A wireless remote control radio-transmits a vehicle height adjusting
signal tagged with a remote control identification code in order to
improve vehicle height adjustment operability in a vehicle such as a
truck. The remote control identification code is pre-registered in a
receiver, which, upon receipt of the vehicle height adjusting signal
tagged with the remote control identification code, takes in the vehicle
height adjusting signal. According to information contained in the
received vehicle height adjusting signal, an air suspension ECU controls
the supply and discharge of compressed air for air springs to adjust the
vehicle height. When an emergency operation switch is operated, the
vehicle height adjusting signal from the wireless remote control is
disabled, and vehicle height adjustment is preferentially made based on a
switching signal from the emergency operation switch.