944Keith

I’m about the pull my hair out (and I don’t have much left). I own a 1986 944 NA Auto that I’m bringing back from the dead. One issue that just started is my driver’s side tail lights and side markers have quit working. I’ve checked bulbs and fuses and nothing’s blown. I’m a novice at these repairs, but I’m learning. I’ve checked the tail light housing and there’s no corrosion. I have a feeling it’s a ground issue, but I have no idea on my next step. Has anyone had this problem before and how should I proceed to track this issue down?

Autobreza

Had a similar issues, but affected some lights. I had been in the dash earlier and forgot to reconnect the emergency light switch. Worth a look if you've been in the dash recently.

TBarrow

See if this helps find the ground areas...

944Keith

It does help. Thank you. I’ve also been told to check the wiring under the fuse box to see if it’s a loose wire. I have cleaned and checked the MP IV ground, but that didn’t fix the problem.

djantlive

I had a similar issue where all the side markers and taillights were out. It happened after the bumper was taken off.

I ended up taking it to a shop. They pulled a new wire to the front side marker. Sometimes that’s what you have to do I guess

944Keith

Here’s the latest twist to this puzzle. If I use the turn signal while the engine is off and the headlights off, the side lights come on. As soon as I turn the ignition and turn on the headlights, they go dark on the left side. Could this possibly have something to do with the headlight switch?

Tiger03447

Nope. try turning the steering wheel a bit to the right and left. Sounds like you might have a dirty turn signal switch or it's gone bad.

944Keith

I’ll give it a shot. The turn signal switch is new. I had to replace it about a year ago and everything worked fine for a period of months. I don’t understand what can be causing the lights to go out when the ignition is on, but have them work when the ignition is off.

944Keith

Doesn’t seem to be the turn signal switch. I’m leaning toward the headlight switch. May get one and try that out. Anyone got any other thoughts?

daz8161

I have this exact same issue. Did you ever find a solution to your problem?

Petza914

How about the turn signal relay? Also, you don't have led bulbs installed anywhere, do you?

daz8161

Ill have to check the relay but no leds fitted on the external lights, just a couple internally by previous owner but the lights were working fine when I bought the car from him.

orig944

Headlight switch, specifically the contact in the headlight switch that sends power to the side that is not working. The parking light function is powered through the ignition switch, and appears to be working.

944Keith

I did. It was the headlight switch. When it was removed, it literally fell apart. When it was replaced, all the lights worked.

daz8161

Just to follow up mine was also a dodgey headlight switch. Replaced it and all working fine now.