Circuit/System Testing
WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
Verify that stop lamp DTCs are not set as current or history before performing this diagnostic. If stop lamp DTCs are set as current or history, go to lighting for diagnose.
- Ignition OFF, disconnect the harness connector of the TBCM.
- Ignition ON, test for 11 volts or greater between the IGN 1