2014 Buick LaCrosse Owner Manual - Page 209

Driving and Operating 9-31 Drive Systems All-Wheel Drive Vehicles with this feature always send engine power to all four wheels. It is fully automatic, and adjusts itself as needed for road conditions. All-Wheel Drive (AWD) system performance will be automatically reduced when the compact spare tire is in use. To restore full AWD performance, and prevent excessive wear to the AWD system, replace the compact spare tire with a full-size tire as soon as possible. See Compact Spare Tire on page 10-76. Brakes Antilock Brake System (ABS) This vehicle has ABS, an advanced electronic braking system that helps prevent a braking skid. When the vehicle begins to drive away, ABS checks itself. A momentary motor or clicking noise might be heard while this test is going on, and it might even be noticed that the brake pedal moves a little. This is normal. If there is a problem with ABS, this warning light stays on. See Antilock Brake System (ABS) Warning Light on page 5-20. If driving safely on a wet road and it becomes necessary to slam on the brakes and continue braking to avoid a sudden obstacle, a computer senses that the wheels are slowing down. If one of the wheels is about to stop rolling, the computer will separately work the brakes at each wheel. ABS can change the brake pressure to each wheel, as required, faster than any driver could. This can help you steer around the obstacle while braking hard.