Circuit/System Verification
WARNING: This page is about a different car, the 2013 GMC Yukon XL, 2013 GMC Yukon, 2013 Chevrolet Tahoe, 2013 Chevrolet Suburban, and 2013 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
Key ON, engine OFF. The TCCM runs a 2 second bulb test on all indicators of the TCSCS at key ON.