SilverSFR

Can anyone tell me if the front (L/R) marker lights are tied into the system that monitors and sets off the tail lamp warning? I am chasing down the problem of why my tail lamp error light keeps comming on.
I have replaced bulbs and cleaned connections and grounds. all lights work.

SilverSFR

John..

Yes, these are tied together and a dirty connector can cause an error. Also, make sure you have all the same type and wattage of bulbs in the sockets. it is probably a dirty connection.

SilverSFR

John, Thanks for the answer. I will call you tonight. I have some questions on your fuel system delivery.

SilverSFR

Big Dave

I was chasing this gremlin for a while.....I found out it was the license plate lights were corroded.

The warnings weren't caused by the tail lights in my case It was caused by the license plate lights. They are frequently pretty nasty and corroded. I managed to clean mine up with a Dremel, but they cost $30 each brand new. Just something else for you to check before you start pulling your hair out.

John Struthers

Big Dave,
I'll be royally P.O.'d if it's my license plate lights after reverse engineering the 928 electricals.
Happy but P.O.'d.

SilverSFR

So, i have replaced ALL light bulbs, cleaned all bulb sockets, and replaced lamp controller$$$. I have also cleaned the connectors at the spare tire well. I am still getting the damn tail lamp ! to come on randomly. I am going to have an aneurism if i cant figure this out. Does anyone have any other suggestions?

SilverSFR

SharkSkin

Do the same with the front running lights. Pretty much any external light(or connection in between), except I think the fog and headlamps, can make this warning come on.

V-Fib

Clean all grounding points, under the steering column, above the fuse/relay panel, both sides in front, the engine ground and of course the ones in the rear. Also, if the bolts are corroded (even slightly) at the grounding points clean them or replace them. This can make a big difference.
Good luck.



Anthony Tate
79/928 Silver Metallic

2ndof2

I only make the same suggestion as one of the guys above from experience. You absolutely MUST have the same light bulbs or the system may detect some imbalance and set off the sensor even if the lights all work. I don't believe the front side markers are tied to the circuit but one of the electrical gurus may be able to tell you for sure. I had a problem with the sensor going off a while back after replacing a rear side marker bulb with a non-Porsche purchased bulb. Apparently it was a different bulb and set off the sensor because it was drawing more energy. Good luck!

SharkSkin

Well, on my 78, the warning didn't go away until I replaced my front side-markers. YMMV.