Test Description

WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

3. This step tests for voltage supplied to the PCM from the EBCM.
9. The PCM may be damaged if the delivered torque signal circuit is shorted to voltage.

Fig 1: DTC C0287, P1644, or P1689 Diagnostic Test (Steps 1-4)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC C0287, P1644, or P1689 Diagnostic Test (Steps 5-12)

Courtesy of GENERAL MOTORS CORP.