2003 Lexus GS 300 Owners Manual - Page 221

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 PAD WEAR LIMIT INDICATORS 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). The brake assist system may not work for about 60 seconds after the engine is started. For an explanation of this system's warning light, see "ABS" warning light on page 47 or 199. 31G017 The brake pad wear limit indicators on your disc brakes give a warning noise when the brake pads are worn to the extent that replacement is required. If you hear a squealing or scraping noise while driving, have the brake pads checked and replaced by your Lexus dealer as soon as possible. Expensive rotor damage can result if the pads are not replaced when needed. 200