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P1628

P1628

Diagnosis information - CAN

Communication, transmission control unit


NOTE: Internal function test completed.

Diagnostic conditions
The transmission 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.
Transmission control unit wake-up through:

- Event-controlled CAN message
- Ignition on

Possible fault causes
- No power supply for transmission control unit
- Transmission control unit is incorrectly coded
- Short circuit or open circuit of CAN Drive
- Transmission control unit faulty (in most cases the cause is not the transmission control unit but incorrect coding.)
- DME control unit faulty

Fault effects
- No communication can take place via CAN Drive
- No other control units are able to communicate with the transmission control unit.