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 a voltage signal from the PCM.
4. This step tests for a missing or erratic vehicle speed signal from the PCM. An assistant may be required to perform this test.

Fig 1: DTC C0235-C0237 Or P0609 Diagnostic Test (Steps 1-3)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC C0235-C0237 Or P0609 Diagnostic Test (Steps 4-10)

Courtesy of GENERAL MOTORS CORP.