1973 Wiring problems - hazards and lights
 

I am working on my 1973 911 Targa, it's been a ground up restoration. I have all new wire harnesses from Restoration design. that's the good part. I can't figure out what's going on with my lights, blinkers and hazards. I actually have gone backwards

Here is what's going on
Hazards work when the ignition is off or on - standard slow blink of front and rear parking lights

With ignition in the on position
blinker left or right - turns the hazard lights on - fast blinking

with the headlights on, no dash lights blink with hazards or blinkers

Pull the E-brake up and brake warning lights come on dash and hazard lights all blink

I know there has to be a mixed up wire between the headlights, hazards and headlight switch on the column

Any thoughts at what to look at. I have gone back through all my wiring and double check it's correct. I believe it is ..... but it's obviously not

Any suggestions would be appreciated.

anyone have ideas ?

These might help.

https://forums.pelicanparts.com/porsche-911-technical-forum/1154724-71-turn-signal-function.html

http://forums.pelicanparts.com/uploa...1754743060.jpg

http://forums.pelicanparts.com/uploa...1754743166.jpg

thanks, that second diagram is helpful.
I am still struggling to figure out what's going on. Just replaced my hazard button to a new one, thought that was the issue. It's not
Also changed out my blinker switch, that solved my low/hi beam issue but caused others.

Now when I connect my battery my headlights and dash lights come on. Key is off and out of the ignition. I think something to the back of the headlight switch is wired wrong. That's all I can think of.

Any thoughts

Is the harness a copy of the original? Did they supply any wiring diagrams?
Pictures of your terminations at light, ignition switch, etc. might help to see if it matches original.
http://forums.pelicanparts.com/uploa...1754747261.JPG
http://forums.pelicanparts.com/uploa...1754747261.JPG

It's a new wire harness from Restoration Design for my car. I have been talking to the tech guy at RD but we are yet to figure out what's going on. I think it's my connections at the back of the light or hazard. Let me take a few pictures and post them. I do have wiring diagrams but not for the back of the light switch

http://forums.pelicanparts.com/uploa...1754751093.png
http://forums.pelicanparts.com/uploa...1754751107.png
http://forums.pelicanparts.com/uploa...1754751120.png

Here are pics of my wiring behind the lights

http://forums.pelicanparts.com/uploa...1754751183.png
http://forums.pelicanparts.com/uploa...1754751330.png


and pics of the Hazard switch wiring

Some of the main problems come from improper grounds. Make sure the ground wires in the front fenders are clean, and the rear tail light housings.
The connections at the parking brake handle can be a bit difficult. I don't have any good pictures of that. On thing to look at while your in there is to make sure the hand throttle linkage is in good shape.

http://forums.pelicanparts.com/uploa...1754751469.JPG

http://forums.pelicanparts.com/uploa...1754750178.jpg

Bad connections in the light sockets cause issues also. Other threads that might help.
https://forums.pelicanparts.com/porsche-911-technical-forum/1162260-wiring-questions-76-911-a.html

https://forums.pelicanparts.com/porsche-911-technical-forum/1162788-1971-porsche-911-wiring.html

https://forums.pelicanparts.com/porsche-911-technical-forum/1161364-front-turn-signals-out-73-911-a.html

Yeah, I am checking grounds.
That parking break is interesting. When I pull the parking brake up, the red light on the dash comes on as it is supposed. the hazard lights also flash, which is not right. That's why I think something is wired wrong and it's not a ground

http://forums.pelicanparts.com/uploa...1754752092.png

All new fuse panel. Everything is clean.

Here is how I hooked up the lights. Yellow post-it notes are my connections. I found this illustration online.http://forums.pelicanparts.com/uploa...1754754478.jpg

This will be a bit complicated for him to wire. I will send a simple instructions on how to go about it shortly

Your light switch looks right.

Wht/green wire #57 connects to the speedo as an indicator light. It's a green light for headlights or fogs on the front side. When that wht/green is plugged in the light is always on when the key is on. That does not seem correct.

