Audi Workshop Service and Repair Manuals > A4 Mk1 > Power unit | MPFI Fuel Injection and Ignition System | Self diagnosis, V.A.G Inspection Service | Self-diagnosis of Multi Point Fuel Injection | Connecting vehicle diagnosis, measurement and information system VAS 5051 or fault reader V.A.G 1551 and selecting functions

Interrogating and erasing fault memory > < Safety precautions

MPFI Fuel Injection and Ignition System

Self-diagnosis of Multi Point Fuel Injection

Connecting vehicle diagnosis, measurement and information system VAS 5051 or fault reader V.A.G 1551 and selecting functions

Test requirements:

● Supply voltage of vehicle electrical system OK
● Earth connections at engine, intake manifold and bodywork OK.
● Engine fuses OK

=> "Current Flow Diagrams, Electrical Fault Finding and Fitting Locations" binder

● Fuel-pump relay -J17 OK; checking .



‒ → Open rear ashtray (in centre console) and remove cover for diagnostic connector.

‒ → Connect up vehicle diagnosis, measurement and information system VAS 5051 with diagnostic cable VAS 5051/1. Alternatively, connect fault reader V.A.G 1551 with diagnostic cable V.A.G 1551/3A.

Warning

◆ When driving the vehicle for measurement and test purposes, always secure the vehicle diagnosis, measurement and information system VAS 1551 or fault reader V.A.G 1551 to the rear seat and operate it from there.
◆ Pay attention to the safety precautions => Page 01-1.

Note:

The following describes self-diagnosis using the fault reader V.A.G 1551 only.

When using the vehicle diagnosis, measurement and information system VAS 5051, follow the procedures described in equipment's operating instructions.

→ Indicated on display:

V.A.G - SELF DIAGNOSIS HELP

1 - Rapid data transfer 1)

2 - Flash code output 1)

1) appears alternately

Note:

If the display remains blank:

=> Fault reader operating instructions

Depending on the which function is required => "Available functions" table, Page 01-7:

‒ Switch the ignition on.

‒ Start engine.
‒ Switch on the fault reader printer with the print key. The indicator lamp in the key must light up.
‒ Press key 1 for "Rapid data transfer".

→ Indicated on display:

Rapid data transfer HELP

Enter address word XX

Note:

Address word 00 is used to start the automatic test sequence i.e. interrogation of fault memories of all vehicle systems with self-diagnosis capability in "Rapid data transfer" mode.

‒ Press keys 0 and 1 for address word "Engine electronics" and confirm entry with Q key.

→ Fault reader V.A.G 1551 display will show control unit identification. For example:

4A0907473D 2.6l V6 MPFI D01 ⇒

Coding 00083 WSC 12345

Note:

Control unit identification can be printed out by pressing PRINT key on fault reader V.A.G 1551.

Control unit identification (example)

- 4A0 907 473 D	Part no.; assignment => Parts catalogue
- 2.6l	Engine capacity
- V6	Design of engine (V-engine, 6-cylinder)
- MPFI	Multi point fuel injection and ignition system
- D01	Data status (software status) of control unit
- Coding 00083	Control unit code
- WSC 12345	Workshop Code of V.A.G 1551 with which coding was last performed

‒ Press ⇒key.

→ Indicated on display (function selection):

Rapid data transfer HELP

Select function XX

Notes:

◆ After entering the function "01"for "Interrogating control unit version" and confirming with the Q key, you may display the control unit identification again.

→ Indicated on display:

Rapid data transfer HELP

No reply from control unit

‒ Press HELP key to print out a list of possible fault causes.

Check the wiring of the diagnostics connector:

Rapid data transfer HELP

L-wire not switching to earth

=> "Current Flow Diagrams, Electrical Fault Finding and Fitting Locations" binder

Rapid data transfer HELP

K- wire not switching to positive

→ If this display appears when starting or during the program, faults have occurred and data exchange between fault reader V.A.G 1551 and the engine control unit is no longer possible.

Rapid data transfer ⇒

Communication problem

‒ After rectifying the faults, enter "01" again for address word "Engine electronics" => Page 01-2.

Available functions

Vehicle diagnosis, measurement and information system VAS 5051 or fault reader V.A.G 1551		Ignition on, engine off	Engine idling	Vehicle running	Page
Address words
01	Engine electronics	yes	yes	yes	01-2
00	Automatic test routine	yes	yes	yes	01-4
Functions
01	Interrogating control unit version	yes	yes	yes	01-6
02	Interrogating fault memory	no	yes	yes	01-8
03	Final control diagnosis	yes	no	no	01-39
04	Basic setting	yes	yes	no	01-43
05	Erasing fault memory	yes	yes	yes	01-8
06	End of output	yes	yes	yes	01-10
07	Coding control unit	yes	no	no	01-52
08	Reading measured value block	yes	yes	yes	01-54
10	Adaption	yes	yes	no	01-79

Power unit
MPFI Fuel Injection and Ignition System / Self diagnosis, V.A.G Inspection Service / Self-diagnosis of Multi Point Fuel Injection
Connecting vehicle diagnosis, measurement and information system VAS 5051 or fault reader V.A.G 1551 and selecting functions

Interrogating and erasing fault memory > < Safety precautions

Audi Workshop Service and Repair Manuals

A4 Mk1

Power unit MPFI Fuel Injection and Ignition System / Self diagnosis, V.A.G Inspection Service / Self-diagnosis of Multi Point Fuel Injection Connecting vehicle diagnosis, measurement and information system VAS 5051 or fault reader V.A.G 1551 and selecting functions

Power unit MPFI Fuel Injection and Ignition System / Self diagnosis, V.A.G Inspection Service / Self-diagnosis of Multi Point Fuel Injection Connecting vehicle diagnosis, measurement and information system VAS 5051 or fault reader V.A.G 1551 and selecting functions

Power unit
MPFI Fuel Injection and Ignition System / Self diagnosis, V.A.G Inspection Service / Self-diagnosis of Multi Point Fuel Injection
Connecting vehicle diagnosis, measurement and information system VAS 5051 or fault reader V.A.G 1551 and selecting functions

Power unit
MPFI Fuel Injection and Ignition System / Self diagnosis, V.A.G Inspection Service / Self-diagnosis of Multi Point Fuel Injection
Connecting vehicle diagnosis, measurement and information system VAS 5051 or fault reader V.A.G 1551 and selecting functions