2004 Lexus LS 430 Owners Manual - Page 353

STARTING AND DRIVING D The millimeter wave radar sensor automatically detects dirt if it is sticking to the front of the sensor or grille cover of your vehicle, and if detected, a message is shown on the multi-information display. However, if the sensor or grille cover is covered with a metallic vinyl bag, icicle, snowflakes, etc., dirt may not be detected, resulting in improper vehicle-to-vehicle distance. Continue driving with due care to the vehicle ahead. If dirt is detected, the dynamic radar cruise control function is automatically cancelled. Always keep the sensor and grille cover clean. Dynamic radar cruise control should not be used in the following conditions, to avoid serious injury or death. D In bad weather (such as rain, fog, snow, sandstorms, or when raindrops or snowflakes get in the millimeter wave radar sensor or the grille cover), the vehicle-to-vehicle distance will not be measured accurately. If the wipers are operated at high speed (including the high speed operation with the wiper lever in the "AUTO" position), dynamic radar cruise control is automatically cancelled. (In the case of the low speed operation and intermittent wiper operation, it is not cancelled.) Dynamic radar cruise control is automatically cancelled when the measurement is extremely unstable due to bad weather. D On the roads in heavy traffic or at sharp bends: As an appropriate speed cannot be maintained, serious injury or death could result. D On slippery road surfaces (icy or snow-covered road surfaces): The tires will race and you will be unable to control. 333