2005 Lexus LX 470 Owners Manual - Page 304

STARTING AND DRIVING ACTIVE TRACTION CONTROL SYSTEM You may hear a sound in the engine compartment for a few seconds when the engine is started or just after the vehicle begins to move. This means that the active traction control system is in the self-check mode, and does not indicate malfunction. When the active traction control system is operating, you may feel vibration or hear noise of your vehicle, caused by operation of the brakes. This indicates the system is functioning properly. When getting the vehicle out of mud or newly fallen snow, etc., the active traction control system will help operate to prevent the wheels from spinning. 31X518a "Active traction control system indicator light The active traction control system automatically helps control the spinning of 4 wheels which may occur when accelerating on slippery road surfaces, by controlling the output of the brake and engine. Thus, the system assists driver to control the driving power of 4 wheels. When you turn the ignition switch on, the active traction control system always turns on automatically, and the active traction control indicator light will come on. The indicator light will go off after a few seconds. When active traction control is applied, the active traction control system indicator light blinks. 31X503 "Active traction control system failure warning This light warns when there is a problem somewhere in the active traction control system or vehicle stability control system. If the "VSC/TRAC" warning light comes on, have your vehicle checked by your Lexus dealer as soon as possible. 280