Diagnostic System Check - Lighting Systems
TEST DESCRIPTIONSteps 1-5:
The numbers below refer to the step numbers on the diagnostic table.
2. Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
3. The Lighting Systems Symptoms will determine the correct diagnostic procedure to use when no DTCs are present.
4. The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.
5. DTC B1000 and DTC B1001 are internal BCM malfunctions and should be corrected before performing any other diagnostic procedure.