My dash lights are also always on when the key is in the on position. Same if the lights are on or off.

Any thoughts?

I see you have eliminated the drivers battery and installed 2 relays there. I know one should be the horn relay, what is the other?
The Gr/Wh to the speedometer is parking light indicator from the headlight relay. It should only come on when the light switch is pulled to the first section, and go out when pulled out fully for the headlights. Might want to verify the headlight relay is working properly. The tachometer has the high beam indicator.
Do you have the optional fog lights?
Mine has the 2 Wh/Gr shown on the right side in the diagram and the one to the rear fog light in the main harness, but the rest of the harness, relay and switch were options.

http://forums.pelicanparts.com/uploa...1754840140.jpg

http://forums.pelicanparts.com/uploa...1754840226.jpg

Sent PM.

I have three round relays
horn relay (near fuse panel)
fuel pump harness relay (near fuse panel)
control light relay (behind gauges)

One square Hazard relay (behind gauges

I think the Hazard relay is bad or not correct for my car (even thought Pelican says it is)

I do have an option for fogs, I disconnected the wht/green white at the fuse panel, at the gauge and at the lights. Basically deleting that out of the system


http://forums.pelicanparts.com/uploa...1754849542.jpg

ordered two different relays for the Hazard. This relay says E49, the one I order says E24, I also ordered a genuine Porsche relay.

Here is a summary of the issues. You will see why I am thinking it's a relay issue. My headlights and blinkers work fine if I give power at the fuse panel and unhook the dash wiring.

http://forums.pelicanparts.com/uploa...1754850137.jpg

This thread touches on the relay issues.
https://www.early911sregistry.org/forums/showthread.php?171471-1972-911-Flasher-Unit

I looked at some of your past posts. You seem to have a bit of a project car going. I see posts for aftermarket light housings, ignition switch, '76 engine build, and you mention having a fuel pump relay which would not have been used in cars till later '70's.
You also seem to have had an issue with the multi function switch and aftermarket horn, steering column ground. You have purchased a wiring harnesses from Restoration Design. What harness or harnesses did you buy, and did they supply any documentation?
Also, don't discount ground issues. They can cause all sorts of issues if not correct. There are 3 main ground points in a 1973. One on the bulkhead by the drivers side frunk hinge, in the drivers fenderwell, and by the electrical panel in the engine compartment.
Also the rear light housing grounds by the rear bumper mounts.

Thanks Ed, yes quite a project car going here. Here are some more details.
Horn and steering column grounds are sorted out and working.
Wire harness was custom built from Restoration Design and the main harness and front trunk harness were built for a 73. The engine harness was updated to a 76 and for ITB's.
RD has been working with me to figure out the problem. Still no luck.

Here is where I stand. I have two issues
1. blinkers not working correctly
2. Hazard lights turn on when I pull the parking brake up

I believe it has something to do with the Hazard Relay

#1
With everything wired up, Blinkers are not working correctly
When I put on the left blinker, front and back blink as they should, but the right blinker also comes on dim
Same for the other side

If I remove the Blue/white (Emergency Flasher relay wire) to the back of the Speed gauge for the blinker illumination,
Blinkers works correctly, expect I have not dash blinkers since the blue/white supplies power. Each side blinks as it’s supposed to


#2
E-brake
When I pull the E-brake up, the red lights on the dash comes on and the blinkers blink
If I pull the blk/Green/white wire from the brake light switch and give it 12v power, the red light on the dash comes on as it should. Blinkers do not blink.


So, my two problems
Blk/whte/Green wire from Relay
And
Blue/White from Relay

Are both causing problems.

This is what I am down to.
1. I have not found the right relay that works with this set up

Or

2. Something is wired wrong to the Hazard plug. I checked the plug and got the following readings

I have all my grounds connected to those three points that you pointed out as well.

I do have a number of wires capped off, wiper motor, heater blower, license plate harness. All not needed to get the car started. I don't think those would be causing the issues I am having.

Not sure how to test the grounds.

