![]() |
|
|
|
Registered
Join Date: Jul 2024
Posts: 19
|
‘88 Turn Signals
So I’ve had this car, new to me, for about a year. ‘88 911. I know it has a couple other wiring related bugs to work out but are all small, I think. Such as the blaupunkt radio is wired constant instead of to the key so I have to power it down or remove the faceplate everytime I turn the car off (I just unhooked the wiring harness going into it for now). Radio is the least of my worries.
The headlights at first I thought only had high beam then I realized that the dimmer was just very very touchy and had to have slight pressure pulling on it and the low beams worked fine. Read through a bunch of stuff on here about all that and replaced the stalk dimmer switch with hopes that would also take care of the turn signal issue, and it did not. I also replaced the turn signal relay behind the speedo, also did not cure the issue. I used an amp meter at the relay socket and am getting over 12v constant in 2 sockets. Also noticed that the relay socket has 4 terminals and the relay only has 3, is that common on the ‘88 model year or am I using the wrong relay? When I was replacing the stalk dimmer I did notice two things that I’m not exactly sure what are that need to be corrected. -one is this little push switch that has been crimped in. It was tucked up under the dash and pulled down when I was unhooking everyone else. -second is the solid brown wire behind the steering wheel has had the terminal end pulled off and hasn’t been connected to anything in some time, what is this wire? Looks like it could be a ground and just goes to the steering column trim screws? -third I don’t think is an issue but want to be sure since I’m new to these cars, on the headlight switch itself I noticed two terminals that just have a single wire but I believe they are just power and ground and do not get anything on the second terminals. Taking any ideas or clues as to how to correct these turn signals! The indicator bulbs on the dash also do not come on when the switch is flipped for signals. I’m sure it’s something simple but I’ve covered all the basics |
||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
![]() ![]() ![]() ![]() ![]() |
||
![]() |
|
'87 Targa
Join Date: Oct 2003
Location: SanFrancisco Peninsula
Posts: 279
|
I think the brown ground wire in the steering column is for the horn contact ring. Do you know if your horn works?
That's the most trivial of your questions. Sorry I don't have current info on the others. edit: I just looked at mine, and the wire to the horn pad is black. So, maybe I'm incorrect about the horn idea (?). Last edited by WMichelsen; 06-21-2025 at 10:12 AM.. |
||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
There is a brown striped wire that plugs into horn contact that does work yes, this wire is solid brown and was hanging to the lower side of the steering column like it went to the same place as the horn contact but in the bottom side instead of top, which is what made me think it could be a ground wire but the horn works so it really doesn’t make sense haha car has been fairly modified which makes it harder to work on and trace things. It does have aftermarket steering wheel, can tell the dimmer switch had already at some point been replaced, can tell the signal relay socket had been hot and somewhat melted at some point which is why I checked to see if it even had current, does have different bumpers and fog lights which would have led to wiring modifications but it just seems like the turn signals aren’t even getting signal from the switch since no voltage changes anywhere even at the relay socket nor do the dash indicator lights come on for left or right turn signal. I’ve read about trying the emergency flashers to narrow things down, unfortunately the best I can tell my car is not equip with emergency flashers. I don’t see a switch for that anywhere relevant to what I’ve been able to find by researching where it should be located in the car
|
||
![]() |
|
Registered
|
The brown stripped wire is missing a ring terminal that is to go under the lower right screw when you put things back in place.
|
||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
Few more pictures to show the instrument cluster and dash area, no emergency/hazard flasher button that I can find, where it should be that I’m aware of.
The push button switch that was tucked up under the dash has grey wires going to it. And the brown stripe wire behind the wheel went to the horn ring, the solid brown is the one with the end torn off. Still goes to the lower right screw of the column itself? ![]() ![]() ![]() ![]() |
||
![]() |
|
![]() |
'87 Targa
Join Date: Oct 2003
Location: SanFrancisco Peninsula
Posts: 279
|
On my '87, the hazard is in the top-left of the console.
It seems your '88 is missing that, and the rear defrost switch (if you had one). ![]() |
||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
That’s interesting, maybe I need to trace some wires and see if anything is tucked under the dash around that area that I could do something with, or buy the manual for the car and trace all the turn signal wiring outside of what I’ve already checked. Thanks for that, everything Id read showed that hazard flasher button being on the dash by the key switch, that helps seeing that it was probably by the shifter
|
||
![]() |
|
Registered
Join Date: Oct 2022
Location: CT, USA
Posts: 149
|
Quote:
Quote:
Quote:
1 - do the hazards work? (not sure if they’re intact based on the thread) 2 - with the key out, what happens when you use the indicator switch? The hazards are a good test for the system bc they bypass that pesky column switch but use the rest of the same wiring. With the key out or off, the parking lamp filaments should just turn on and stay on. That tests half of the switch (its why your turn signals don't blink from bright to off, they go bright to dim) I wrote about my own turn signal t-shooting, which might be helpful (or not) https://www.joepampel.com/post/turn-signal-issues-electrical-intro If you have the Bentley manual, that diagram is pretty easy to follow. This one is harder to follow, but has the whole enchilda with wire colors and connector pins.. ![]() |
|||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
Haven’t got to try everything, but did rule out the headlight switch and stalk switch both so I put the column back together. I did crimp the terminal end back on the solid brown wire and put to the column itself which is where it looked like it went. It came from the wiper switch.
