2000 Lexus LS 400 Owners Manual - Page 344

STARTING AND DRIVING Drum-in-disc type parking brake system Your vehicle has a drum-in-disc type parking brake system. This type of brake system needs bedding-down of the brake shoes periodically or whenever the parking brake shoes and/or drums are replaced. Have your Lexus dealer perform the bedding-down. Brake assist system When you slam the brakes on, the brake assist system judges as an emergency stop and provides more powerful braking for a driver who cannot hold down the brake pedal firmly. When you slam the brakes on, more powerful braking will be applied. At this time, you may hear a sound in the engine compartment and feel the vibrations of the brake pedal. This does not indicate a malfunction. The brake assist 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). For an explanation of this system's warning light, see "ABS" warning light on page 68 or 326 and "Vehicle skid control failure warning" on page 318. 327