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P1608

P1608

Diagnosis information - CAN

Steering wheel electronics (CAN comfort) control unit, communication

Diagnostic conditions
The steering wheel electronics control unit initially tests internal function sequences after wake-up. If they are OK, all diagnosable outputs are then tested and any faults are stored. Steering wheel electronics control unit wake-up through:

- Event-induced CAN message
- Ignition on

Possible fault causes
- No power supply for steering wheel electronics control unit
- Steering wheel electronics control unit is incorrectly coded
- Short circuit or open circuit in the CAN comfort
- Steering wheel electronics control unit faulty (in most cases the cause is not the steering wheel electronics control unit but incorrect coding.)

Fault effects
- Communication via the CAN comfort is no longer possible.
- No other control units are able to communicate with the steering wheel electronics control unit.

Affected contacts on the steering wheel electronics control unit
Connector [A]:
- 1 ground supply - terminal 31
- 2 power supply - terminal 30
- 8 CAN comfort low
- 9 CAN comfort high
- 13 power supply - terminal 15