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:

4. This step tests for voltage supplied to the EBCM from the PCM.
5. This step verifies the EBCM is creating a requested torque signal with a valid Hz frequency.
6. This step verifies the EBCM is creating a requested torque signal with a valid duty cycle.
7. The EBCM may be damaged if the requested torque signal circuit is shorted to voltage.

Fig 1: DTC C0298 or P1571 Diagnostic Test (Steps 1-10)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC C0298 or P1571 Diagnostic Test (Steps 11-12)

Courtesy of GENERAL MOTORS CORP.