Main reason for touching base on here again was when I put it together and called it a day, turned everything off I noticed the rear running lights were still on even though the headlight switch was off. Then I realized I still had it “up” which would be right hand turn signal, pushed it back to the middle selection which would be no turn signal and the rear running lights when out. Push it down (left turn signal) no lights, pull it back up (right turn signal) all the rear running lights come back on. Push it to center, everything off, pull the light switch on for running lights and everything comes on as it should. After finding that, I believe that it’s a wiring issue with the rest of the harness past the switches, fuses, relays themselves. Am I wrong with this thought? Since RH signal turns the rear running lights on whether the lights are on, car running, or not? |
||
![]() |
|
Registered
Join Date: Oct 2022
Location: CT, USA
Posts: 149
|
Any difference in behavior if the low beams are on at the same time?
|
||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
No change with hi/lo selector in different location. Messed with it briefly today thinking I may had found the issue but still no change as of yet. Thought last night that hey, maybe it just has the wrong bulbs in everything from when the conversion was done and still just had the single contact bulbs in everything. That was wishful thinking, before even looking I just decided to go ahead to the parts store and buy new replacement bulbs for everything. I got the correct OEM type dual contact 7528’s, it already had 1057s in it but with the voltage difference I thought it would be worth a try. Also put new 7506’s in the reverse light sockets since the reverse lights have also never worked. I haven’t even started that battle as it could just be the switch and would rather have turn signals that I need a lot worse. I did notice that when I was changing out bulbs though that the left front reflector housing isn’t correct for having turn signals. It’s still a single contact housing instead of a dual. The right front housing is the correct dual contact, just not the left front. Ordered new front running light/ turn signal housings to change them both out at the same time so they have the same appearance. If that doesn’t get it then I’m going to chase the harness from the reflector housings back into the rest of the harness but kinda wishful thinking that the way these things work on these cars that once I change the reflector housing out to take the dual contact socket bulb that they will take right off (probably not)
|
||
![]() |
|
Registered
Join Date: Oct 2022
Location: CT, USA
Posts: 149
|
the indicator & parking lamp wiring runs through the headlight buckets and if the bulbs are wrong or someone flipped the 2 filaments or flipped the grounds on the housings… lots of room for mistakes if this had any bodywork in the past. The downside is the front bumper needs to come off to get to the passenger side housings. The reinforcement that protects the oil cooler is in the way. (if you have it that is)
__________________
1988 3.2 Carrera sunroof coupe “Rufus” (as in Parnelli Jones) 1974 Triumph Spitfire “The beast” 1974 VW Super Beetle Convertible “Zippy” 2014 Audi A5 S-line 6-sp “Lyle” |
||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
Yes it’s an ‘88 and has had RSR style bumpers installed at some point. Nice car, but several small bugs that I’m chasing out to get it where it needs to be. I’m going to spend some time with the test light in the coming days and see what I can figure out. If it gets too involved I may very well end up getting the sierra breakout kit and bypassing all of this but everything I’ve done so far needed done regardless.
|
||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
Just about out of time for today, just updating this incase anyone is following and waiting for more info before chiming in. I have been able to get the radio staying live taken care of, as well as the reverse lights. Reverse lights I don’t know what I done honestly other than possibly a loose connection. Changed the bulbs yesterday and they still didn’t work, read up on it last night about jumping the terminals on the 14 pin connector to check the rest of the system to narrow down a bad switch. They worked by jumping terminals. Messed with everything else for a bit, chatted with pelican parts on the phone about the turn signal relay, he had me checking a few things and I noticed that the reverse lights do in fact work, I didn’t do anything other than disconnect the 14 pin connector, jump terminals, and put back together so it had to be a loose connection I assume or they just needed woke up (haha). So back to the turn signals. The main issue. At the fuse box, fuse 9 & 10. They show basically nothing with a multimeter. 0.02, that is with the headlight switch off, on, turn signals off, left, right, nothing. As mentioned previously, I do not have a hazard button, it’s a stripped down car inside. Pelican recommended taking the light switch back out of the dash and checking all the connection to verify everything was hooked up correctly. That’s when I was referencing off the wiring diagram and noticed that the black/green/ white-dashed wire connection for the stalk switch. I took my jumper wire and went from the 12v of the headlight switch and jumped it into the black/green/ white-dashed wire and the hazards themselves didn’t come on obviously but at that point I was able to take the stalk selector switch to left, right, and off and the correct corresponding light would come on solid both on the corner of the car and the tach both. Pelican did say with my car being an ‘88 and having a 4 prong turn signal relay socket that I have the incorrect relay and purchased the correct relay. Thinking somewhere inside the car there is an incorrect wire connection or something just not hooked up at all. Small progress but it is getting narrowed down. I have to call it quits for the day, so if anyone has an advise on where to start checking tomorrow, that would be great, otherwise I’m just going to dive back in blind and see what I can come up with. From what I’ve read also the only two wires required for turn signals to work properly are circuits 15 and 49, which do run through the hazard switch, from what I’ve seen, so I’m going to specifically look for a loose red/white which goes to turn signal relay and red/green wire which is keyed hot, again, you guys all know more than I, but this is all to my understanding reading overly deep on different things that could be involved.
