1998 Chevrolet Express Van Owner's Manual - Page 170

Anti-Lock Brakes (ABS) Your vehicle has anti-lock brakes (ABS). ABS is an advanced electronic braking system that will help prevent a braking skid. When you start your engine and begin to drive away, your anti-lock brake system will check itself. You may hear a momentary motor or clicking noise while this test is going on. This isnormal. ANTI LOCK United States Canada Here's how anti-lock works. Let's say the road wet. is You're driving safely. Suddenly an animal jumps out in front of you. If there's a problem with the anti-lock brake system, this warning light will stayon. See "Anti-Lock Brake System Warning Light" in the Index. You slam on the brakes. Here's what happens with ABS. A computer senses that wheels are slowing down.If one of the wheels is about to stop rolling, thecomputer will separately work the brakes at each front wheel and at both rear wheels.