Litronic Issues - Lights Dipped Down
 

Hey Everyone,

I'm having issues with my Litronic headlights stuck in the most dipped down position. I plugged in my Durametric tool and get the following faults:

1:Engine path left

2:Engine path right

3:Axle-position sensor front

4:Axle-position sensor rear

I have checked the axle position sensors and they are all connected, brackets not broken. I also took out both headlights and confirmed headlight leveling motors are seated in their socket and not broken. According to some of the posts on Renntech in the 986 and 996 forums, I believe the Factory Litronics on these cars are supposed to dip down then back up level to match with the vehicle axle sensor position.

When I turn the key ignition to accessory and flip the headlight switch on, the motors can be heard running and headlight beam position flutters but stays dipped low. It’s almost like either the motors are not getting enough power or the correct signal for adjustment. Or maybe the motors are toast.

Looking at the wiring diagram there appears to be a
headlight level control unit, that the sensors and motors tie into for signal and adjustment. Does anyone know where this little sucker can be found? I’ve removed both headlights, entire frunk carpet and raintray, battery tray covers and can’t find it. They say you can troubleshoot this with a multimeter to check the circuit is not broken somewhere and that this control unit is getting power.

Please Help!

http://jdmspares.pairserver.com/PARTS/7382-001.jpg

https://www.picclickimg.com/d/l400/p...ight-Level.jpg

https://rennlist.com/forums/attachme...-19.26.29.jpeg

Perhaps the units you refer to are inside the headlight housings? Its been a while since I had my lights out, but I seem to remember the motor control linkage inside the housing included a ball & socket arrangement - mine was not snapped together properly and when I fixed that, the headlights started behaving properly.........

Negative. I traced the 4 wires coming out of the headlight leveling motors and they are pinned out to to the headlight main connector plug. I also started tracing the headlight connector that is in the fender but have yet to remove the fender liner or front bumper to see if it’s located there.
I did check under the dash and couldn’t find it. Next steps either remove front fender liners, bumper or remove drivers seat and look where the ECU is to see if it’s there.

Here is the picture of the headlight leveling motor and wiring in the headlight housing. The motor spins on a worm drive screw to retract or push the headlight alignment up or down. This is independent of the allen key adjustment screws that you manually use to make adjustments

https://cimg8.ibsrv.net/gimg/rennlis...316f15f84.jpeg
https://cimg4.ibsrv.net/gimg/rennlis...1d4c9d27f.jpeg
https://cimg1.ibsrv.net/gimg/rennlis...882baec32.jpeg

Its been a while, but that white connecting arm/socket was not fully seated when I re-assembled one of my lights, it looked correct but did not function properly......I went in for a closer look and found I needed to "snap" it back together properly. Once I did that the lights would do their alignment dance at startup.

Since this is happening to both of them that leads me to think about checking the ignition switch itself.

I had this same issue in my 986S (same codes) with litronics and it was that the modules were not plugged all the way in after a bumper R&R (same as what it sounds like T Kono had).

When the adjuster is dangling it won't throw codes they'll just be permanently aimed at the ground. My 996TTs both had the nut come off the adjuster on the control arm and I found the arm dangling.

checked both headlights, the motors are fully seated in their sockets.

Mini update,

Removed the driver’s fender liner, confirmed the headlight wiring harness goes straight into the frunk and follows the main wiring harness through the firewall into the dash.
The headlight level control unit must be located in the interior of the car. Possibly under the steering wheel.

I put everything back together and plugged in the durametric. Activated the motors to in the headlights to max position and the drivers headlight went up a lot and the passenger headlight moved up maybe a 1/3 of the way up compared to the drivers headlight.
Ran the motors to min position and confirmed this is where they are set at currently.
I noticed when you give the command through the durametric for max position. The headlights go up for a few seconds then drop down. Is this normal?

I think im going to order a new passenger headlight motor and maybe remove the axle sensors to see if these can be tested out with a multimeter.

https://cimg5.ibsrv.net/gimg/rennlis...9c16bd2b11.jpg
Found it.. It's under the passenger airbag. (RHD car)

^^ I thought I procrastinated with my projects. lol

Speaking of proscrastination. I'm having a related issue. I refreshed the suspension on my 2002 targa; both level sensors were necessarily disconnected and reconnected mechanically, but I did not mess with the electrical connectors or wires. The battery was disconnected throughout the entire process. Now that everything is back together my litronic headlights no longer dip at startup. I am certain they did before the suspension work. I put my scan tool on the car but did not find any reference to litronics or headlights.

hi there,
I just did the same suspension refresh back in 2020. My issue ended up being one of the sensors was faulty. Since the front and rear drivers side litronic sensor work in tandem with the control unit. They both need to function to allow the lights to modulate up and down. My driver front sensor had been dangling for sometime before I replaced the armature mount on the control arm that senses suspension travel.
I was getting faults on the litronic section of the durametric but it wasn’t specific enough to tell me which sensor. Just the system as a whole.
I took my car to Musante Motorsports here in CT to troubleshoot and they told me try changing one of the 2 sensors and see if it helps. It did

Updating the thread with my results. I purchased a Durametric, hooked it up, checked the module. It showed normal function and no faults. I then used the Durametric's activation functions to move the motors up and down and, lo and behold, they moved up and down. After doing that -- presto, my lights once again dip on startup.

So: there was nothing wrong and now it's fixed. Thanks Porsche! :thumbup:

I just completed a suspension refresh as well and noticed my front sensor is dangling. Thankful for this discussion as I hope to resolve my headlight leveling issue next!

My lights have never dipped and come back up when turned on in the 7 years that I've owned the car, lol. I noticed they were aimed low and manually moved them up. Might need to check out the suspension sensors. I know they are properly hooked up but might need to be replaced. @dcruz90 do you know the part number for the suspension sensors?