Greg,

I admire your persistence, and you need some time off. Reread my edit in the last post (#38), about the wiring, and post your answer. Are you testing the black/gray wire at the fuse block and is it separated from the other wire?

L.J.

Thank you again. Sage advice, I am going to take an extended break. A combination of wanting to drive the car (six month driving season), a lack of confidence that I would actually be able to fix the problem without removing the entire front end, two weeks until the Pittsburgh Vintage Grand Prix and a spousal unit that prefers a front lawn lower than her knees has motivated me to go with the test wire. I buttoned up the car, test wire in place and turn signal working perfectly.

I am going to make this a winter project, but I am planning to do my motor this winter, so we will see how much time I have available.

Thank you again for all your assistance. I can't tell you how much I learned through this process, and I really gained a lot of diagnostic knowledge. Far from expert, but a great base to build upon. If I can ever return the favor, it would be my pleasure.

Greg,

Good to hear you're taking a break and going to enjoy the driving experience. You have found the problem (wire-to-ground) but not the cause though you have found a way around it. Enjoy the driving season and we'll wait for your posts next winter.

Turn signal problem
 

How do I remove the turn signal housing? I have the same problem, but I can only remove the lense cover. I don't know how to get to the back of the housing.

I can tell you what I did. Mine is an '86 with fog lights. I removed the fog light cover and let the back plate of the fog light hang down. There is an small cutout in the bottom of the bumper just above the fog light. It will allow you reach up from underneath to remove the two small (5mm i think) bolts on the back of the turn signal housing. There are two bolts in opposite corners of the housing holding it in place. It's tight. If you also need to remove the side marker, remove the turn signal first and you should be able to get at the side marker. If you can't get to the last (rear) bolt on the side marker, remove the bumper bellows and you can reach in from the back for the last bolt.

You should know even when you get the turn signal and side marker housing off, there is limited access. If you intend to just run an additional wire, you may only need to remove the windshield washer reservoir in the driver wheel well to see a wire being fed through the fender.

The previous post(s) have indeed brought you very close.

If the short (to ground) is between the fuse and the lamp socket,
there is only the black/white wire from fuse #9 to the headlamp assy
where a connector continues the circuit to your turn signal indicator.

Lift the black/white wire from the fuse panel.

Open up your left headlamp housing and:

Without a fuse or turn signal lamp installed, use your ohm-meter and test for a short to ground
on both sides of the two pin connector. (SW/WS) wire.

If you have a short, this test will provide the location of the short.

You are very close.

Purchase a Bentley manual, and a Fluke 77 on eBay.

A used fluke costs about $75 and is a very worthwhile investment for both
the car anad home.

Good luck,

Gerry

Here's a page out of my factory '86 911 Supplement.

Email me if you need any further assistance.

http://forums.pelicanparts.com/uploa...1248299246.jpg

Hi everyone, same problem in my '77 911S. Fuse blows only when I start the car and for some reason there is a constant 12V running through the turn signals circuit. I have isolated the most common cause (although I can't find the light in the engine compartment to disconnect?)

Seeing as how this is the most relevant thread regarding my 5A fuse blowing for the right-front signal ('75 911S), I'm hoping for a few useful answers. A few months back I lost my right front turn signal. The rear works fine but the dash just flashes both signals dimly. I finally got around to replacing the fuses after a few hour long internet search to find which rated fuses go where on a '75. The fuses all looked hideous, so I was hoping that replacement would solve the problem:

http://forums.pelicanparts.com/uploa...1461612276.jpg

Well.. unfortunately I spent the next few hours blowing through my new stash of 5A fuses. The left signal works perfectly, but as soon as I switch on the right signal the fuse instantly blows.

Here's what I've done so far:

Cleaned all contacts in the right-front signal bucket, replaced with new bulbs all the way around the vehicle, opened up the headlight bucket to check that those connectors were all solid and not crossed (the car does have upgraded H4's which work excellently), check ground points...

