1998 GMC Sonoma Owner's Manual - Page 164

The anti-lock system can change the brake pressure faster than any driver could. The computer programmed to is make the most of available tire and road conditions. Here's how anti-lock works. Let's say the road is wet. You're driving safely. Suddenly an animal jumps out in front of you. You slam on the brakes. Here's what happens with ABS. You can steer around the obstacle while braking hard. As you brake, your computer keeps receiving updates on wheel speed and controls braking pressure accordingly. A computer senses that wheels are slowing down. If one of the wheels is about to stop rolling,the computer will separately work the brakes at each front wheel and at both rear wheels. 4-8