Edit: spent another 30 min or so to chase that grey wire that went to a little push button that was tucked up under the dash I had found when changing out the stalk switch last week. It grounds inside the car under the dash then the other lead goes through the front of the cabin and goes to what used to be the ignition system harness connector. I will add, the car has been converted to MSD and is dual plugged so this harness is no longer plugged in so I will end up pulling that wire and button completely out of the car since it’s not used for anything. I did however find another harness that I’m not sure what went to and many other terminated wires or wires that are on their own and not hooked up to anything currently. ![]() ![]() ![]() ![]() Last edited by InTheDirtCo; 06-24-2025 at 11:55 AM.. |
||
![]() |
|
Registered
|
I guess it’s the norm to have the wiring touched. Over 40 years of tinkering, owners and marginal Stereo Installers. But to start off at the birth of this era of Porsches, is the Spaghetti Bowl at the Sausage Factory. Opps, that reference was for Ferrari. I’ve had cars that had three or so stereos installed and the previous additional wiring was Abandoned In Place. Some 40 feet in one case I recall in a ‘67 Camaro. I guess I and guilty of modifying my wiring with my modes, at least have done it with some grace.
Last edited by porschedude996; 06-25-2025 at 02:10 PM.. |
||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
Haha that couldn’t have been more true and honestly I can’t say anything negative toward all that because that’s the kinda people that keep the car scene alive and active versus the collectors that don’t work on their stuff and sits in a garage without being drove. It doesn’t help that I can’t contact any previous owner because the car was purchased via repo auction. Was sold via ZWECK in Miami to a failed startup business that filed bankruptcy and had their fleet brokered off. I tried contacting ZWECK direct about tracing everything back to a point I had info on the cars original build but they weren’t wanting to mess with it and never returned my call after speaking to someone about it, and I honestly don’t blame them since I’m sure it can get fairly time consuming pulling all the records for a car that was sold close to 10 years ago.
I was able to get the front turn signals working, off the stalk switch as they should. Now the only thing not working is the rear turn signals. The spaghetti under the frunk for the old engine control module, I left alone since it apparently isn’t causing any issues. I do have a few mild upgrades planned for the car 3-5 years out and will weed out all the unused wiring and clean all that up when I cross that bridge in the future and have the car tore down further. Trying to keep it on the road at the moment Last edited by InTheDirtCo; 06-25-2025 at 08:05 AM.. |
||
![]() |
|
Registered
Join Date: Jul 2024
Posts: 19
|
What I ended up doing here, for future reference of anyone else reading this 3+ years from now trying to also diagnose their own turn signal issues. I traced my black/green/white dashed wire that should go to hazard flasher button that had been eliminated, to try finding the rest of the old wiring harness. It was gone, cut, nothing there from when the center console was deleted so there was no power wire feeding the turn signal relay, which meant there was no power going to the signals at all.
I pulled the flasher relay harness behind the dash and used a wire tap to jump in a keyed 12v power source to the 49 line of the flasher relay socket. This supplied power to the flasher relay and gave me signals. When the signals are on I have power at the proper 5a circuits of the fuse box. Everything works as it should again now. I mentioned the front-only working but that is from an issue inside my rear housings that I have yet to diagnose but that’s the simple end of the job and self explanatory compared to how the rest of this process went. I have pulled the pin connector at the back of the car and checked with multimeter and there is indeed turn signal power going from the pin out connector at the rear of the car that powers the light housing on both corners of the car so it’s within my housing for my rear signal issue. I’m saying this job is done in the sense of what brought the issue to the forum which was flat out having no turn signals at all period, not even power at the switch itself or within the fuse box. Thanks everyone for their time in helping me get this issue taken care of |
||
![]() |
|
![]() |