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TAIL LIGHTS.....DEAD???

  • Thread starter Thread starter RaZoR1017
  • Start date Start date Oct 2, 2009
R

RaZoR1017

New Member
Sep 24, 2009
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Delco, Pa
Oct 2, 2009
#1
  • Oct 2, 2009
  • #1
Hey all! I have this 1991 gt that I recently got and I had to replace all of the rear bulbs. When I hit the switch to put on the headlights, the headlights work but the tail lights do not...I don't even know where to start on electrical things....just wondering if someone can help with getting me to a starting point like a harness to check for shorts or cuts in a wire??? Any help will be wonderful thanks!!!
 

mob

the guy who hits on his mom
20+ Year Stangneter
Oct 3, 2003
2,566
136
104
Dallas, TX
Oct 2, 2009
#2
  • Oct 2, 2009
  • #2
This happened right after you put in new bulbs? I would ensure you put the correct bulbs in there. I believe our tailight bulbs are double filaments, I am pretty sure if you put the single filament in, they wont turn on at all.

If you have the correct bulbs, get a multimeter and check the wires right behind the bulb. Put the key in, turn the lights on, and there is probably 3 wires coming out of the socket, black is ground, check the other two one should have close to 12V.

Also just check the fuse for good measures.
 
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RaZoR1017

New Member
Sep 24, 2009
10
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0
Delco, Pa
Oct 3, 2009
#3
  • Oct 3, 2009
  • #3
Checked the fuse...thats all good.
The bulbs I looked up online at autozone...and got that bulb number. It did not say anything about double filament? If there was a short there or a bad wire would it mess up the entire circuit including the headlights? Cause like I said those are working great?
 

7upstang91

10 Year Member
May 30, 2008
936
124
74
Florida
Oct 3, 2009
#4
  • Oct 3, 2009
  • #4
Do your dash lights come on as well when you turn your lights on? If they don't either then the light switch itself it bad.
 
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RaZoR1017

New Member
Sep 24, 2009
10
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0
Delco, Pa
Oct 4, 2009
#5
  • Oct 4, 2009
  • #5
Yeah the dash lights...the hvac lights are all good?
 

Repostyle

Member
Jun 11, 2005
538
0
16
Portland, OR
Oct 4, 2009
#6
  • Oct 4, 2009
  • #6
Basics first, since your dash lights come on it's not the fuse. These cars do use the same bulb for both brake and tail so it would be a double fillement. Make sure you got the right bulbs. If you have the right bulbs, check for power at the lights, just use a test light. Do the license plate lights work? Do the brake lights work? If the plate lights work and you have the right bulbs, then it's probably an easy fix in the trunk to find a bad wire. If the brake lights work then it's not the ground, it's a power issue. If it's a power issue and you have the right bulbs, you'll have to test and see which wire is tail and you can just get power from the license plate lights for an easy "duct tape and bailing wire" temporary fix. But finding the actual issue is important, as a bad wire shorting out could possibly start a fire in the trunk.

Just need to get in there and get your hands dirty a little, chances are you don't have the right bulbs.
 
R

RaZoR1017

New Member
Sep 24, 2009
10
0
0
Delco, Pa
Oct 4, 2009
#7
  • Oct 4, 2009
  • #7
Thanks for the info.....The brake lights work....but the license plate lights do not work. Like you said I am going to need to just jump in and start looking at everything. thanks again!
 

Repostyle

Member
Jun 11, 2005
538
0
16
Portland, OR
Oct 4, 2009
#8
  • Oct 4, 2009
  • #8
yup, it sounds like a bad wire since nothing in the back is working. Just have to start checking for power and ground.
 
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