Circuit/System Verification

WARNING: This page is about a different car, the 2009 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.

With a scan tool, command the stop lamps ON and OFF. The stop lamps should turn ON and OFF when changing between the commanded states.

If the stop lamps do not illuminate when commanded, refer to Stop Lamps Malfunction .

Verify that DTC P0572 or P0572 is not set as current.
- If the DTC is set as current, refer to DTC P0572 or P0573
Road test the vehicle and attempt to engage cruise. Verify that cruise control engages properly and the DTC P0571 is not set.
- If DTC P0571 sets as current, replace the ECM.