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-   -   Chasing electrical gremlins (https://forums.maxperformanceinc.com/forums/showthread.php?t=884523)

prostreet64 03-07-2026 11:40 AM

Chasing electrical gremlins
 
On my 79 T/A the stop light circuit is whacko. As I understand it the stop light fuse/circuit controls the brake lights, the emergency flasher and the dome light/trunk light. When I turn on the e-flasher the brake light element does not blink but the dome light and trunk light do blink. When I depress the brake pedal the tail light elements come on, not the brake light element which is the brighter of the two elements in those 2-element bulbs. I have checked and replaced bulbs to no avail. Am I looking at a loose hot lead or maybe a loose ground connection? Don't know what to do next.

"QUICK-SILVER" 03-07-2026 05:48 PM

Check the ground wire in the trunk.

Double check that both dome and courtesy light fuses are good.

Clay

prostreet64 03-07-2026 09:38 PM

I have a schematic for 1977 and I assume it would be the same for 1979? Anyway, the schematic shows two ground locations in the trunk, one for each side but I can only find one ground wire and it is on the left side near where the rear harness goes into the light assembly. Should there be one on the right side or is the one serving both? More looking tomorrow. Thanks

"QUICK-SILVER" 03-08-2026 11:22 AM

Thinking 79 just had the one ground wire.

With eight tail light bulbs, tag lights, backup lights... Could be a bad connection in one of the splices.

Clay

prostreet64 03-08-2026 05:00 PM

Here is the latest. Cleaned up the ground connection although I don't think it was the issue. Replaced the remaining bulbs that I hadn't already replaced. I put the stop light fuse fully in on the right hand side, but I only set it up against the contact on the left. Didn't want to push it all the way in case I needed to remove it again. Anyway, at this point everything worked. Brake lights, flasher, dome and trunk lights. So I seated the fuse fully into the holder and now nothing was working. I removed it and did as before with only the right side seated. Everything on again! I will remove the fuse box tomorrow and have a look. Never done that before so are there any things to look out for?


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