Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. 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.
2. 5. 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.
3. 6. The presence of either of these codes would indicate an internal module malfunction with the Body Control Module (BCM), inhibiting the operation of the sunroof.
4. 7. The presence of either of these DTCs will inhibit the battery supply voltage to operate the sunroof system.
   Fig 1: Diagnostic System Check - Power Sunroof

   Courtesy of GENERAL MOTORS CORP.