Caution for Automatic Headlight Leveling with Adjusted Ride Height

Japanese vehicles with HID headlights (high-intensity discharge, also known as Xenon) must have automatic headlight leveling by law since 2006. This mechanism adjusts the headlights' aim to ride height changes from passenger and luggage load, which are detected by sensors on the suspension arms (Photo 1).

Now when you lower your ride height using shock absorbers or low down springs, this can be misread as the car tilting backwards. In that case the headlight beam drastically lowers, diminishing nighttime visibility, and you will need to reset auto-leveling and adjust the beam. For details please consult your car dealer or manufacturer, etc. Vehicles either have both a front and rear sensor, or only a rear one; this happens especially if there is only a rear sensor.

The headlights must always be realigned when lowering ride height, because also without the automatic leveling feature the light beam will shift.