auto leveling head light trouble shooting

[mikeinmn]

Originally Posted by civdiv99

The bmw fault message for most things involving self-level and similar type systems is "$$$$$$$$"

[recklessspyder]

There's a good chance that if you had the car jacked up....the front sensor arm came back down the wrong way. Happened to me twice.

[Clockwork]

hey guys,I took my headlights out to replace the bulbs. I put the lights back in and put them to where they should align with the body pannels but now the lights auto aim kinda high.
Shouldn't the self-leveling system dip them back to where the angle should shine towards the ground, regardless of how the housing sits (to some reasonable degree)?

what I mean is if the beam is supposed to be 1.5° dip from horizontal, then when I put the headlights back in the truck, if I accidently aim the housing a bit too high, shouldnt the motor compensate and still dip them at 1.5° down from horizontal?

[thunderX]

Not from my experience. That angle is set relative to the rear sensors for ride height and front sensor for headlight level. When you removed the headlights, the sensors would not know if you put them back where they were because there is no sensor in the headlights themselves.

All you have to do is either remove/reinstall (which is what I would do) or just re-adjust the headlights using the adjustments closer to the center. The outer adjustments are for left/right.

[civdiv99]

Clockwork,

The lights don't attempt to "level" in the sense you may be thinking about. It's really a relative thing. Level for the headlights has nothing to do with the outside world. Level in this context refers to the relative aiming point with respect to the chassis, which is why they receive inputs from the right side suspension height sensors. The lights are set to a desired aiming point and the system programming takes that relative position as "normal." Now let's say you have a circumstance whereby the normal "even keel" of the X5 is disrupted. The best example of this is if you hook up a trailer to the stock BMW trailer connector (doing so changes how the suspension responds to height changes in substantial ways, but we're not getting into that here). So for example, in that circumstance the lights would adjust to aim according to the original setting - thus if the back is down for some reason, the lights will tip down accordingly - but nothing in the system detects "level" in the sense that we use the term. So slowly winding up a steep roadway does not mean the lights "level" and point what would be down at the road, for example. I think a more accurate way to put this would be to say the lights compensate for changes in the vehicle's stance in an attempt to not blind drivers, and to not shine too low to be safe. If there is not a fault (all bets are off on this explanation if there is a fault in the system), then the system will set the lights to what is "normal" based only on settings the system has has been configured for, be that illuminating the space station, blinding ants, or whatever. With my X5, I can adjust my headlight aiming over a narrow, but useful, range of vertical adjustment. The computer has no way to know if the light is pointing as desired or not. It just adjusts the housing assy relative to the chassis. If you want something different, then just adjust the mechanism - a strictly mechanical adjustment (screw). The system will still correlate the position of the headlight assembly relative to the chassis, compensating for load or whatever, so if you adjust the relative position then that's your new normal.

Civdiv99