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Discussion Starter #1
Hoping someone might have a quick tip about an electrical issue I'm having on my B5 :wrench:

- turn signal & hazard fuses repeatedly blow
- hazard relay buzzes when actuated
- replaced hazard relay, same deal
- pulled all turn signal bulbs, same deal
- pulled out the CCM, harness seems in good shape down there.

So it smells to me like I've a short somewhere (since it occurs via either the turn signal being actuated, or the hazards, thus ruling out the turn signal switch). I'm <this> close to tracing back the full harness corner-to-corner for the turn signals. Anyone know of common spots for short-to-ground damage to occur?
 

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it smells to me like I've a short somewhere
I agree with your diagnosis. Have you tried unplugging the CCM to see it changes anything? If the car has any collision damage, look in those areas for pinched harness's. If the car ever had any cracked tail light fixtures or front corner fixtures, inspect the bulb sockets for signs of corrosion. Which fuses are blowing? That info will help isolate the shorted circuit.
 

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Have you tried unplugging the rear bulb holders/ plates? Also, try unplugging the CCM like Steve suggested.
 

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Discussion Starter #5
Thanks for all the suggestions; I'll try pulling the rear bulb-holders this evening, and the CCM.

Either the indicator fuse (#2) or the hazard fuse (#39?) blow, when their respective switches are activated (though now I think about it, I need to verify if the indicator fuse blows for actuation in either direction, or just one side).

There is a small crack in the rear-right lamp cover, but no visible corrosion apparent on the bulb holder.

The car was involved in a minor side-on collision (left side, so passenger side; we're RHD here) ~6 years ago. It also suffered from the classic passenger-side leak in the past, but that's been cured for the best part of a year now (dry as a bone around the CCM and harness).
 

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i had a similar problem to this a while back with the turn signal stalk on the steering wheel. unplug it, and put the fuse back in to see if the problem persists.
over the life of my car i have had to replace mine TWICE. 02' ym.
 

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Discussion Starter #7
So today I disconnected

- all bulbs
- CCM
- turn signal stalk
- bulb holders at rear

and I still see a voltage at the fuseboard once the hazard switch (replacement one) is actuated. More harness digging for me :)
 

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Discussion Starter #8
In a follow-up to this, I tracked it down to the left side. Stripped out seats, boot liner, kick panels etc., to get at the left-side harness. Disconnected the one connector I could find in the left A-pillar with the appropriately coloured wires, started rooting around the harness looking for badness, pesky short disappears :) So it's either to do with the connector I undid, or in the harness going to the left-rear lights.

For anyone digging at things similar to this in the future, go for it; it's not half as bad to get at as I thought it would be.
 

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I agree with your diagnosis. Have you tried unplugging the CCM to see it changes anything? If the car has any collision damage, look in those areas for pinched harness's. If the car ever had any cracked tail light fixtures or front corner fixtures, inspect the bulb sockets for signs of corrosion. Which fuses are blowing? That info will help isolate the shorted circuit.
I have same issue and in my case the left turn signal blows the 10a no:2 fuse. The emergency signal buzz and blows out same fuse. The right turn signal works perfectly. Any help?
 

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Yes, the left turn signal previously worked perfectly until I had an electrician check the parking light which stopped working for a reason I didn’t know. I have replaced the turn signal fuse about 5 times now.
 

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Did your left turn signal previously work correctly, or is the car new-to-you?
Do you have a multimeter and any electrical skill?
[/QUOTE
Yes, the left turn signal previously worked perfectly until I had an electrician check the parking light which stopped working for a reason I didn’t know. I have replaced the turn signal fuse about 5 times now.
he still couldn’t fix the parking light ish.
 

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The parking light he was working on is probably the source of your trouble.

The (front) parking light uses the same bulb as the turn signal. It's a double-filament lamp--one low-wattage filament for the parking light, a second higher-wattage filament for the turn signal. The shell of the socket is common to both filaments. There are two contacts on the bottom of the bulb, one for each filament.

If the bulb is forced in the socket incorrectly, the two contacts on the bottom can be shorted together, which will overload circuits. I'd start by removing that bulb, then make sure it's the correct bulb and installed correctly. Notice the two tits on either side of the base are not symmetrical--the bulb should go in its socket easily.

There's an outside chance the wiring in the headlight assembly has issues (sometimes the insulation would flake off due to heat), but that's less likely.
 

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The parking light he was working on is probably the source of your trouble.

The (front) parking light uses the same bulb as the turn signal. It's a double-filament lamp--one low-wattage filament for the parking light, a second higher-wattage filament for the turn signal. The shell of the socket is common to both filaments. There are two contacts on the bottom of the bulb, one for each filament.

If the bulb is forced in the socket incorrectly, the two contacts on the bottom can be shorted together, which will overload circuits. I'd start by removing that bulb, then make sure it's the correct bulb and installed correctly. Notice the two tits on either side of the base are not symmetrical--the bulb should go in its socket easily.

There's an outside chance the wiring in the headlight assembly has issues (sometimes the insulation would flake off due to heat), but that's less likely.
WOw! You have just explained it all. That’s exactly what he did. I saw him forcing the bulbs in the sockets nd mixing the up. It was after he forced the bulb in I notice smoke in the fuse box and almost all fuses blew. Had to replace blown fuses. But the left turn signal fuse keeps burning out when I put it on. How do I fix this? Any help?
 

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There are probably damaged wires and/or melted insulation and now there is a permanent short in the wiring. You'll have to find and repair the damaged wires. I'd start by just physically trying to trace the wires from the fuse box to the sockets. If you can't find it that way, you'll have to debug the problem with a multi-meter and schematics, etc. or take it back to the guy who burned it up and have him do it.
 

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I wouldn't have that "electrician" touch that car again, but he should be liable for damages. Especially if you paid him to work on your car. At the very least a full refund of the service, or rather disservice.
 

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Reread post #13. Remove the front turn/park bulb from the socket; that may clear the issue. You'll then have to install the correct bulb the right way.
If you're not comfortable doing that, I'd certainly find someone else to work on the car (as VAGguy said).
 
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