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Discussion Starter #1
I got new everything when I was putting that all back together and spraying the inside of the trunk. The wiring harness is metal alloy even. Suddenly out of nowhere my left side brake/turn signal went out. Also have a new turn signal switch and harness. I already checked and even swapped out the bulb just in case it was in the bulb. Not the bulb. So I pull the push on cap end back off and it just has this disk thing in there. How do I test the thing? I don't think I even understand how that works. It isn't ground because the running light element burns fine. I think I'm starting to understand why places sell these pig tails. Since my brake light switch is just hanging at the moment I thought I would just wait until I get the kit in and fix it back right so then can see if the brake light part of the circuit it working. That would move the problem back to somewhere under the UGH, contortion dash. Guess I will be removing the driver side seat,,,,,,, again.

 

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The housing is grounded to the rear tail light panel, thus each lead is a power lead, one for running lights and one for brake/signal. With a volt meter you should be able to check the voltage from ground to both the inner and outer rings inside the pigtail. If you have voltage to both then the trouble is in the tail light bucket. If you do not then you need to work backwards. Starting at the pigtail check each wire for continuity.

Could your left turn signal wire have gotten pinched on a body panel, thus short out?
 

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After 400,000 miles, mine are still working just fine. You do need to make sure they are pushed in all the way, and clean inside. And of course my car has always been a complete, driven vehicle. If the car sits in the backyard, half stripped, as a semi-abandoned project, of course the wiring (and many other things) will deteriorate.
 

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Discussion Starter #6
Finally got the dvm out and tested the plug in cap on the wiring harness side. Both the center pin hole and the side bars show voltage so I would call it good. I get zip out of the light bulb side for the turn signal/brake light terminal. It looks like it is in the light bulb socket. I'm kind of thinking that maybe I should swap the 2 tail light buckets anyway to see if the problem moves just in case it is the connection itself that is somehow malfunctioning.

Is there a way to fix this or am I stuck having to get another tail light bucket?
 

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Tried some electrical contact cleaner spray?
 

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Discussion Starter #8
Yeah so I swapped the tail light assemblies and the not working left one works fine on the right side so I'm back to the left side cap or wiring somewhere.
 

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If you have a wire/voltage tester, test continuity from each pigtail end to the posts inside the socket. Could be you got a defective socket. The socket wall goes to ground. When you turn the lights on one pigtail turns one filament in the bulb on from one post in the socket. Brake or turn signal turns the other filament on from the other post in the socket so both filaments in the bulb are lit. With the lights off, both filaments light when brake or TS is on.
 

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Discussion Starter #10
Well I found the problem. I chased it all the way back to the front to that 2 pin connector that handles the left and right turn signal and stop lights. I unplugged just to verify it was the one and my right side turn signals also quit. Pushed on the connector pins just to be safe and plugged it back in. ITS MAGIC, LOL. I only wonder now how long it will go before it decided to carp out again. The turn signal and harness are new, the tail light assemblies are new, the wiring from front to back is all new. Gee. What could possibly go wrong with that.
 
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