Problem with Active Xenon Head Lights
I drove the car tonight, and the drivers headlamp attempts to adjust, but then aims high. The passenger side headlamp does not move, and is aimed about 10 ft. in front of the car. I had to use the fog lamps in order to see the road in front of me.
I looked at the fuse identification chart, but there is no mention of headlamps. Since the leveling of both lamps is affected, it seems that this problem would be an electrical (rather than mechanical) problem.
Does anyone know if there is a module that controls the leveling of the active headlamps, and which fuses or relays protect this circuit?
Thanks very much for your help, as the car is currently not road worthy at night. The drivers side headlamp blinds oncoming traffic, and the passenger side headlamp does not have enough range to adequately illuminate the road.

The fact that the left light tries to adjust but remains aiming high, sounds quite odd. Like the calibration was not correct.
Looks like you have to change some parts anyway, it isn't the control module or only programming or something that simple.
Thank you for your reply! My thoughts about the right head light having a broken stepper motor were exactly the same as yours - at first. We drove the car on a two hour trip just the night before, and the active headlight aiming worked perfectly.
The very next morning is when the active headlamp message appeared. It just seems very odd that two different problems with the head lights would appear at the exact same time, and that they did not have some sort of common cause. I have inspected the wiring and connections on both head lights, and they appear OK.
Could it be possible that the headlamp level control unit (located in the right rear passenger foot well) has become defective?
While the engine was running, and the headlamp switch on, then plugged in the connectors, and the headlamp illuminated, and the projector leveled itself. This test proved to me that the vertical adjustment motor still works.
After shutting down the car and lights, and re-starting, the active headlamp message reappeared, and the projector was again aimed towards the ground.
Tomorrow, I will remove the cables from the battery, let everything rest, and reconnect the cables. Hopefully everything will reboot, and work correctly, but I doubt it.
As always, any help would be absolutely appreciated!
After starting the car, the "active headlamp not available" message was displayed. I then switched off the ignition, turned the light switch from auto to "0" off. I then restarted the car, and no messages were displayed, turned the light switch to "on". The headlamps illuminated, leveled correctly, and no messages appeared.
I then switched the lights and ignition to off, and restarted the car. The "active headlamps not available" message was indeed present, and the right lamp was again aimed low, and the left was aimed high.

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The ESP malfunction indicator did not illuminate after disconnecting the battery. I did not clear any messages, but the active headlamp message was displayed after battery reconnection & startup. It was only when I turned the light switch from "auto" to "off" and restarted the engine that the lights seemed to work correctly, and the message did not appear.
The message has returned with every restart of the engine since, irregardless of the light switch position. The screwy aim also accompanies this message.
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It really sounds odd if both lights failed (at least almost) simultaneously but with a different issue on each. The one aiming high sounds like a calibration issue but how could it have adjusted properly at the test you performed? I cannot see any other option than diagnose the car with Star.
I had my wife start the car with the light switch off while I watched the projectors. The right projector aimed up and down, and side to side with a rather random jerky uncontrolled motion, and finally came to rest. The left projector smoothly moved down, then up, down a little, and stopped.
If the xenon bulb plug on the right is connected, the projector does not move at all. I can unplug the bulb and leveling connectors from the right headlamp, start the car, then plug in the leveling connector, and the projector moves up from its down position, and the bulb plug can then be snapped into place.
WIS indicates that there are projector controllers on the undersides of both headlamps, and a central leveling module in a compartment underneath the passenger side seat. The leveling module receives its input information from the suspension leveling sensors (among others), and makes leveling adjustments accordingly.
Could a failed right projector controller cause the central headlamp leveling module to make an incorrect adjustment to the left side, or would the probability be greater that the central leveling controller has failed, and is incorrectly adjusting both sides? Also, would a failed suspension leveling sensor, or steering angle sensor cause a message to appear in the display?
I know that I am probably in need of STAR SDS assistance for this one, but I like to solve problems by using basic logic troubleshooting as much as possible.
Thanks again for your help!
Last edited by m4coyote; Sep 19, 2009 at 05:13 PM.

But head lights are not controlled separately from the level sensor at each front wheel. You might have a look at the level sensor control unit, possibly the front SAM too if it has water damage.
Any other owner having similar issues, would be very useful to share views.
I will definitely investigate the possibility of damage at the front level sensors.
The issue of water at the front SAM may very well be a possibility. The car was left outside on the night before the headlamps started malfunctioning. That night, we received two inches of rain.
I did pull the fuse box cover, but did not notice any obvious moisture in there. Is it possible that water is in the lower extremities of the box? That would certainly explain why there is a malfunction.

Thanks again guys!
version coded so the error msg no longer displays...
ran testing thru DAS and they all move left/right/up/down fine...
but i cannot tell while driving if the lights are moving sideways or not...
My 2007 came with the cornering bi xenon lights as ordered, and there is no doubt as to whether they move. The movement is a darting, quick motion around/into a corner in response to steering wheel input. It is not slow or imperceptable, but very obvious, with an obvious return to center.
Is it possible your car was built with non cornering headlights?
Last edited by Barry45RPM; Sep 23, 2009 at 05:13 PM.

I was almost arguing with a UK member who had one of the first active cornering lights in his S211, he claimed it is impossible to see the lights moving horizontally while on my 221 and 212 it is easy to see that while driving bending countryside roads. It really should be the same with the 211. Lights may not turn when the car is stationary.
There is a difference with the initial sync too, my cars do not sync horizontally when lights are turned on, just vertically. The early ones seemed to sync in both directions (it depend on a position sensor, some xenons have the position sensor for vertical movement too and those lights do not calibrate at switch on).







