Brake Warning Indicator

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2018 GMC Yukon XL, 2018 GMC Yukon, 2018 Chevrolet Tahoe, 2018 Chevrolet Suburban, and 2018 Cadillac Escalade ESV. However, it is still accessible from the selected car via links, so may be relevant.

The instrument cluster turns the brake warning indicator ON when the following occurs:

The instrument cluster performs the bulb check.
The body control module detects that the parking brake is engaged. The instrument cluster receives a serial data message from the body control module requesting illumination.
The electronic brake control module detects a faulty pump motor, solenoid valves, an internal hardware failure or a too high or too low battery voltage and sends a serial data message to the instrument cluster requesting illumination.