Circuit/System Description
WARNING: This page is about a different car, the 2011 GMC Cab & Chassis Sierra, 2011 Chevrolet Suburban, and 2011 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The instrument panel cluster (IPC) illuminates the antilock brake system (ABS) indicator during the IPC bulb check or when the electronic brake control module (EBCM) detects a fault and sends a serial data message to the IPC commanding the indicator ON.