Problems with headlights and signal lights

[sballard]

My car (stock '72 911T Targa) has sat mostly idle for about 10 years as I have undertaken a number of projects including disassembly for a fresh paint job and various mechanical issues. The car is pretty close to being ready for regular use, but I have a confounding electrical issue.

With the ignition "off", the "right" or "left" signal lights will light up (both front and rear) if the signal switch is turned "right" or "left", respectively, but they do not blink. I assume that this is normal.

The headlights only come on when the ignition is switched on. But they only come on when the turn signal switch is in the "middle" position, which I assume is supposed to activate the "high" beams (the blue dash light comes on indicating high beams). When I push the stick to the forward position, which I believe is suppose to activate the "low" beams, the headlights go out. When I pull the stick all the way back toward me, which is suppose to flash the headlights, the headlights go out.

The tail lights and signal lights will come on when the ignition is on or off but they do not blink.

I've pulled out the turn signal switch and looked it over and it looks like the contacts are working. Unfortunately, I don't see any reasonable way to get access to the electrical contacts. I've seen multiple threads where people are able to access the actuators and bend them to make better contact, but I see no way to do this without destroying the switch.

Any advice? I can buy a new switch from Pelican, but it's $$$. Of course I'd prefer to repair it if possible. And I am not 100% sure that the switch is the problem.

[Canada Kev]

Originally Posted by sballard

With the ignition "off", the "right" or "left" signal lights will light up (both front and rear) if the signal switch is turned "right" or "left", respectively, but they do not blink. I assume that this is normal.

Yes, this is normal.

Originally Posted by sballard

The headlights only come on when the ignition is switched on.

This is also normal. However, the "middle" position in my car is for the standard low beams. Pushing it forward, it notches into the high beam position. Pulling the lever towards me gives a momentary high beam flash.

I have no advice on your turn signal switch.

[sballard]

Kevin-

Sorry I made a mistake. According to my owner's manual, high beam normally requires the lever to be pushed forward as you describe.

However, in my car now, high beam, at least as indicated by the blue dash light, is activated with the lever in the center position.

[Rodek]

I have a '78 and recall reading somewhere that when the car is turned off and when you turn the turn signal lever left or right, that side of lights will come on. This is for when you park on the side of the street, you can illuminate the side of your car that is closest to or is still partially in the street. I recall seeing cars do that while I lived in Europe several years ago. Some of the streets were a lot narrower than what we have here. By the way, good to see someone near me. I live in Wetumpka.

[T77911S]

so you took it apart and now have put it back together?

its probably not the switch, the wiring is wrong.
middle is low beams. forward in hi beams.
headlights do not come on with ign off but the park lights will

the left and right thing is normal as said

[sballard]

Thanks T77911S. I've got the the manuals so I'll start pouring over the electrical schematics and see what I can find.

Rodek - Glad to know there is another Pelican nearby. Wetumpka is a beautiful area - great roads for Porsching!

[sballard]

T77911S - man you were right on the money!

My fuse panel looked pretty dirty so I went through each fuse and cleaned them up. After that, the turn signals worked!

Unfortunately the high beams still do not work. I noticed that the fuse for the left high beam did not have a wire connection on the right side. The left side had a white wire and a white/blue and no wire on the right. The right high beam fuse had a white wire connected on both sides.

In my schematic below, it looks like there might be a jumper between the #1 and #2 fuses on the left side but I am not certain. Is this correct? I really don't want to do any damage here until I am sure.

[T77911S]

its a jumper. usually a solid medal one.

what I did on my 930 was remove the white wire(if that is the one from the switch) and run it to the coil of a separate relay. then from the switched side of the relay I ran it back to the fuse block.
power for the headlights came directly from the battery, thru the relay then to the fuse block.

(very short description).
this eliminated all the current going thru the stalk. I also run 60/100 bulbs.
did that for boot hi and low

[sballard]

Since the lone remaining issue is the bright lights (and flasher), I cleaned the connections of the bright light terminals at the fuse bank - that did not help. Then I took off the flasher mechanism again and managed to run some emery cloth across the contacts. I could tell that I was getting some bite in the contacts. But, when I put everything back together, still no bright lights or voltage at the bright light fuses.

I guess the next step is crawling through the wires between the fuse box and the dash. I hate to think about it! The little voice in the back of my head is still whispering "it's the flasher." But at $400+, it's my last option.

[T77911S]

test test test before $$$$

[sballard]

For most of yesterday and today I decided to attack the turn signal/flasher issue. As noted above, I was able to get the leads of my volt/ohm meter to the high beam/low beam contacts of the switch. As before, there was continuity between the low beam contacts but not high beam contacts. The gap between the contacts was too narrow to get any sort of file in between them, so I tried several grades of abrasive paper. Started with very fine emery cloth which was ineffective, then moved to 2 slightly more aggressive sand papers. I finally got continuity across the contacts. Put it back together and no high beams. Then I used a slightly higher grade abrasive. Again, I got continuity but still no high beams. So there is a problem beyond the switch. I know from previous ventures into the dash that a previous owner has mucked around with some of the wiring so this will be an adventure. Double oye!

[Tremelune]

Wait, so...you're current issue is that the high beams come on in the low beam position, and the low beams simply do not come on?

If I were you, I'd check voltage at the fuse box and see what's happening. It sounds like some wires are reversed and there is a bad ground somewhere. Then I would wire the headlights with a pair of relays from the fusebox. That prevents the current from going through the pricy switch, and will very likely put a higher voltage at the bulbs, which means greater light output (voltage drop can be measured beforehand).

