Defect Code 51

Defect Code 51:

Malfunction: Diagnostic Mode with Control Unit not Possible:

Possible cause: Power supply, ground, RxD/TxD link

Note: Refer to notes in the BMW DIAGNOSTIC SYSTEM Troubleshooting: Is it possible to adjust the seat or mirror from the vehicle?

Yes: Check RXD and TxD link from the diagnostic socket to connector X 648 Pin 5 and 6 and repair if necessary.

No: Go to defect code 46.