block" display will appear as shown Read measuring value block Input display group number XX

press Q button to enter input display will appear as shown Note The measuring block values can only be read with the tester program card /2 installed. Read measuring value block Q Input display group number 00

press 0 button two times display will appear as shown Read measuring value block 0 1 0 0 17 0 242 250 19

press Q button to enter input

3

Read measuring value block P 0.37V 0%

00000111

one of the 2 displays shown will appear, dependent upon the production level of the DIGIMAT transmission control unit To check accelerator travel observe displayed values first with pedal in idle position then in full-throttle position Read measuring value block 0 1 0 0 17 0 242 250 19

3

10 channel display, observe value in channel 2 (arrow) must read 0-2 (idle position) must read 253-255 (full throttle)



press

button

Read measuring value block 1 P 0.37V 0% 00000111

4 channel display, observe value in channel 3 (arrow) must read 0-1% (idle position) must read 99-100% (full throttle) If readings are not within specifications check throttle valve position with pedal at idle and full throttle positions must be fully closed at idle and wide open when pedal is fully depressed to floor If NO check accelerator cable condition and adjustment, adjust or replace if necessary If YES check throttle potentiometer adjustment, adjust or replace if necessary Rapid data transfer Select function XX

HELP

press button display will appear as shown Rapid data transfer 04 - Start basic setting

Q

press buttons 0 and 4 to select Function 04 "Basic setting" display will appear as shown Start basic setting Input display group number XX

HELP

press Q button to enter input display will appear as shown Start basic setting Input display group number 00

Q

press 0 button two times display will appear as shown System in basic setting

press Q button to enter input display will appear as shown depress accelerator pedal fully to floor for 5 seconds



After 5 seconds, with accelerator pedal fully depressed press key release accelerator pedal system has now been returned to the basic setting select Function 06 to End Output, and press the Q key to enter that selection


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat CIS-E Motronic, self-diagnosis (Page D2-120-1)

The procedures in this section apply to the following control units ONLY: Starting October 1990: 49 States & Canada 8A0 907 404 California 893 907 404Q These procedures are identified at the bottom of each page by the boxed footer: ECU with 04 and 08 functions For other (later) ECU's see next index. The CIS-E Motronic control unit (J 204) features Self-Diagnosis (SD) capability. If problems occur at monitored sensors or components, they are stored in Fault memory. The self diagnosis must be initiated and the stored fault(s) recalled with the tester VAG 1551. The VAG 1551 tester can tap into the Motronic ECU memory via remote diagnostic terminals beneath the center console in front of the shift lever. Faults that occur only occasionally are stored as sporadic faults and are indicated in the VAG 1551 display by "SP". If a Fault does not occur within 5 engine starts or for exhaust related faults within the next 50 starts, the sporadic fault will automatically be erased.

CAUTION! Faults related to emissions and safety are stored in a permanent memory which must be intentionally erased after faults have been eliminated or repaired. The CIS-E Motronic control unit is also equipped with an output check diagnosis function.

ECU with 04 and 08 functions


Note The CIS-E Motronic control unit contains a fault memory. Display the contents of the fault memory before beginning any repairs. WARNING! Fire hazard. Do NOT smoke or have anything in area that can ignite fuel. CAUTION! During checking and adjusting system limits are sometimes exceeded. These values will be recognized and stored as faults by the control unit. Alter all checks and adjustments have been performed the fault memory should be erased.



1 - Harness connector for Oxygen sensor on right engine mount 2 - Throttle body throttle screw must be turned in completely 3 - CIS-E Motronic control unit (J 204) 4 - Intake air temperature sensor (G 72) California only for monitoring function of EGR system 5 - EGR valve (Exhaust Gas Recirculation) California only 6 - CO tap tube 7 - Idle stabilizer valve (N 71) 8 - Power output stage (N 70) (of ignition coil) 9 - Ignition coil 10 - 6 pin harness connector 11 - Ignition distributor with Hall sender 12 - Vacuum amplifier (EGR system) California only 13 - Ignition timing sensor (G 4) on cylinder number 4 ignition wire 14 - Thermopneumatic valve (EGR system) California only 15 - Coolant temperature sensor (G 62) 16 - Cold start valve (N 17) 17 - Knock sensor I (G 61) 18 - Fuel injector 19 - Knock sensor II (G 66) 20 - Control flap for intake air pre-heating 21 - Differential pressure regulator (N 73) 22 - Fuel distributor 23 - Carbon canister below air filter 24 - Air filter 25 - Potentiometer 26 - Fuel pressure regulator 27 - Air flow sensor 28 - Solenoid valves I and II (N 80 N 115) for carbon canister 29 - Spark plug