[sballard]

Tremelune - Actually, it is the reverse. The low beams work (middle position of the light flasher/turn signal), but the high beams do not (forward position). There is no voltage measured at the two high beam fuses, but there is voltage at the low beam fuses. At this point, it looks like the light flasher/turn signal is working but no current is flowing to the high beam circuit.

[sballard]

Can anyone tell me where the headlight flasher changeover relay is located? The wiring schematic indicates that it is located somewhere between the fuse panel and the light flasher/turn signal stalk.

[timmy2]

Behind the gauges. Access from trunk.

[sballard]

Closing in on the cause of the problem I hope...

I ran a wire from the high beam fuse block to the turn signal/flasher stalk and measured the electrical continuity. At low beam setting, there was continuity with the white/black and yellow wire posts (both the low beam wires) and only the red wire on the high beam post. The white wire on the high beam post did not have continuity. So there appears to be a break in the white wire circuit back to the fuse box.

I assume that the round relay at the bottom arrow is the headlight flasher changeover relay as the white wire from the fusebox ran to it.



I opened up the relay and the contacts were bent and probably not making good contact.



Might be the problem. I'll order a new one and see if this is the culprit.

[sballard]

I've been pretty busy since my last installment, and I regret to say that I haven't fixed the problem. Any suggestions/comments on productive directions are welcome.

Here is what I've found so far...

The headlights work when the flasher is in the "middle" position. This is theoretically the "low beam" setting. However, the blue light in the dash is on, which according to my manual indicates that the lights are on high beam.

When I push the flasher to the forward position, which according to my manual is the high beam setting, the headlights go out completely. Similarly, when I pull the flasher toward me from the middle position, the headlights also go out completely.

Headlight wiring: When the headlights are wired according to the manual (as looking from behind the headlights - ground wire to the top connector, yellow wire to the left connector, and white wire to the right connector), the headlights come on, but only when the flasher is in the middle position. If I switch the yellow and white wires with their respective connectors to the headlights, the lights will work the same.

When the battery is installed and the ignition "on" (engine not running), I measure 11.6 V at both "white" wire (high beam) and "yellow" wire (low beam) fuse terminals when the flasher is in the middle position. When I push the flasher to the forward position, I measure 0 V at the white and yellow wire fuse terminals.

I unbolted the flasher mechanism while keeping the wires attached and measured the voltages at various points. Four wires are attached to the flasher. Toward the side facing the driver, there is a white/black wire on the left side and a yellow wire on the right side. On the side facing the dashboard, there is a red wire on the left and a white wire on the right (see images).






With the ignition ON and the flasher in the middle position, the voltages at each wire terminal was
Yellow: 11.0 V
White: 11.4 V
Red: 11.2 V
White: 9.7 V

With the ignition ON and the flasher in the forward position, the voltages at each wire terminal was
Yellow: 11.4 V
White: 11.4 V
Red: 11.5 V
White: 11.5 V

With normal wiring at the headlight (ground brown wire, yellow wire and white wire), headlights work only when the flasher is in the middle position. With only the white wire disconnected, there is no change (the headlights work only when the flasher is in the middle position). With only the yellow wire disconnected (both ground and white wires are connected), the headlights do not work.

With the ignition off, I measured conductivity between the high beam fuse terminal and the 4 wires that attach to the flasher. At the flasher, I get conductivity between the fuse terminal with red, white/black, and yellow wires, but not the white wire. When I put the flasher in the forward position, I get conductivity at the red and yellow wires only.

I guess I can assume that there is an interruption in the white wire signal somewhere between the fuse terminal and the flasher. I swapped out the headlight flasher relay, located behind the dash, with a new one but I didn't notice any change. While swapping it out, I measured conductivity between the high beam fuses and the relay connectors, so I assume that there is no issue to that point. Everything else in there is heavily wrapped with tape. I suppose my next job will be working my way through that.

Am I going about this correctly? Does anyone have any suggestions or comments that can help me solve this problem?

[Tremelune]

This is weird. It seems like all wires at the switch are hot all the time. Are the lights switched by connecting them to ground?? Wish I had a diagram of it...

Another thing you can do is disconnect the battery, provide power directly to the points on the switch (with a power supply or 9V battery), and see what you get at the fuse. If you're certain that the grounds for the headlights are sound, it sure seems like the switch or a wire is damaged.

[sballard]

I have some electrical know how, but I admit that my knowledge is pretty basic.

I believe that it may be functional that the flasher switch has two hot circuits - a low beam circuit and a high beam circuit. When the flasher is pushed to the forward position, the contact is physically moved to connect to the high beam circuit contact. It would make sense that both high and low beam circuits are always active, and the contact "switches" from the lower circuit to the upper circuit to route the current to the high beams. Perhaps an expect can chime in here.

I've been thinking today that the flasher switch may be capable of making electrical contact with the high beam circuit, but maybe the contact is weak and it can't carrying enough current to get the high beam circuit to light up the headlights. When I first started working on this, the switch did not make an electrical contact with the high beam circuit. I had to run some fine sand paper on the contacts before I got a signal.

[sballard]

This morning I ran a wire from the positive battery terminal to the high beam fuse block. The lights came on. Then I did the same with the low beam fuse block. The lights came on. So I at least know that part of the circuit is functional.