A4 B7 3.0 TDI Retrofit Tow Hitch - Problems

[3.0 TDI Paul]

I’ve recently installed a tow hitch to my A4 B7 3.0 TDI (2007MY). I’ve followed the instructions however when wiring the changes to the 32 pin grey plug the car’s indicators stop working inside and out, but hazard lights work but no clicking sound can be heard in the car.

The remote key also fails to lock/unlock the car but it can be started and driven.

Reverting the wires in the 32 pin grey plug restores the problem, however the how electric do not work.

Has anyone successfully retrofitted a tow hitch to an A4 B7?

Any tips would be gratefully received.

Paul

[3.0 TDI Paul]

Resolved the issue.

Problem is a mistake in Audi/Westfelia instructions.

Instruction 14: remove orange/green (CAN High), orange/brown (CAN Low) and black/red (power) from 32 pin grey plug. Insert into black 3 pin plug supplied with wiring kit. Ensure orange/green, orange/brown and black/red wires match wires from tow loom.

Instruction 15: this is the mistake!
Take 3 new wires from tow loom and insert back into 32 pin grey plug to replace the 3 removed from previous instruction.
Black/red into chamber 15 as per instructions. Orange/green into 13 NOT 12 as instructed. Orange/brown into 12 NOT 13 as instructed. This is to ensure you do not cross connect the CAN High and Low wires.

Rest of instructions are ok.

Tow electrics work as should finally.