Checking wiring connection between "white" diagnostic connector and engine control unit — AUDI

ACZ
Note:

This check has to be performed if one of the following displays appears on the connected fault reader V.A.G 1551.

Rapid data transfer
Communication problem
Indicated on display:

or

Rapid data transfer
HELP
K-line not switching to earth

or

Rapid data transfer
HELP
K-wire not switching to positive

or

Rapid data transfer
HELP
L-wire not switching to earth

or

Rapid data transfer
HELP
L-wire not switching to positive

Location of diagnostic connectors and wiring junctions K and L: In relay panel with fuse box in plenum chamber.

Checking K and L wires, vehicles without immobiliser

Switch off ignition.
Disconnect all other wires for vehicle systems with self-diagnosis from wiring junctions K and L.
Determine which is the K lead for the engine control unit and connect it to wiring junction K.

Notes:

If differently coloured wires are connected to wiring junction K, determine the colour assignments.

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

If wires of the same colour are connected to wiring junction K, determine wire assignment using test box V.A.G 1598 A (resistance measurement).

Start engine, allow to run at idling speed and re-enter address word 01 for "Engine electronics" => Page
01-3
.

4A0907473D
2.6l
V6
MPFI
D01
⇒
Code 00062
WSC 12345
If the control unit identification of the engine control unit appears in the fault reader V.A.G 1551 display:

The fault lies in another system with self-diagnosis capability.

Determine which other systems are capable of self-diagnosis, connect each one to wiring junction K in turn and test.

If control unit identification is still not displayed:

Remove engine control unit and put it into service position => Page
24-14
.
With the ignition switched off, use adapter V.A.G 1598/11 to connect test box V.A.G 1598 A to connector B only of engine control unit (control unit remains disconnected) => Page
24-10
.

Check for open circuit and short to earth/positive or earth in the following wiring connections:

White diagnosisconnector / contact · Wiring junction · Test box V.A.G 1598 A / socket
2 · K · 26
1 · L · 25

Rectify any open/short circuit as necessary.

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

Note:

Proceed in the same way to test the L wire.

Checking K and L wires in vehicles with immobiliser

The wiring between the white diagnostic connector and the engine control unit is routed via junction K in the relay carrier with fuse box and the immobiliser control unit.

Wiring junction · White diagnostic connector · Immobiliser control unit · Engine control unit
contact · IN · OUT · contact
K · 2 · 10 · 9 · B6
L · 1 · - · - · B5

Switch on ignition, press keys 2 and 5 for "Immobiliser" address word and confirm entry with Q key.

8D0953234 IMMO AUZ9Z0R4010830 D66
Code 00000
WSC 00000
If immobiliser control unit identification is displayed on connected fault reader V.A.G 1551:

Continue with check A => Page
01-97
.

If immobiliser control unit identification is not displayed:

Continue with check B => Page
01-98
.

Check A

Test the immobiliser control unit and the wiring connections as follows:
Switch off ignition.
Pull connector off immobiliser control unit -J362.

=> Repair electrical system; Repair group 96; Repairing immobiliser; Removing and installing immobiliser control unit
Repair electrical system
Repairing immobiliser
Removing and installing immobiliser control unit

Use cable link to jumper contacts 9 and 10 in connector.
Switch on ignition, press keys 0 and 1 for address word "Engine electronics" and confirm entry with Q key.

If engine control unit identification is displayed:

Renew immobiliser control unit.

If engine control unit identification is not displayed:

Use current flow diagram to check wiring between immobiliser control unit -J362 and engine control unit for open circuit or short to earth/positive.

Check B

Switch off ignition.

Note:

All the diagnostic wiring of the various systems come together in wiring junction K. A defective line (short to earth or positive) or a defective control unit may also lead to one of the fault messages mentioned.

Disconnect all other wires for vehicle systems with self-diagnosis from wiring junctions K and L.
Determine which is the K lead for the immobiliser -J362 and the engine control unit and connect it to wiring junction K.
Switch ignition on and re-enter address word 25 for "Immobiliser".

8D0953234 IMMO AUZ9Z0R4010830 D66
Code 00000
WSC 00000
If immobiliser control unit identification is displayed on connected fault reader V.A.G 1551:

The fault lies in another system with self-diagnosis capability.

Determine which other systems are capable of self-diagnosis, connect each one to wiring junction K in turn and test.

If immobiliser control unit identification is not displayed:

Pull connector off immobiliser control unit -J362.

=> Repair electrical system; Repair group 96; Repairing immobiliser; Removing and installing immobiliser control unit
Repair electrical system
Repairing immobiliser
Removing and installing immobiliser control unit

Test the wiring connections between contact 10 of the immobiliser control unit connector and wiring junction K for open circuit or short circuit to earth or positive using the current flow diagram.
Rectify any open/short circuit as necessary.

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

Replace immobiliser control unit if neither an open circuit nor a short circuit is found.