Jared, IDR if I said this on another of your threads: Replace all the fuses with NEW. It probably won't fix this problem (although it might), but it will prevent other mysterious electrical problems. The open bullet fuses get old and tired, due to heat cycles and corrosion on the little metal strips. They develop tiny cracks that you may not see and that cause open or intermittent contact.

Do that every 10 years "whether they need it or not," and you will save yourself headaches. Fuses are cheap. Or you can do what others here have done and swap to the new fuse style fuse panels. Those are $400 or so, and take a day or more to install.

Pete, good advice but in this case he has new wire harnesses and fuse panels.
Jared, there are quite a few fuses that could probably be removed from you panel as they are not used, but should not be causing your issues.
I will try to get into your wiring a bit more soon.
To test your grounds, use an ohm meter connected to the brown wires and the other lead to the chassis. You should see very low ohms. High resistance means there is an issue.

thanks guys. I have a new fuse panel, so that is not the issue.
I have removed a few of the fuses as well. Here how my fuse panel is set up. You will see a few fuses have been removed.

I am down to two issues
Blinkers
E brake

Blinkers work when I remove the blue/white wires to the back of the speedo gauge (this gives power to blinkers lights) This means no turn signal lights on dash

E-brake, when pulled red light on dash comes on but hazards blink. If I remove the Blk/Green/white from the back of the park brake indicator bulb, it stops working (this is how it gets power). If I give the indicator light 12v power with the E brake up the dash lights up as it should.

I have tried 3 different relays.

Still not sure what the issue is.


http://forums.pelicanparts.com/uploa...1755623101.jpg

I'm going through the wiring a bit here and there. The fuse panel looks good except for lighting is reversed left and right.

http://forums.pelicanparts.com/uploa...1755721337.jpg

Thanks for looking at the fuse panel. What do you mean lighting is reversed, left and right ?

Still can't figure out this blinker issue. If I remove blue/white from the back of the dash gauge it all works right. Tried multiple relays, that does not seem to be the problem.

Thinking it's the harness???

The fuse position of the left lights is 1&3, right 2&4 originally, yours shows right 1&3, left 2&4. It's nothing that would make a difference.
I am wondering about the aftermarket tail light housings. There is something about the wiring there that seemed off in that thread. I have to revisit it.

E Sully and all others that tried to help me here. I finally figured out the problem, or Peter from Restoration Design figured it out.

I replaced my blinker bulbs with LED's - DON'T do that.

The LED caused all the blinker problems. When I removed the front blinkers bulbs and put in old school bulbs, the system all worked.

Problem solved.

Thank you Peter, Restoration Design wiring guru. You are the man.

Which blinker bulbs are you referring to? The exterior bulbs or the tachometer turnsignal indicators?

I think you still have issues. Installing LED turnsignals and running lights should not cause any issues except with the tach indicators. EP26 LED-compatible flasher relay corrects those. Folks change all their exterior turnsignal bulbs to LEDs with few issues beyond the flasher.

Before you found a solution with bulbs, it seemed your front turnsignals and/or headlights were not correctly wired. You said the rear turnsignals were bright but fronts dim. Regardless of LEDs or bulbs, front/rear should be bright. I think there's a ground in the front that needs attention. LEDs may exasperate an issue whereas incandescent bulbs may mask an issue.

Exterior blinker bulbs in the front, lower bulbs. I do have LED in the dash, but those don't seem to interfere. I also left the rear blinkers exterior LED and it works.

It could be a ground issue, but removing the LED blinker lights fixes the problem for now.

Do the LEDs in the dash work correctly? If you have LEDs in the rear of the car both L and R indicators in the dash may be both on together or off completely when the left or right turnsignal is on.

Generally if you have an OEM flasher relay with LEDs externally the OEM relay will not drive the L and R tach indicators correctly. LED-compatible flasher relay EP26 is a good replacement if the C2 pin is grounded internally.

Yes, Dash LED's work fine. No issues. I have a Wehrle
54 201 102 A E49 relay

Porsche OEM did not work at all.

At some point I will check the grounds and see if that was the problem, but I don't believe so.