30 - Harness connector for throttle switches (F 60, F 81)


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Self Diagnosis, Technical Data (Page D2-140-1)

1) Erased after 5th engine start, if faults no longer occur. 2) For vehicles 10.90 (beginning with Parts No. of CIS-E Motronic control unit US-49 states and Canada 8A0 907 404, California 893 907 404Q) before idle adjustment or ignition timing point return system to basic setting. See Repair Group 25 or 28.


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat VAG 1551 Diagnostic Tester, selectable functions (Page D2-150-1)

(X) = also possible. 1) Starting October 1990 Production with control unit: 49 States and Canada 8A0 907 40 California 893 907 404 Q.



verify complaint satisfy tuning requirements and adjustments If the problem still exists: find "symptom" in numbered top section scan the vertical column for ALL X's read across from the X to determine possible cause look up section for appropriate repair information or refer to index of Repair Group indicated

* Also see section D2-200











Volkswagen B3 Passat Diagnosis, Fault Memory - Passat VAG Tester 1551, connecting (Page D2-170-1)

Requirements fuses 15, 18, and 21 OK A/C switched OFF engine ground connections OK, near ignition distributor, at engine block and the ground strap between the cylinder head and the ignition coil power output stage switch OFF ignition remove shift lever knob remove console cover

connect VAG 1551 with adaptor cable VAG 1551/1 as follows connect black wire to black diagnostic connector 1 connect white wire to white diagnostic connector 2 blue wire not used VAG - Self Diagnosis 1 - Rapid data transfer*

HELP

Display must alternately appear as shown: VAG - Self Diagnosis 2 - Blink code output*

HELP

If no display appears: check the voltage supply to the tester verify that the wiring polarity is correct, repair or replace as necessary Note

For additional operating instructions push the HELP key.



Check Fault memory After connecting the VAG 1551 tester, the display alternates between the following operating modes: 1 - Rapid Data Transfer 2 - Blink Code Output turn on VAG 1551 printer with "print" button indicator lamp in button lights up switch ON ignition Rapid data transfer Insert address word XX

HELP


Q

press buttons 0 and 1 to select "Engine electronics" display will appear as shown press Q button to enter input Rapid data transfer Tester sends address word 01

HELP

display will come on briefly to indicate it has sent the address word 01 (check control unit versions) 8A0907404 Coding 00

MOTOR

then the engine control unit will respond with an identification display which shows the part number, what system it controls, and where it was coded If display appears as shown instead: Rapid data transfer Control unit does not answer!

HELP

press HELP button to print out a list of possible failures - after eliminating causes of failure repeat all inputs from the beginning to obtain the engine control unit identification screen . . . then proceed Rapid data transfer

HELP

Select function XX

press button display will appear as shown



Rapid data transfer 02 - Check fault memory

Q

press "0" and "2" buttons to select Function 02 "Check Fault memory" display will appear as shown 2 faults recognized!

press Q button to enter input display will appear as shown No fault recognized

or (example only) press button stored faults are displayed and printed consecutively After display and print out of the last fault press button select Function 06 to End output, and press the Q button to enter that selection correct faults using the fault code table, electrical testing table, wiring diagrams, and output check diagnosis function Multiple faults may be related, e.g.: low idle speed due to an inoperative idle stabilizer may also result in a Hall sender fault being generated. For vehicles with an automatic transmission, you MUST return the Digimat system to the basic seeing after the following repairs: engine removal or replacement removal/replacement/adjustment of the throttle body, throttle cable, or throttle valve potentiometer removal or replacement of the transmission ECU see section D2-370 for additional information



CAUTION! If ignition is switched off or engine is left running between reading and erasing Fault memory; Fault memory will not be erased. after repairing any faults, follow the previous procedure to check Fault memory After display and print out of the last fault: Rapid data transfer Select function XX

HELP

press button display will appear as shown Rapid data transfer 05 - Erase Fault memory

