Test Description

WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. 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 Diagnosis (Steps 1-4)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC C0287, P1644 Or P1689 Diagnosis (Steps 5-12)

Courtesy of GENERAL MOTORS CORP.