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Interrogating and erasing fault memory > < Technical data for self-diagnosis

A4 Mk1

Motronic injection and ignition system (4-cyl.)
Self-diagnosis of Motronic system
Connecting and selecting functions for vehicle diagnostic, testing and information system VAS 5051 or fault reader V.A.G 1551

Test conditions

  • ● Fuses for engine electronics OK
  • ● Fuel pump relay OK.
 
A24-0028
  • ● Battery voltage at least 11 V
  • ● Earth connections on engine and gearbox OK.
  • ‒ Switch ignition off.
  • ‒ → Open rear ashtray and remove cover for diagnostic connector.
 
A24-0029
  • ‒ → Connect vehicle diagnostic, testing and information system VAS 5051 with diagnosis cable VAS 5051/1. As an alternative, connect fault reader V.A.G 1551 with diagnosis cable V.A.G 1551/3.
Warning!
  • ◆ When performing test-drives and checks, the vehicle diagnostic, testing and information system VAS 5051 as well as the fault reader V.A.G. 1551 may be secured only on rear seat, from where it is to be operated.
  • ◆ Please follow safety precautions

Note:

Only the procedure for self-diagnosis using fault reader V.A.G. 1551 is described below. For details of how to use the vehicle diagnostic, testing and information system VAS 5051, please refer to its operating manual.
 
→ Indicated in display
V.A.G - SELF DIAGNOSIS    HELP
1 - Rapid data transfer 1)
2 - Flash code output 1)

    1)    appears alternately

  • ‒ If no display appears, check diagnostic cables:

=> Current Flow Diagrams, Electrical Fault-Finding and Fitting Locations binder; Fault-finding programme: "Diagnostic wiring"

Depending on the function required (=> table of selectable functions Page 01-2):

  • ‒ Switch ignition on.
  • or
  • ‒ Start the engine.
  • ‒ Switch on fault-reader printer with the Print key
    (Warning lamp in key lights up).
  • ‒ Press key 1 for "Rapid data transfer".
 
→ Indicated on display:
Rapid data transfer    HELP
Enter address word XX

 
→ Press keys 0 and 1 for address word "Engine electronics" and confirm entry by pressing the Q key.
Rapid data transfer    Q
01 - Engine electronics

Note:
 
→ If the display shows one of the messages reproduced here, run through the fault-finding procedure as described in the Fault-Finding Programme for diagnosis wiring.
Rapid data transfer    HELP
Control unit does not answer
 
=> Current Flow Diagrams, Electrical Fault-Finding and Fitting Locations
Rapid data transfer    HELP
Fault in communication build up
 
Rapid data transfer    HELP
K wire not switching to earth
 
Rapid data transfer    HELP
K wire not switching to positive
 
→ The display on fault reader V.A.G 1551 will show the control unit identification code. For example:
8B0906018.. 1.8l    R4S/5V MOTR HS    D..⇒
Coding 05001    WSC 06388

- 8B0906018..

Control unit number (see Parts List)

- 1.8 ltr.

Engine capacity

- R4S/5V

In-line, normally aspirated engine, 4 cylinders,
5 valves per cylinder

- MOTR

Motronic

- HS
AT

HS = manual gearbox
AT = automatic transmission

- GRA (or CCS)

Only appears on vehicles with cruise control system

- D..

Software version in control unit

- Coding 05001

Control unit coding

- WSC 06388

Workshop Code of the V.A.G 1551 with which the last coding was performed

Notes:

  • ◆ Incorrect coding may lead to higher emissions and increased strain on the automatic gearbox resulting from harsh gear-shift jolts.
  • ◆ Incorrect coding also causes non-existent faults to be stored in the fault memory.

If the coding differs from the vehicle version, then:

  • ‒ Check control unit coding
    => Coding engine control unit, Page 01-58
  • ‒ Press ⇒key.
 
→ Indicated on display:
Rapid data transfer    HELP
Select function XX

Note:

Press the HELP key to obtain a printout of the functions which are available.

Interrogating and erasing fault memory > < Technical data for self-diagnosis