2011 Lexus IS 350 Owners Manual - Page 181

2-4. Using other driving systems n Automatic reactivation of the TRAC/VSC systems If the TRAC/VSC systems are turned off, re-starting the engine will automatically reactivate them. n Automatic TRAC reactivation If only the TRAC system is turned off, the TRAC system will turn on when vehicle speed increases. n Automatic TRAC and VSC reactivation If the TRAC and VSC systems are turned off, the systems will not turn on even when vehicle speed increases. n Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC and hill-start assist control systems l A sound may be heard from the engine compartment if the brake pedal is depressed repeatedly when the engine is started or just after the vehicle begins to move. This sound does not indicate that a malfunction has occurred in any of these systems. l Any of the following conditions may occur when the above systems are operat- ing. None of these indicates that a malfunction has occurred Vibrations may be felt through the vehicle body and steering. A motor sound may be heard after the vehicle comes to a stop. The brake pedal may pulsate slightly when the ABS is activated. The brake pedal may move down slightly after the ABS is activated. 188