2003 Nissan Altima Owner's Manual - Page 154

WARNING ● While driving on a slippery surface, be careful when braking, accelerating or downshifting. Abrupt braking or accelerating could cause the wheels to skid and result in an accident. ● If the engine is not running or is turned off while driving, the power assist for the brakes will not work. Braking will be harder. heat up the brakes. Do this until the brakes return to normal. Avoid driving the vehicle at high speeds until the brakes function correctly. ANTI-LOCK BRAKE SYSTEM (ABS) (if so equipped) The anti-lock brake system controls the brakes at each wheel so the wheels do not lock when braking abruptly or when braking on slippery surfaces. The system detects the rotation speed at each wheel and varies the brake fluid pressure to prevent each wheel from locking and sliding. By preventing wheel lockup, the system helps the driver maintain steering control and helps to minimize swerving and spinning on slippery surfaces. Parking brake bedding The parking brake shoes must be "bedded down" whenever the stopping effect of the parking brake is weakened or whenever the parking brake shoes and/or drum/rotors are replaced, in order to assure the best brake performance. This procedure is described in the vehicle service manual and can be performed by a NISSAN dealer. When driving, the anti-lock brake system controls the wheels so they will not lock when braking abruptly or when braking on a slippery road. Thus, difficult steering and swerving of the vehicle due to locked wheels is minimized. The system detects the wheel rotation rate and electronically controls the pressure applied to each brake. Slight vibration on the brake pedal accompanied by noise usually occurs while the ABS system is operating. Such vibration and noise encountered during abrupt braking is not a problem, but indicates that the system is functioning properly. However, the pulsation may indicate that road conditions are hazardous and extra care is required while driving. Using the system Depress the brake pedal and hold it down. Self-test feature The anti-lock brake system consists of electronic sensors and hydraulic solenoids controlled by a computer. The computer has a built-in diagnostic feature that tests the system each time you start the engine and move the vehicle at a low speed in forward or reverse. When the self-test occurs, you may hear a ''clunk'' noise and/or feel a pulsation in the brake pedal. This is normal and is not an indication of any malfunction. If the computer senses any malfunction, it switches the anti-lock brake system off and turns on the ABS brake warning light on the instrument panel. The brake system then operates normally, but without antilock assistance. WARNING Do not pump the brake pedal. Doing so may result in increased stopping distances. Wet brakes When the vehicle is washed or driven through water, the brakes may get wet. As a result, your braking distance will be longer and the vehicle may pull to one side during braking. To dry the brakes, drive the vehicle at a safe speed while lightly pressing the brake pedal to Normal operation The anti-lock brake system does not operate at speeds below 3 - 6 MPH (5 - 10 km/h). (The speeds vary according to road conditions.) 5-18 Starting and driving