Xenon auto leveling problem

[Rene_Z4MC]

My Xenon lights suddenly stopped doing that initial up/down cycle during start and they are constantly in the maximum low position pointing downwards. During the up/down cycle there is a humming noise but no motion in either of the headlights.

I've searched the forum and found that this usually caused by a faulty/broken trailing arm level sensor.
I removed both front and back sensors, tested them on the bench (with power supply and multimeter) and they both appear to be fine, 0.5V - 4.5V linear output range when moving the arm.

I'm a bit stuck at the moment, has anybody had this issue before or does any of you have any idea what to check next?

Any advice is welcome.

Cheers,
René

 

[TomK]

Both lights 'failing' at the same time indeed suggests a sensor problem. Are you sure part number 5 here hasn't failed?
http://www.bmminiparts.com/DiagramView.aspx?DiagramId=104371&MOSP=49422
One of mine was not levelling properly once. i checked everything and came to the conclusion the actuator had failed, replaced that with another known good one, no joy, put the old one back in and hey presto, all good go figure!

 

[Rene_Z4MC]

Hi Tom,
Yeah pretty sure the mechanical side is ok, took them both off, checked them and mounted them back, all looked fine but lights remain in the lowest position

 

[TomK]

Well that is odd happy to post you the actuator I have spare to try if that helps.