2004 Lexus LS 430 User Guide - Page 390

STARTING AND DRIVING Electronically modulated air suspension control When the pre- collision sensor detects an object or vehicle with which your vehicle may collide, and determines that a collision may be unavoidable, the electronically modulated air suspension adjusts the damping effect on the shock absorbers and regulates the vehicle not to pitch forward so much. The electronically modulated air suspension will operate in the following conditions: D When the ignition switch is turned on. D When the vehicle speed is about 5 km/h (3 mph) or over. D When the approaching speed in regard to the object or the vehicle exceeds about 30 km/h (18 mph). Pre-collision safety failure warning 31L589 If there is a problem somewhere in the pre-collision safety system, the master warning light comes on, a warning tone sounds, and either of the following messages may appear. 372