I had a RX300 with air suspension. This enabled me to have the vehicle lower itself for exiting the car. On entry it would pump up to it's driving position. On one occasion the rear offside unit just kept pumping up until it reached the maximum height. Although I could just drive it with care, the car was unstable. It was the sensor failed but this entailed a replacement unit at a cost of just on a thousand pounds including labour. Be warned.