Which is when I also realized why my horn wasn't working as one of the ground connectors that comes out of the wiring harness was disconnected at the main ground location in the trunk:

http://forums.pelicanparts.com/uploa...1461613577.jpg

It's all tightly ground now and the horn works ~ fantastic! But still blowing 5A's on the signal.

Here's what I've noticed/what my questions are: the right front dual-filament bulb is EXTRA bright when the parking lights are engaged. I tried a different bulb and same overly bright symptom. Which seems to denote there is too much current flowing to that bulb, potentially blowing the signal fuse when I switch it on?

<s>Continuity/ground issues typically don't cause hot bulbs, yes?</s>

Could there be an issue with the turn signal switch on the steering column that would cause additional voltage to run that circuit?

What are some additional tests I can check for with the multimeter before I decide to rip apart the steering assembly again?

Could it be a flasher relay? Could it be wiring at the back of the tach gauge where the signals flash?

Thank you Pelicans in advance!

Ok.

One problem solved. Found that the right bucket was wired upside down (my fault as I was buttoning everything back together), so the 'flashing' fitment was given power instead of the smaller parking light filament. Swapped wires, put in a 5A, and promptly blew the fuse.

Still trying to work through this..!

Here is an additional question to add to my above list:

If I remove the bottom BLACK/GREEN wire from the #10 fuse circuit, put a fuse in, and it blows ~ would that indicate that the short is upstream of the fuse? Or is it likely to blow because the circuit is not complete?

Is the blk/grn wire the only one in the bottom of number 10?
If it is see if the bottom lug is shorted to ground.

I realized that I never closed this thread with the conclusion of my situation. Hope it helps others.

Ultimately, I bailed and took it to a local Porsche independent - (Pete's for you western PA guys). He concluded that reversed two wires on the same turn signal. He simply reversed the upper and lower connections on the light the was causing the fuse to blow, and all was good. It seemed really odd to me that this would cause the issue, but that's what was communicated to me.

So just to clarify and for others who may find this thread, your earlier image would then be mis-labeled as to which cables go to the 'top' and 'bottom' of the front turn-signal assembly, correct?

I think this may have happened to me which is why when I put the bucket back together I had an extra bright filament instead of the usual one that gets used for the parking/running lights.

Pete,

The bulk/grn wire is the only wire at the bottom of the #10 fuse position. If the 'lug' you are referring to is what holds the bottom of the fuse as well as the wire, it does not read as shorted to ground.

Pulling hair...
 

OK, just another update: I ended up pulling the steering wheel and gauges out. I found that I had put back two bulbs at the back of the tach in the wrong position. After resolving that, I found an unattached green cable floating behind the oil temp/pressure gauge and found it's missing spot on the TEMP side light. Thought I'd give the circuit another go and blew the fuse.

http://forums.pelicanparts.com/uploa...1461722726.jpg

I now have the Hella flasher pulled and noticed that one of the connections looks 'burnt', or severely darkened.

http://forums.pelicanparts.com/uploa...1461722777.jpg

I'll try replacing this unit and see what happens.

I'm sorry, it's been too many years (7) for me to remember that level of detail. However, to anyone finding this in the future, I would advise them to pay attention to this level of detail as it matters. Check the other side, check another car, reverse them, etc. Bottom line, connecting to the correct male prong matters.

1986 US 911 coupe. I’ve been experiencing blown 5A turn signal fuses lately too. Don’t need more excuses to be pulled over. I don’t have a multimeter, and have blown about 20 fuses trying to figure this out...I’ve also been reading through many chats here on Pelican and elsewhere on the net. I have 100 fuses on order and have decided that a majority of the problems have to do with how the lights are wired. The other important point is that the left and right lights are the same, one merely the other rotated 180 degrees.
Using the driver’s light as a reference, the backside of the reflector should have white/grey at top, black-white at bottom, and the brown/white in between.On the housing part (affixed to the vehicle) the white/brown should be at top with the white at bottom. If you’re doing the passenger side, invert...
Finally, while in there, clean contacts with wire brush or similar. In the event some of the transparent insulation comes off or is split, cover with heat shrink.
As I await my batch of fuses, hope this helps other owners.
Happy holidays.