Test Requirements:

Test requirements:
^ Haldex clutch function OK, checking "Guided Fault Finding".
^ Oil level in Haldex clutch OK, checking Oil level in Haldex clutch, checking.
^ All fuses OK according to wiring diagram (to check, remove fuses from fuse socket).
^ Voltage supply OK (at least 10.0 V)
^ Brake light OK
^ Correct engine control module and ABS control module installed (check coding and control module identification number).

Test steps, overview





Electrical test, performing
- Switch ignition off for all testing steps.
- Raise vehicle.





- Disconnect connector on rear final drive.

Note:
^ The Multimeter V.A.G 1526/A and auxiliary cables from Connector Test Set V.A.G 1594/C are used to test.
^ The correct measuring range must be set on the gauge each time before the measuring lines are connected. Otherwise, electronic components could be destroyed!

Connector terminal assignment





1 - Voltage supply (terminal X)

2 - Ground (terminal 31)

3 - Positive connection terminal 54 (brake light, brake light switch)

4 - Parking Brake Warning Light Switch F9

5 - Diagnostic K-line

6 - Not used

7 - Data BUS connection with engine control module and ABS control module (CAN Low)

8 - Data BUS connection with engine control module and ABS control module (CAN High)

Test step 1
The voltage supply from All-Wheel Drive Control Module J492 is tested.
- Switch on 20 V measuring range.
- Switch on ignition.





- Measure on removed connector between terminal 1 and terminal 2 (ground).

Specified value: Battery voltage

Specified value is not reached: service wire routing according to wiring diagram.

- Switch ignition off.

Test step 2
The Brake Light Switch F function is checked.
- Switch on 20 V measuring range.
- Switch on ignition.





- Measure on removed connector between terminal 3 and terminal 2 (ground).

Specified value: less than 0.5V

- Operate brake pedal.

Specified value: Battery voltage

Specified values are not reached: Service wire routing according to wiring diagram.

Specified values are still not reached: Replace Brake Light Switch F.

Test step 3
The Parking Brake Warning Light Switch F9 function is checked.
- Switch on 20 V measuring range.
- Switch on ignition.





- Measure on removed connector between terminal 4 and terminal 2 (ground).

Specified value: Greater than 6 V

- Activate parking brake.

Specified value: Less than 0.5V

Specified values are not reached: Check wiring routing to instrument cluster (T32a/12) in regard to open circuit or short circuit to positive.

Specified values are still not reached: Check wire from terminal T32/1 (instrument cluster) via fuse no. 11 (5 A) to terminal 15.

If no malfunction was found, Parking Brake Warning Light Switch F9 should be replaced.

Test step 4
The Data BUS wire function is checked.
- Switch on measuring range 20 k Ohms.





- Measure between the following terminals on removed connector.





If specified value is not reached, service wiring routing according to wiring diagram.
- Also check Data BUS wires for open circuit. Wire resistance: max. 1.5