Dealer installed Litronic headlights now won't motor up

[Fly-n-Low]

I installed Porsche Litronic kit headlights a few years ago in my 2002 Boxster S and they have worked great until recently. They normally go on and 'motor up' to proper position when turned on and 'motor up' again when changing to brights and turn on the bright beam halogen bulbs as well. NOW: They turn on (Sometimes it takes few clicks of the headlight switch to turn them on) but they just sit there aimed about 20 feet ahead. They do not motor up to normal position. When I turn on brights the halogens light up but the headlight do not motor up. I had it at my dealer (Bert Smith Porsche, St. Petersburg FL) for other work and discussed it wit them but they are not familiar with the DIY Litronics. They could I only tell me what I already knew… That they are not self leveling and cannot be tested on the PST2 (or whatever) diagnostic.

Has anyone else experienced this problem and any suggestions on how I fix? Thank you!

[Loren]

:welcome:

When you did the install did you

1. Replace the 7.5 amp fuses (in A9 and A10) with 15 amp fuses?

2. Install and proper wire in the control module for each headlight?

3. Self leveling would never work on the DIY version since the kit did not include the sensors or wiring.

4. Have you removed the headlight and checked the condition of both the plug (on the back of the headlight) and the socket (on the car) that it plugs into. We've seen a bunch of these with damage from improper alignment when seating the headlight.

5. Also check to see that non of the pins have been pushed out of place.

That ought to be a good start...

[Fly-n-Low]

Thank you for your fast reply, Loren… and thank you for the 'Welcome' !. To answer… Yes, I installed 15 amp fuses and they are not blown (first thing I checked!) Yes, I purchased the proper wiring loom for the install. A few days ago I loosened each headlight just to see if the plugs had come loose, but did not remove/disconnect them. Everything looked normal. Tomorrow I will completely remove both headlights and thoroughly inspect everything.

They have worked perfectly for about 3- 4 years now. I believe they stopped leveling at about the same time the headlight switch became cantankerous. Usually they will go on in one or two tries, but sometimes it takes a few turns of the switch to get them on. Could the headlight switch contribute to the problem?

[Loren]

Yes, the headlight switches do wear out.

Usually the headlight switch is bad when - you flip it back and forth a few times you will see erratic behavior.

[JFP in PA]

Also check that the headlight harness plugs are properly seated, and check the grounds as well.

[Fly-n-Low]

Thanks for input. O.K here's the update… Original installation instructions in hand I removed the headlights, spare tire, trunk lining, etc. and inspected every plug, receptacle and wire. All O.K. I checked continuity and that power circuits with a digital multimeter. All O.K. I removed the plug from the headlight control unit, tested the pins and determined it was receiving power from the two sources as it should be and the ground was good. While the headlight control unit was disconnected I turned on the lights and lo and behold the low (HID) and high beams worked as before but the motors did not. Thus I concluded the control unit controls the motors/leveling… not illumination. So now I assume I have a bad control unit. The part number on it is 996.618.151.15. Checked prices for a new one and about fainted. $575.00 on average. eBay has numerous used units from cars with factory installed Litronics for as little as $25.00! The units looked identical but had a slightly different part number: 986.618.051.10. Hmmmm. Would one work? I ordered one from salvage guy in N.M. and when it arrives I will try it out and we shall see. Stay tuned.

[Loren]

996.618.151.15 was the only control unit used on on all Litronic and Bi-Xenon lights in the 986 and 996 series.

​Not sure about the eBay part number - it comes up as not valid.

The salvage route ought to work.

[thom4782]

Perhaps you have a bad leveling sensor or the plug / wiring to one of them is broken. Is fo, the car might think it's tilted. I had an independent reinstall a sensor backwards and the lights would not move up or down.

PS: If you have a durametric cable, you can 1) get the fault code and 2) activate the lights into the up/level/down positions. If they move, then, I say its a sensor.

Edited December 11, 2013 by thom4782

[JFP in PA]

Perhaps you have a bad leveling sensor or the plug / wiring to one of them is broken. Is fo, the car might think it's tilted. I had an independent reinstall a sensor backwards and the lights would not move up or down.