HELP

press "0" and "5" buttons to select Function 05 "Erase Fault memory" display will appear as shown Rapid data transfer Fault memory is erased

press Q button to enter input display will appear as shown the Fault memory is now erased If display appears as shown instead: ATTENTION! Fault memory is not interrogated

follow work procedure sequentially, i.e., first recall faults from memory press the key to continue select Function 06 to End output, and press the Q button to enter that selection test drive vehicle for at least 5 minutes



During test drive coolant temperature must reach 80.C (176°F) minimum engine speed must exceed 3000 RPM at least once accelerator pedal must be fully depressed at least once

CAUTION! After test drive, allow engine to idle for at least 2 minutes before checking Fault memory. read Fault memory, verify that all faults have been corrected



Requirements fuses 15 and 21 OK idle switch OK (closed) ground wire connections OK (at intake manifold and battery) ignition switched OFF

Note The following components (in the sequence given) can be checked using this procedure. 1 - Differential pressure regulator (N 73) 2 - Carbon canister frequency valve (N 80) 3 - Idle stabilizer valve (N 71) 4 - Cold-start valve (N 17)

After connecting the VAG 1551 tester, the display alternates between the following operating

modes: 1 - Rapid Data Transfer 2 - Blink Code Output switch multimeter US 1119 (or equivalent) to Amps range connect multimeter to differential pressure regulator using VAG 1315A/1 test adaptor switch ON ignition display must appear positive, if not, reverse meter leads Rapid data transfer Insert address word XX

HELP


Q

press buttons 0 and 1 to select "Engine electronics" display will appear as shown press Q button to enter input



Rapid data transfer Tester sends address word 01

display will come on briefly to indicate it has sent the address word 01 (check control unit versions) 8A0907404 Coding 00

MOTOR

then the engine control unit will respond with an identification display which shows the part number, what system it controls, and where it was coded (as shown in example) Rapid data transfer Control unit does not answer!

HELP

If display appears as shown instead press HELP button to print out a list of possible failures-after eliminating causes of failure repeat all inputs from the beginning to achieve the engine control unit identification screen then proceed Rapid data transfer Select function XX

HELP

press button display will appear as shown Rapid data transfer 03 - Output check diagnosis

Q

press "0" and "3" buttons to select Function 03 "Output check diagnosis" display will appear as shown Output check diagnosis Differential pressure regulator (N 73)

press Q button to enter input display will appear as shown observe control current on multimeter control current must fluctuate from 0 to 100 mA If NO check wiring using wiring diagram

check differential pressure regulator resistance If wiring and resistance measurement OK replace CIS-E Motronic control unit (J 204) Output check diagnosis Carbon canister frequency valve (N 80)

press button display will appear as shown frequency valve must click If valve does not click check control as follows



remove harness connector from frequency valve connect LED tester US 1115 (VAG 1527B) to harness connector using VW 1594 adaptor kit LED must flash If LED flashes replace frequency valve (N 80) If LED does NOT flash check wiring If wiring OK replace CIS-E Motronic control unit (J 204) Output check diagnosis Idle stabilizer valve (N 71)

press button display will appear as shown idle stabilizer valve must click If NO check control as follows switch OFF ignition disconnect idle stabilizer valve harness connector

connect valve to harness connector using adaptor wires VW 1594/1, /2 and /19 connect LED tester to adaptor wire VW 1594/19 using adaptor VW 1594/15 repeat output check diagnosis from the beginning When display: "Idle stabilizer valve (N 71)" has been obtained LED must flash If LED flashes replace idle stabilizer valve If LED does NOT flash switch multimeter US 1119 (or equivalent) to resistance range measure idle stabilizer valve resistance must be 4 to 12 Ohms check wiring If wiring OK replace CIS-E Motronic control unit (J 204)



Output check diagnosis Cold-start valve (N 17)

press button display will appear as shown open throttle slightly cold-start valve must click Note The valve is only activated ten times to avoid flooding the engine. To repeat this check, the output check diagnosis must be repeated from the beginning.

