Load angle sensors
Cars with automatic headlamp levelling are fitted with a front and rear load angle sensor.
The front sensor is fitted between the subframe and the suspension arm and receives information on the wishbone movement in relation to the subframe. This information is sent on to the headlamp/AHL control module as a pulse width modulated signal.
The rear sensor is fitted between the subframe and the lower transverse link and receives information on the movement of the transverse link in relation to the subframe. This information is sent on to the headlamp/AHL control module as a pulse width modulated signal.
The headlamp/AHL control module governs the angle of the headlamps using the information provided by the two load angle sensors.