2009 Chrysler Aspen Owner Manual - Page 298

296 STARTING AND OPERATING WARNING! (Continued) • Be sure the parking brake is fully disengaged before driving, failure to do so can lead to brake failure and an accident. • Never leave children alone in a vehicle. Leaving unattended children in a vehicle is dangerous for a number of reasons. A child or others could be seriously or fatally injured. Don't leave the keys in the ignition. A child could operate power windows, other controls, or move the vehicle. ANTI-LOCK BRAKE SYSTEM The Anti-Lock Brake System (ABS) is designed to aid the driver in maintaining vehicle control under adverse braking conditions. The system operates with a separate computer to modulate hydraulic pressure, to prevent wheel lock-up and help avoid skidding on slippery surfaces. All vehicle wheels and tires must be the same size and type, and tires must be properly inflated, to produce accurate signals for the computer. WARNING! Significant over or under-inflation of tires or mixing sizes of tires or wheels on the vehicle can lead to loss of braking effectiveness. The ABS conducts a low-speed self-test at about 12 mph (20 km/h). If you have your foot lightly on the brake while this test is occurring, you may feel slight pedal movement. The movement can be more apparent on ice and snow. This is normal. The ABS pump motor runs during the self-test at 12 mph (20 km/h) and during an ABS stop. The pump motor makes a low humming noise during operation, which is normal.