1999 Lexus LX 470 User Guide 1 - Page 219

STARTING AND DRIVING You may hear a small sound in the engine compartment after the engine is started or the brake pedal is depressed repeatedly. This is a pump pulsating sound of the brake system, and it is not a malfunction. Anti-lock brake system The anti-lock brake system is designed to automatically help prevent lock-up of the wheels during a sudden brake or braking on slippery road surfaces. This assists in providing directional stability and steering performance of the vehicle under these circumstances. The anti-lock brake system becomes operative after the vehicle has accelerated to a speed in excess of approximately 10 km/h (6 mph). It stops operating when the vehicle decelerates to a speed below approximately 5 km/h (3 mph). You may hear a sound in the engine compartment for a few seconds when the engine is started or just after the vehicle is started. This means that the anti-lock brake system is in the self-check mode, and does not indicate a malfunction. Effective way to press the ABS brake pedal: When the anti-lock brake system function is in action, you may feel the brake pedal pulsating and hear a noise. In this situation, to let the anti-lock brake system work for you, just hold the brake pedal down more firmly. Do not pump the brake in a panic stop. Pumping the brake pedal makes the stopping distance longer. The brake pedal pulsation caused by the anti-lock brake system may indicate hazardous road surface conditions. Although the anti-lock brake system assists in providing vehicle control, it is still important to drive with all due care, because the anti-lock brake system cannot overcome the laws of physics that act on your vehicle: D Braking capability is dependent on tire friction with the road surface. 203 CAUTION D Do not pump the brake pedal if the engine stalls. Each push on the pedal uses up your brake fluid pressure reserve. D Even if the power assist is completely lost, the brakes will still work. But you will have to push the pedal hard - much harder than normal. And your braking distance will be longer.