# 69 tail light problems



## 69bfam (Jul 17, 2011)

i got a new wiring harness from the dash back to the tail lights. pluged it up and grounded it and the only lights that come on when i turn the lights on are the side markers.no running lights,both side markers blink when you turn the blinker on. i belive this to be a ground problem but the only ground on the harness is grounded. very well...are there any other grounds im missing or what. ive been playin wit this thing for two days


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## freethinker (Nov 14, 2009)

69bfam said:


> i got a new wiring harness from the dash back to the tail lights. pluged it up and grounded it and the only lights that come on when i turn the lights on are the side markers.no running lights,both side markers blink when you turn the blinker on. i belive this to be a ground problem but the only ground on the harness is grounded. very well...are there any other grounds im missing or what. ive been playin wit this thing for two days


lights ground through the body.there should be ground wires that connect to the trunk lock assembly. then it grounds through the body through the body ground straps in the engine compartment. that completes the circuit back to the battery. do you have any engine to body ground straps hooked up?


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## 69bfam (Jul 17, 2011)

how many grounds are there supossed to be. theres only 1 comeing off the harness and that is on the trunk lock. i have 1 ground going from the frame to the fire wall in by the engine. and a ground from the battery to the engine.


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## 68greengoat (Sep 15, 2005)

Check out this thread. Post #13 shows needed grounds.

http://www.gtoforum.com/f12/turn-signal-not-working-67-gto-27334/


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## freethinker (Nov 14, 2009)

69bfam said:


> how many grounds are there supossed to be. theres only 1 comeing off the harness and that is on the trunk lock. i have 1 ground going from the frame to the fire wall in by the engine. and a ground from the battery to the engine.


to complete the circuit you need an engine to frame or body ground.


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## ALKYGTO (Mar 29, 2010)

I had to run individual grounds on each light for them to light up properly. Had to run a separate ground for the front parking lights also. My battery is in the trunk so I have it grounded to the frame there and heavy grounds from the frame to the engine block. I'm not sure why these cars seem to need all this but my friends 69 GTO is the same way as mine, additional grounding made huge improvements to interior and exterior lighting.

Almost forgot to mention, you really need to ground to clean bare metal. Just running a sheetmetal screw won't really do it. You need to grind any paint away to bare shiny metal where you run your ground wire to the body.


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## 69bfam (Jul 17, 2011)

theres got to b a better way. that sounds like alot of work for brake lights


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## Eric Animal (Oct 28, 2007)

Proper grounds are JUST as important as proper hot connections. They are the other half of the circuit! The 69 GTO is notorious for having "weak grounds"........Take the time and add some. Your lights, and accessories will work better!!! eric


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## Joe C2 C5 (Apr 13, 2011)

Just a simple thing but are the factory ground straps still on the rear tail light housings? These are often overlooked and they are definitely needed for grounding.


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## Eric Animal (Oct 28, 2007)

Do it ....and like it!:lol:


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## bigrc2 (Mar 28, 2009)

Here maybe this will help! This is factory!


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## 69bfam (Jul 17, 2011)

*yea buddy*

that was it thanks for the pic.s. i just cant see why they would make it like that. should of just made the light houseing metal...


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