Anti-Lock Brake System With Traction Control System - Abs-VI: Operation

During normal driving and braking operations, ABS acts like a conventional braking system. Each wheel speed sensor constantly sends an AC voltage signal to EBCM or EBTCM. This information is translated to wheel rotation speed. When EBCM or EBTCM detects wheel lock-up is about to occur, it activates appropriate solenoid to pulse on and off rapidly, regulating hydraulic pressure to each wheel. A slight pulsation should be felt through brake pedal, indicating ABS is working.

BRAKE warning indicator (Red) will illuminate when ignition switch is turned to START position and should go out when ignition switch is turned to ON position. ABS warning indicator (Amber) and TCS or TRAC OFF/LO TRAC warning indicators (Amber) will illuminate when the ignition is turned on, then go out after approximately 3 seconds. If any indicator remains illuminated more than 30 seconds after vehicle is started, system malfunction is indicated. See DIAGNOSIS & TESTING.

Red BRAKE warning indicator will activate if parking brake is applied or brake fluid is low. Amber ABS warning indicator is controlled by EBCM or EBTCM and comes on if problem is detected with ABS. When indicator is illuminated, ABS is disabled and braking is accomplished by conventional brake system. If both warning indicators are illuminated, check conventional brake system for hydraulic system failure. Amber TCS warning indicator is controlled by EBTCM and comes on if problem is detected with TCS. The amber TRAC OFF warning indicator is controlled by the EBCM and comes on if a problem is detected with the ETS. When these indicators are illuminated, the TCS or ETS is disabled and braking (conventional and ABS) is unaffected.