If the valve does not click, check control as follows disconnect cold-start valve harness connector connect LED tester to harness connector using adaptor kit VW 1594 perform output check diagnosis again from the beginning When display "Cold-start valve (N 17)" is obtained open throttle valve slightly LED must flash ten times If LED flashes replace cold-start valve If LED does NOT flash check wiring, section D2-360 Test Step 11 If wiring OK replace CIS-E Motronic control unit (J 204) press the key to continue Rapid data transfer Select function XX

HELP

display will appear as shown

press 0 and 6 buttons Rapid data transfer 06 - Ending output

Q

display must appear as shown press Q key to enter input



Note before replacing components coded as faulty, first check the wiring and ground connections to these components using the proper wiring diagram to check wiring, see "CIS-E Motronic system, electrical tests", section D2-360 blink code (4 digit) does not appear in display when in rapid data mode Example: Fault indicator code 65535

Blink code (if present) 1111

* Note for fault code 1231: Some VAG 1551 Diagnostic Testers will display component code (G 68) for this fault. FOR THOSE TESTERS: the display is INCORRECT. The CORRECT component code is (G 54).










Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Test value block (Function 08), activating (Page D2-220-1)

For control units starting October 1990: 49 States and Canada: 8A0 908 404 California: 893 907 404 Q Note When using Function 08 "Reading measuring value block" only one channel can be displayed at a time. The channel is indicated by the 00 portion of the display. Requirements fuses 15 and 31 OK ECU (at intake manifold) and battery ground connections OK

connect VAG 1551 Diagnostic Tester using adaptor cable VAG 1551/1 as follows first connect black terminal of tester to black diagnostic connector 1 alternating displays will appear as shown VAG - Self Diagnosis 1 - Rapid data transfer*

HELP

or VAG - Self Diagnosis 2 - Blink code output*

HELP

connect white terminal of tester to brown or white diagnostic connector If no display (no power to tester) do not connect white terminal of tester check diagnostic connector voltage supply using wiring diagram, repair or replace as

necessary. start engine and let idle observe display on VAG 1551 Diagnostic Tester press 0 and 1 buttons to obtain "rapid data transfer" mode


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat Test value block (Function 08), activating (Page D2-220-2)

press Q button to enter input push button press 0 and 8 buttons to obtain Function 08 "Read measuring value block" press Q button to enter input display will appear as shown Read measuring value block Insert display group number XX

HELP

press 0 button twice to select "Indicator Group 00" display will appear as shown Read measuring value block Input indicator group number 00

Q

press Q button to enter input display will appear as shown (values 1 through 10 = channels) Reading measuring value block 1 2 3 4 5 6 7 8

9

10

Notes indicator group 00 shows only "Reading measuring value block" values are shown in decimal form. when the 08 Function is selected, DIS (digital idle stabilization) and the carbon canister solenoid valve 1 continue to operate. the channel test values are continuously displayed regardless of RPM range. Note For a detailed description of channels see sections D2-230 to D2-330. push button display will appear as shown Rapid data transfer Select function XX

HELP

push 0 and 6 buttons to select Function 06 "Ending output" display will appear as shown Rapid data transfer 06 - Ending output


Q


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat VAG 1551 Function 08, channel identification (Page D2-230-1)


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat VAG 1551 Function 08, channel 1 interpretation (Page D2-240-1)



CAUTION! If adjustments are required, use the Repair Manual procedures not the VAG 1551.





This number is not adjustable. If not within working range you must check all other engine adjustments, vacuum leaks, and the mechanical condition of the engine. Since this is an adaptive value it will take approximately 4 minutes or more to adapt itself after a correction is made.



These values are not adjustable. If not within working range you must check all other engine adjustments, vacuum leaks, and the mechanical condition of the engine.



A Value of 50 Equals + 10 Milliamps of Differential Pressure Regulator Current A Value of 0 Equals 0 Milliamps of Differential Pressure Regulator Current A Value of 206 Equals -10 Milliamps of Differential Pressure Regulator Current If adjustments are required, follow the Repair Manual procedures. Adjustments cannot be made using the VAG 1551 alone.



A Value of 228 Equals +10 Milliamps of Differential Pressure Regulator Current A Value of 128 Equals 0 Milliamps of Differential Pressure Regulator Current A Value of 228 Equals -10 Milliamps of Differential Pressure Regulator Current



This is a digital signal and only represents and on/off signal



Channel 9, interpreting Channel 9 provides the technician with essential information that would have to be verified manually before performing the basic engine settings. The ECU scans the system for certain conditions that must be met or for certain components that must be present or operative. It then assigns the numerical values (listed in the table below) to these conditions or components and adds them together to create the display value. A value of zero will be assigned to conditions or components in the following chart that are NOT MET or NOT PRESENT.

