Headlamp Leveling

In certain markets where required, a headlamp leveling system is provided on the vehicle. The headlamp leveling system includes unique front lamp units each equipped with a headlamp leveling actuator motor, and a rocker-actuated headlamp leveling switch integral to the switch pod in the instrument panel center stack. The headlamp leveling system allows the headlamp beams to be adjusted to one of four vertical positions to compensate for changes in inclination caused by the loading of the vehicle suspension. The leveling motors are mechanically connected through an integral pushrod to the adjustable headlamp reflector.

Each time the headlamp leveling switch is depressed the circuitry of the switch pod provides an electronic select status up  or select status down  message input to the EMIC over the LIN data bus. The EMIC then sends the appropriate electronic select request up  or select request down  messages to the TIPM over the CAN data bus. The TIPM responds to these messages by providing a voltage output to the headlamp leveling motors through high side drivers on the headlamp leveling motor right and left signal circuits to move the headlamp reflectors to the selected position based upon the voltage input received from the TIPM. The TIPM also sends the appropriate electronic messages back to the EMIC and the EMIC relays the message back to the switch to control the illumination of the 1  , 2  , or 3  Light Emitting Diode (LED) selected position indicator in the leveling switch button. The EMIC and TIPM logic will only allow the headlamp leveling system to operate while the ignition switch is in the ON position and the exterior lighting is turned ON.