Topic: Interior lights will not work
in Forum: C3 Electrical
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Hi everyone
new to the forum. I just purchased a 71 C3 t-tops.
I feel like i have committed polygamy.
this car is like a second wife.
I am making repairs (as I guess you always will) and have replaced the door jamb switches.
I cannot get interior light to work.
if I ground one side of the fuse with a test light the lights come on.
I am guessing a bad ground somewhere.
anyone know where to find that ground???
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Lifetime MemberHOWELL, NJ - USA
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Vette(s): 1979, Targa Blue (72 Color), Pace Car rear spoiler, L88 hood, Dark blue factory interior, 525HP 406, HD 700R4, 370 gears,Steeroids, composite rear spring, TT IIs wrapped in T/A Radials.
Welcome to the forum!
The ground is most likely integrated into the interior harness. Best to look at a wiring diagram if you have one. If not Joel (aka Adams Apple) might be able to help you with a copy.
Just looked at my wiring diagram and it looks like the ground for the interior lamps is in the ign switch harness...
Good luck!
Paul
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Paul
thanks for the heads up. i am under there riight now and sorry I started to look.
Lots of cut wires, disconnected etc.
I have to get a wiring manual.
I grounded one side of the fuse and the llights work.
so i figured a bad ground.
Paul
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Frederick, MD - USA
Joined: 9/8/2003
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Vette(s): 1969 convertible L71 427/435 4-speed black interior
Fiberglass cars are different from metal cars so they're wired differently by necessity. In metal cars the door jamb switches are self-grounding and opening the door completes the hot circuit. In a 'glass car the switches are grounded by a wire and are always hot and opening the door completes the ground.
To make it easy, try running a ground wire from the door jamb switch direct to a metal ground so you don't have to mess with the wiring harness. It should accomplish the same thing.
Thanks gunslinger.
If i run the ground to one jamb switch will all of the lights work even the other side switch or do i have to run a ground to all.
Lifetime MemberLemon Grove, CA - USA
Joined: 10/17/2007
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Vette(s): 1982 C3 Collectors Edition 44000 miles, sat in the sun most of its life, My wife purchased it for me for Father's Day in 2007 from her girlfriend that had it for 19 years. It is on the road again. I'm retired but it is now my daily driver.
I would assume that your 81 is like my 82 when it comes to the interior lights. If the dash lights work then is looks to me that your basic ground for all interior lights is working as it seems that most go to the same grounding point. That would mean that the bad ground wire could be where the different circuits tie together. The ground point is 101 have no idea where that is on the car.
Bottom line would be that I do not know how many separate ground wires you will have to run if only some of your inside lights are off. If on the outside chance none of your interior lights work then it is basically the single ground point that is bad and it may be worth trying to find that point.
My manual does not show the complete car wiring it only shows individual circuits so it really is hard to see. Maybe Adam has some specific trouble shooting ideas for the system that could help.
Check this site:
|UPDATED|1/27/2013 7:19:13 PM (AZT)|/UPDATED|
The ground is at the right door jamb switch according to this diagram.
|UPDATED|1/27/2013 7:19:13 PM (AZT)|/UPDATED|
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The door jamb switches for the interior lights are screwed into the metal of the birdcage....which provides the ground for the pin switches. The most common problem is that the tiny terminals on the pin switches will break, leaving the wire to just flop around, and not work the interior lights.
If the interior lights come on when you turn the headlight switch full counterclockwise, then you probably have bad pin switches, as in the terminals have broken off. You can buy replacement terminals and replace them yourself, or you can purchase new pin switches.
If you remove the kick panel on the driver side(or passenger side), you should be able to see the back side of the pin switch....and prolly a loose wire that goes to it.
If the interior lights come on when you turn the headlight switch full counterclockwise, then you probably have bad pin switches, as in the terminals have broken off. You can buy replacement terminals and replace them yourself, or you can purchase new pin switches.
If you remove the kick panel on the driver side(or passenger side), you should be able to see the back side of the pin switch....and prolly a loose wire that goes to it.
Joel Adams
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thanks for the help.
yes you are correct there is one ground point.
Case75 was right on the money with the wiring diagram.
Great !!!
I am able to follow the wires back to the ignition switch. that is where the ground goes.
I will get back in there and follow that.
thanks again
Paul
Adams Apple;
i pulled both kick panels and replaced both jamb switches.
the right switch only has one wire to it.
the left switch has two.
the ground from the left switch goes thru the ignition switch.
I have to get back under the dash and check that out.
i also have a few cut wires i need to figure out.
thanks for the help.
Paul
in Forum: C3 Electrical
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