Brake light mystery - 79 TransAm

M

mpsfun

I have a nice original 79 T/A with the mighty 301 4 speed.This car has sat for over ten years (covered in AZ) Baked is a good description. I noticed when I got the car powered up that when I pressed the brake pedal the dome light would come on. Well in the past few months the car has a new interior and now I noticed that I have no brake lights and the dome does not work either. I have running lights, turn signals even the cigarette lighter works. I replaced the turn signal switch in the column (NAPA part) checked for voltage (there is voltage present in the dome) so I assume there must be a bad ground..but where? Does that circuit ground though the emergency brake assembly ? that is the only item not back in yet.... anybody have any idea on where to start?
Thanks,
MPSFUN
 
M

mpsfun

I have a nice original 79 T/A with the mighty 301 4 speed.This car has sat for over ten years (covered in AZ) Baked is a good description. I noticed when I got the car powered up that when I pressed the brake pedal the dome light would come on. Well in the past few months the car has a new interior and now I noticed that I have no brake lights and the dome does not work either. I have running lights, turn signals even the cigarette lighter works. I replaced the turn signal switch in the column (NAPA part) checked for voltage (there is voltage present in the dome) so I assume there must be a bad ground..but where? Does that circuit ground though the emergency brake assembly ? that is the only item not back in yet.... anybody have any idea on where to start?
Thanks,
MPSFUN

Looked at this a bit more.. I put a bulb in the trunk light, it did not work but I noticed that when i opened the truck the dome came on. with the trunk open if you turn the light switch so the under dash lights come on (they do come on when the door is open- just not the dome) the dome goes out. if you are in the car with the trunk open, doors shut and step on the brake pedal the dome gets brighter like the brake lights should. and if the trunk in closed and the doors are closed the dome does come on (very brightly) when you step on the brake. So to me the brake switch is good, there is power back to the light connector in the trunk and a ground for some at least ...the only thing not going on in one way or another is the brake lights...although I know they are good as the turn signals and running lights work....

Thanks,
MPSFUN
 

Redbird 79

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I feel your pain. I have a 79 esprit redbird. With trans/am tail lights. I havent had any issues with it till today. My dome light came on while driving and I realized that I didn't have brake lights when moving the car tonight. I've been going over the wiring diagram and the brake switch is so far my only lead as to what could be bad. My trunk light used to work. And stopped working about a year ago. I have been meaning to look into that issue until tonight.
 

Redbird 79

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I have a nice original 79 T/A with the mighty 301 4 speed.This car has sat for over ten years (covered in AZ) Baked is a good description. I noticed when I got the car powered up that when I pressed the brake pedal the dome light would come on. Well in the past few months the car has a new interior and now I noticed that I have no brake lights and the dome does not work either. I have running lights, turn signals even the cigarette lighter works. I replaced the turn signal switch in the column (NAPA part) checked for voltage (there is voltage present in the dome) so I assume there must be a bad ground..but where? Does that circuit ground though the emergency brake assembly ? that is the only item not back in yet.... anybody have any idea on where to start?
Thanks,
MPSFUN
Ok so I sorted out the problem. Check the 20A stop lamp fuse. Mine looked good at first till I tested it and it was blown. Replaced the fuse and problem solved.
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melsg5

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Ok so I sorted out the problem. Check the 20A stop lamp fuse. Mine looked good at first till I tested it and it was blown. Replaced the fuse and problem solved.
He hasn't been here in 13 years. Good to hear it was only a blown fuse.
 
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