PS: If you have a durametric cable, you can 1) get the fault code and 2) activate the lights into the up/level/down positions. If they move, then, I say its a sensor.

This is a post delivery install, therefore there are no leveling sensors and the Durametric system will not be able to read faults as the lights are not linked to the DME.

[Fly-n-Low]

Thank you for the advice, but JFP in PA is correct. Post delivery (dealer or owner installed) Litronic's do not have sensors for auto leveling. They do however have leveling motors and level to the pre-adjusted setting for low beam and rise a degree or two when the brights are turned on. I am still thinking it is the headlight control. It is very unlikely both leveling motors would die at the same time. The used replacement control I purchased should be here in a few days and I will install it and post the results on the forum, since i cannot be the only one with post delivery Litronic's!

[Fly-n-Low]

Well, I received the used Litronic headlight control ($30.00 from Quality Porsche Parts, Albuquerque NM - from a 2002 Carrera, 47K miles, factory Litronoic) promptly installed it and tested the lights… No change! They still don't motor up, turning low or high beams. The control has a yellow sticker on it with the number 996.618.051.10, but under the sticker is the part number 996.618.151.15, just like my old one.

I've pretty much hit a wall here. I inspected and tested everything I know how to and found nothing amiss. I now have a very expensive 'daytime only' car. On the bright side at least I didn't spend $575.00 for a new control! Any thoughts out there? Has anyone else had this problem? Does anyone know about a wiring diagram or trouble shooting info for the post-sale Litronic kit? Thank you, one & all!

[Loren]

The is a Porsche 6 page TSB on the install - that your dealer should have followed.

[JFP in PA]

I would also go back to what I said earlier; check every plug connection on both lights, try unplugging and reconnecting each of them (making sure they are fully seated) as well as checking the system grounds. A lot of Litronics "bugs" have ultimately be traced to poor system connections which the system does not respond well to at all. Pulling and checking everything is tedious, but often very rewarding.

[Fly-n-Low]

Thanks Loren, I have the TSB and followed it when I did the install a few years ago. I also consulted the Pelican install which is basically the same. The system worked perfect for years until one night I turned on the headlights only see them shine ten feet in front of the car! They did not motor up to normal position. The high beam would not motor up either so even with the high beams on I can't see more than twenty feet. Both headlights failed simultaneously. I re-consulted both aforementioned instructions while troubleshooting but to no avail.

I think what I need to do now is pull the headlights and bench test them. If the leveling motors work then I can test each wire in the loom for continuity, etc. I find it hard to fathom that both motors would fail simultaneously. I suppose the salvage yard controller could also be bad but that would be one heck of a coincidence. What concerns me most is that no one else has responded with experiencing a similar problem, which may mean that the anomaly is limited to my car, thus may be very difficult to diagnose or repair. Good thing I love a challenge :thumbup:

[JuncoJones]

Fly-n-Low,

The Boxster-S has 2 position sensors on the driver's front and rear wheels (also on passenger's?). These potentiometers have a plastic bracket attached to the wishbone. If the plastic bracket is broken, the potentiometer link will be simply hanging, giving a value of 0 or 100, therefore fooling the Litronic system at startup. I replaced the $6 plastic bracket and my Litronic system now runs like a charm!

Sensor link support 996-341-371-03

Julian

[Fly-n-Low]

Hi Julian,

Thanks for the input, but my Litronic system is post-sale - dealer or owner install kit from Porsche. It does not have the sensors on the suspension. I have now tried three control modules and none will work. I purchased two used headlight stepper motors but am not sure how to remove the old ones.. Two screws (easy part) but how to disengage the 'ball' end? Help!

Kelly

[Fly-n-Low]

If anyone is still following this, please note that I found the problem and the headlights are now working perfectly. As a last resort I purchased two used stepper motors on eBay. I replaced the motor on the left headlight and tested it and voila! Both headlights operated properly. Lesson learned…When one stepper motor dies the other one won't work either! I initially discounted the headlight motors because I thought it improbable both would fail simultaneously. Also, diagnosis seemed to indicate a faulty controller. After trying two used controllers with no joy the only thing left was the motors.

As Sherlock Holmes said… When you have eliminated the impossible, whatever remains, however improbable, must be the truth.

A big 'Thank You' to all who tried to help!