#1  
Old 05-17-2010, 10:23 AM
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garrity455 garrity455 is offline
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Default blowing brake light fuse over and over

Hey guys. I keep popping the brake light fuse in my 79 trans-am. I know when it blows, the dome light goes out to. Easy way for me to realize it.

But I am not sure if it is the dome light or brake light that is causing the issue. There isn't some common issue I should look for is there?

Thanks,
mike

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Old 05-17-2010, 11:13 AM
Pontirag Pontirag is offline
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remove one bulb at a time and see if the fuse blows. make sure the bulb contact in the base of the socket does not touch or ground out when you remove the bulb to do this test. do all the brake light bulbs and the dome lite

Make sure the fuse you install is proper rating

check the light switch that turns one the dome light when the door opens.

check the brake switch up under the dash

check up under the dash for any moving parts that migh have worn away insulation

look in the trunk area for any damage to wiring that occured when something was put in the trunk(spare tire, jack cargo) that might have pimched or damaged wiring.

finally trace individual wires from power source to the dome and brake lites.

  #3  
Old 05-17-2010, 11:49 AM
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Look at the ground wire in the trunk coming off the harness.

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Old 05-17-2010, 03:53 PM
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77 TRASHCAN 77 TRASHCAN is offline
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My car had a intermittant brake light problem. The left side brake would work most of the time. Every once in a while, the left sides would not work.

This is from when the car was NEW!!!
Do you think the dealer could figure it out, when it was under warranty???...

My car NEVER blew a fuse though...???

About 3 years ago I was driving it (car in signature) to work, one of my co-workers, noticed the LH brake lights out.........a couple of days later a small amount of smoke came out of the column, it stopped when I turned the ignition off, did not smoke again, although the LH brake lights NEVER worked again.

I tore the car apart, as suggested above...looked and looked for a short, physically followed ALL the wires through the car....

The final fix ended being, replacing the turn signal switch, yes the brake lights go through the T/S wiring....

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Old 05-17-2010, 05:00 PM
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If it was the dome light, it would blow every time you open the door right.

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Old 05-17-2010, 10:52 PM
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I had the same problem on my 68 GTO conv. It wound up being the turn signal switch. After I replaced the complete wiring harness in the column it took care of it. Mine had gotten corroded over the years and quit making a good connection. I had already replaced all the sockets for the bulbs and made sure all the grounds were in good shape. Maybe this will help.

  #7  
Old 05-18-2010, 11:20 AM
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My 79 Bonne would blow the interior light/brake light fuse but my problem was in the radio wiring harness. (I would lose power to the radio at the sime tome).
Found a bare wire.

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Old 05-18-2010, 07:02 PM
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Does it blow the minute you step on the brake and every time?

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Old 05-18-2010, 07:03 PM
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Don't forget, it does not have to be a ground to blow a fuse. A loose connection can do it as well. A loose connection is a high resistance connection, I have seen it happen before.

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Old 07-09-2010, 05:43 PM
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Just thought I would post what I found. I thought it was the dome light wiring, (on same fuse) but it wasn't. It was the trunk light socket. I don't even have a bulb in there. But finally realized the fuse popped, whenever the trunk popped. I just disconnected the trunk light(since I didn't use it anyway) and the problem is now solved. Just wanted to share. Thanks, Mike

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  #11  
Old 07-09-2010, 06:15 PM
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Thanks for the update.

Electrical gremlins are the worst.

Someone can use this update in the future.

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