Brake Warning Indicator

Fig 1: Identifying Hydraulic Brakes System Block Diagram

Courtesy of GENERAL MOTORS COMPANY

The instrument panel cluster (IPC) illuminates the Red Brake Warning indicator when one or more of the following occurs.

• The body control module (BCM) detects that the park brake is engaged.
• The IPC detects a low brake fluid condition. The IPC receives a low brake fluid signal from the low brake fluid switch in the master cylinder reservoir requesting illumination.
• The electronic brake control module (EBCM) detects an ABS malfunction which disables dynamic rear proportioning (DRP). The IPC receives a GMLAN message from the EBCM requesting illumination.
• The IPC performs the bulb check at the start of each ignition cycle. The Red Brake Warning indicator illuminates for approximately 3 seconds before turning OFF.
• The IPC detects a loss of GMLAN communications with the EBCM.