2003 Lexus ES 300 Owners Manual - Page 135

COMFORT ADJUSTMENT However, this threshold velocity will be considerably higher if the vehicle strikes an object, such as a parked vehicle or sign pole, which can move or deform on impact, or if it is involved in an underride collision (e.g. a collision in which the nose of the vehicle "underrides", or goes under, the bed of a truck, etc.). It is possible that in some collisions at the lower zone of airbag sensor detection and activation, the SRS airbags and seat belt pretensioners will not operate all together. For the safety of all occupants, always wear your seat belts properly. The SRS front airbag system is designed to activate in response to a severe frontal impact within the shaded area between the arrows in the illustration. The SRS front airbags will deploy if the severity of the impact is above the designed threshold level, comparable to an approximate 25 km/h (15 mph) collision when impacting straight into a fixed barrier that does not move or deform. If the severity of the impact is below the above threshold level, the SRS front airbags may not deploy. 121