P0571

Switch 'Brake light' has a malfunction. There is an invalid signal.


Possible cause:

- S9/1 (Stop lamp switch)
Affected functions:

- Engine diagnosis
- Engine output

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Test 1: Check component S9/1 (Stop lamp switch).

1. Check component S9/1 (Stop lamp switch).
Test sequence

- Switch on ignition.
Status of relevant actual value:
- Stop lamp switch:Warning!
Specified value

- Switch S9/1 (Stop lamp switch) operated:OPERATED
- Switch S9/1 (Stop lamp switch) not operated:NOT OPERATED
The actual value is supplied through CAN bus from component N47-5 (ESP, SPS [PML] and BAS control unit).Question

- Is the actual value o.k.?


YES
The actual value is okay.End of test

NO
The actual value is not o.k.Possible cause and remedy

- Read fault memory from control unit ESP and rectify faults.
End of test