8-28Drive SystemsAll-Wheel DriveWith this feature, engine power isalways sent to all four wheels. It isfully automatic, and adjusts itself asneeded for road conditions.When using a compact spare tire onan AWD vehicle, the systemautomatically detects the compactspare and disables AWD. To restoreAWD operation and preventexcessive wear on system, replacethe compact spare with a full-size tireas soon as possible. See CompactSpare Tire on page 9-79 for moreinformation.BrakesAntilock Brake System(ABS)This vehicle has the Antilock BrakeSystem (ABS), an advancedelectronic braking system that helpsprevent a braking skid.When the engine is started and thevehicle begins to drive away, ABSchecks itself. A momentary motor orclicking noise might be heard whilethis test is going on, and it mighteven be noticed that the brake pedalmoves a little. This is normal.If there is a problem with ABS, thiswarning light stays on. See AntilockBrake System (ABS) Warning Lighton page 4-25.If driving safely on a wet road and itbecomes necessary to slam on thebrakes and continue braking to avoida sudden obstacle, a computersenses that the wheels are slowingdown. If one of the wheels is about tostop rolling, the computer willseparately work the brakes at eachwheel.ABS can change the brake pressureto each wheel, as required, fasterthan any driver could. This can helpthe driver steer around the obstaclewhile braking hard.As the brakes are applied, thecomputer keeps receiving updateson wheel speed and controls brakingpressure accordingly.srx.book Page 28 Monday, June 8, 2009 8:28 AM