Note By analyzing the value displayed in channel 9 (using simple addition or subtraction) you can easily determine if a component is present or not. Display Example Idle Switch Closed Auto Trans in Neutral A/C Compressor On Total

1 4 8

13

(Displayed in Channel 9)




Volkswagen B3 Passat Diagnosis, Fault Memory - Passat VAG 1598 Test box, description (Page D2-340-1)

The VAG 1598 Test box and adaptor set consists of a main harness with Test box (that universally connects to all of the adaptor harnesses) and a set of adaptor harnesses. A hardshell storage case is provided to protect the set when not in use. The VAG 1598 is used in conjunction with several other pieces of test equipment consisting of: US 1119 (or equivalent) multimeter US 1115 (VAG 1527B) LED tester VW 1594 adaptor kit Note New adaptor harnesses will be made available for the VAG 1598 in the future as new applications require them. VAG 1598 advantages: the fragile terminals in the control unit connector no longer risk damage from test leads and probe connections. Connections formerly made on the control unit connector are now made on the VAG 1598 Test box which has large conveniently accessible terminals raised, highly visible numbers on the Test box eliminate any uncertainty as to connector terminal numbering certain components (e.g. Hall sender) can now be checked dynamically (engine running) electronically checking miniature and unusual size terminals is now made possible regardless of terminal size standard sized adaptors are used to make and test all connections resulting in dependable, accurate measurements


Volkswagen B3 Passat Diagnosis, Fault Memory - Passat VAG 1598 Test box, connecting (Page D2-350-1)

Example: CIS-E Motronic control unit select the appropriate adaptor harness from the list (based on the connector you wish to connect to) for this example use adaptor harness VAG 1598/3 connector adaptor harness VAG 1598/3 to main test box harness by joining the two rectangular connectors, then tighten via knobs on main harness connector Note The rectangular connector which is on every adaptor cable can only be installed one way. Examine the connector and you will see where the threaded connectors of the Test box harness attach to the adaptor connector.

disconnect CIS E Motronic control unit harness connector 1 from control unit 2 connect test adaptor VAG 1598/3 male connector to control unit harness connector 1 Note In this example the wiring up to the control unit is being checked statically, making it unnecessary to connect the control unit to the adaptor harness; however, for dynamic checks you will have to connect the control unit.



Requirements before testing voltage supply (alternator, battery) OK starter operates OK wiring and connectors OK (not corroded, terminals properly seated, etc.) fuses 15, 18 and 2 OK CIS-E Motronic control unit ground wires OK (intake manifold ground connection) fuel pumps and fuel pump relay OK check control unit for stored faults using VAG 1551, eliminate faults as necessary Note Before replacing a component whose measured value deviates from the specified value; first check all connections and wiring to the component using the wiring diagram then check component resistance (if possible). use the following test instruments to perform the electrical tests in this section: US 1119 or equivalent multimeter, US 1115 (VAG 1527B) LED tester, VW 1594 adaptor kit, VAG 1598 Test box with the VAG 1598/3 adaptor cable connect test instruments to Test box terminals using VW 1594 adaptor kit terminal numbers of component connectors and terminal numbers on Test box are the same the specifications given are valid ONLY when measured within an ambient temperature range of 0° to + 40°C (+32° to + 104°F)

CAUTION! Perform the following electrical tests with great care. The CIS-E Motronic control unit could be destroyed if the following precautions are NOT observed: ALWAYS switch the multimeter to the desired units and range of measurement (Volt, Ohms, etc.) BEFORE making connections to the Test box do NOT connect or disconnect adaptors/test instruments to the Test box while the ignition is switched ON



switch OFF ignition switch multimeter US 1119 (or equivalent) to 20 Volts DC range disconnect CIS-E Motronic control unit connect VAG 1598 Test box to control unit harness connector using VAG 1598/3 adaptor cable CIS-E Motronic control unit 1 is NOT connected during the following tests

Note To test terminals 25 + 31 (for automatic transmission vehicles only); read Fault memory for automatic transmission see Repair Group D3 for additional information.





