Circuit/System Verification
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.
DTC C1100 will set as result of power brake booster vacuum sensor or circuit failure, test for power and ground circuits to the EBCM.
- Repair the power or ground circuits.