Body Computer Module (BCM) Trouble Codes & Input Tests

The vehicle self-diagnostic system includes one BCM trouble code and three BCM input tests which involve the anti-lock brake system.

BCM Code B482, Low Brake Pressure
Code B482 will set if the hydraulic brake pressure input to the BCM (pin 2B1), is held low (at ground), continuously for 50 seconds. This BCM input will be pulled low by the ABS pressure switch in the event of low accumulator pressure. If code B482 sets, the low brake pressure message on the driver information center will be displayed.

BCM Input BI18, Brake Pressure
BCM Input test BI18 can be used to determine the status of the hydraulic brake pressure input at BCM pin 2B1. This input is normally held high (at battery voltage) and is pulled low (grounded), in the case of low brake pressure.

BCM Input BI21, Brake Fluid
BCM input test BI21 can be used to determine the status of the brake fluid level input at BCM pin 1C2. This input is normally held high (at battery voltage) and is pulled low (grounded), by the fluid level sensor in case of low brake fluid.

BCM Input BI22, Park Brake
BCM Input Test BI22 can be used to determine the status of the parking brake pedal switch input at BCM pin 1C5. This input is normally held high (at battery voltage) and is pulled low (grounded), by the parking brake pedal switch whenever the brake is applied.