The Dreaded Turn Signal Problem
 

I purchased a 1980 911 Targa last summer and have been following the posts for a while. I did a search and could not find the full answer. My right front turn signal/side marker and fog light do not work. The left side and the rears work fine. Checked the ground connections on each light and they look good. I assume the grounds to these three are linked and terminate somewhere. Where do they terminate so I can check that connection?

Thanks!

Looking at the schematics, 73's terminate to the body but 82' - 87 make it toward the battery.

So I can't answer - but I think they are shared with the headlight, so if it's the same for the 80, you might be somewhere in between the headlight and your inoperable lights (assuming headlight works).

Oh yeah - Welcome and post a pic sometime.

Lamont, I would start at the the source. Did you check the actual corner marker housing? The wires can be bad there. Remove the lens, then remove the screws for the housing, gently pull it away from from your bumper, now you can test the light bulb housing to see if it works. If it doesn't our host sells them. The fog light is connected to a fuse, relay, and fog light switch. you say one is working, did you replace the bulb on that side? well, i'm sure you did so again, start at the source, unscrew the fog lamp housing from the valence, check the wiring behind the fog lamp housing cover, it's common for water to get in there, the wires get oxidized and rusty, therefore no current will pass. I hope this helps... BTW, I have the same 911-post some pic's!

Not sure that this is the same problem. I had a similar problem on my 86 targa, and there is a diode in the passenger side circuit. I'm not sure if your year has the same circuit.

The diode is housed in a white or clear square plastic housing. It is located under the dash along the knee pad. I recall it being just under the ignition key or to the left of it. Reach under the knee pad and your find a bundle of wires. One of the wires has the diode housing.

I'm not sure this is the same problem.

http://forums.pelicanparts.com/porsche-911-technical-forum/119790-running-lights-problems.html

Thanks for the information. Delayed response secondary to work. Anyway I forgot to mention that the #10 fuse kept blowing as well. Took the side marker, turn signal, headlamp and fog light apart and checked all of the wires. Since the #10 fuse is for the R-turn signal I reconnected all of the wires to the R-headlamp, side marker and fog light. Turned on the lights and fog lights and now the side marker and fog light worked. Loose connection? Who knows but now I was just left with the turn signal. I carefully checked the wires and connectors. It appeared as though there was a fine crack in the clear cover of the blk/wht wire. I wrapped a small piece of electrical tape around it, reconnected it along with the other wires. Replaced the fuse for the 6th time and it worked! Interesting the coincidence with the side marker and fog light although not linked at all.

I lost the diode on our '86 but it only affected the parking lights.

With the ignition on, the right side parking lights would stay on.