Also see airflow sensor potentiometer dynamic test in Repair Group 25, page 25-180-1





The following tests are performed with the control unit harness connector AND the control unit connected to the VAG 1598/3 adaptor cable). switch OFF ignition connect free end of VAG 1598/3 adaptor cable to control unit switch multimeter US 1119 (or equivalent) to 20 Volt range

CAUTION! Perform the following electrical tests with great care. The CIS-E Motronic control unit could be destroyed if the following precautions are NOT observed. ALWAYS switch the multimeter to the desired units and range of measurements (Volts, Ohms, etc.) BEFORE making connections to the Test box do NOT connect or disconnect adaptors/test instruments to the Test box when the ignition is switched ON

* Measure directly between actual ground point on manifold and terminal 35 of VAG 1598 Test box. ** If greater than 60 mV check ground connection at intake manifold and clean or repair as necessary



Note You MUST return the Digimat system to the basic setting after the following repairs: engine removal or replacement removal/replacement/adjustment of the throttle body, throttle cable, or throttle valve potentiometer removal or replacement of the transmission ECU Perform the basic setting anytime you are not sure if it has been done. It only takes a moment and will ensure that you do not receive a complaint due to someone else's oversight. After connecting the VAG 1551 tester, the display alternates between the following operating modes: 1 - Rapid Data Transfer 2 - Blink Code Output switch ON ignition Rapid data transfer Insert address word XX

HELP

press button 1 to select operating mode "Rapid data transfer" display will appear as shown Rapid data transfer 02 - Transmission electronics

Q

press buttons 0 and 2 to select "Transmission electronics" display will appear as shown press Q button to enter input Rapid data transfer Tester sends address word 02

display will come on briefly to indicate it has sent the address word 02 (check control unit versions) 095927731 F Digifant Code 127

0569 WSC131071

then the transmission control unit will respond with an identification display which shows the part number, what system it controls, the EPROM programming level, and where it was coded




HELP

If display appears as shown instead: press HELP key to print out a list of possible failures - after eliminating causes of failure repeat all inputs from the beginning to achieve the transmission control unit identification screen . . . then proceed Rapid data transfer Select function XX

HELP

press button display will appear as shown Note Before performing the "return to basic setting" you must first determine that full accelerator pedal travel is present. Perform the following procedure to digitally display the throttle position and travel. Rapid data transfer 08 - Read measuring value block

Q

press buttons 0 and 8 to select Function 08 "Read measuring value block" display will appear as shown Read measuring value block Input display group number XX

press Q button to enter input display will appear as shown Note The measuring block values can only be read with the tester program card /2 installed. Read measuring value block Input display group number 00

press 0 button two times display will appear as shown Read measuring value block 0 1 0 0 17 0 242 250 19 3


Q

Read measuring value block P 0.37V 0% 00000111

one of the 2 displays shown will appear, dependent upon the production level of the DIGIMAT transmission control unit



To check accelerator travel Read measuring value block 0 1 0 0 17 0 242 250 19 3

observe displayed values first with pedal in idle position then in full-throttle position 10 channel display, observe value in channel 2 (arrow) must read 0-2 (idle position) must read 253-255 (full throttle) press button Read measuring value block P 0.37V 0% 00000111

4 channel display, observe value in channel 3 (arrow) must read 0-1% (idle position) must read 99-100% (full throttle) If readings are not within specifications check throttle valve position with pedal at idle and full throttle positions must be fully closed at idle and wide open when pedal is fully depressed to floor If NO check accelerator cable condition and adjustment adjust or replace if necessary If YES check throttle potentiometer adjustment, adjust or replace if necessary Rapid data transfer Select function XX

HELP

press button display will appear as shown Rapid data transfer 04 - Start basic setting

Q

press buttons 0 and 4 to select Function 04 "Basic setting" display will appear as shown Start basic setting Input display group number XX

HELP

press Q button to enter input display will appear as shown

Start basic setting Input display group number 00

HELP

press 0 button two times display will appear as shown



System in basic setting

press Q button to enter input display will appear as shown depress accelerator pedal fully to floor for 5 seconds After 5 seconds, with accelerator pedal fully depressed press key release accelerator pedal system has now been returned to the basic setting select Function 06 to End output, and press the Q key to enter that selection
