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Brake Light Fuse Blows

Lil Jack

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Lil Jack Enthusiast

Lil Jack

Posted
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Ive got a question hopefully someone can help me with. Everytime I push the brake, my stop fuse blows. I have changed the brake switch, unhooked the wiring harness for the cab brake light underneath the dash, unhooked the tail light/brake light connector at the rear bumper, checked the wires all along the frame rail and still cannot find the problem. The fuse still blows when brake is pushed. Any suggestions would be great!!!

 

Mike

Nytemare Senior Enthusiast

Nytemare

Posted
Posted

Sounds like you may have a bad connector. Cut the wires off, and place a light on the end of the bare wires, push the brake and see if the fues blows than. I am thinking you are sinking all your voltage to ground through one or both of your light sockets.

 

 

Since current (I) is voltage divided by resistance...and resistance of ground is basically 0 ohms

 

I=12V/0Ohms...that means Infinite current.

Lil Jack Enthusiast

Lil Jack

Posted
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Im not sure what connector to cut off? I have the truck sitting with the cab brake light harness unhooked under the dash, the tail lights unhooked at the main connector by the rear bumper and a new brake light switch installed, the only reason I put a new switch in was because their cheap, I opened the old one and it seemed ok. Still when I touch the brake it pops the stop fuse. No lights are currently hooked up to the brake system. All the wiring running in the frame rail seems fine, Im not sure whats left to check? Any help is appreciated.

Mike

Nytemare Senior Enthusiast

Nytemare

Posted
Posted

I was thinking of the bulb socket, but you've eliminated that already.

 

There has to be a relay in the system somewhere, have a look around, there should be another relay in the truck like it, so just swap it. See what that does. Although, relays don't usually fail like this, you never know.

Lil Jack Enthusiast

Lil Jack

Posted
  • Author
Posted

After a third check of everything I possibly could think of, I decided the only place left unchecked was the short stretch of wire tucked up in the frame by the gas tank. I droped the tank and thankfully found the problem. A previous owner must have had tank work done and someone must of pinched one of the two yellow brake wires and repaired it with only a butt connector. It had come apart and was shorted to the frame. Problem and wire repaired, brake lights working. Thanks for the response Aiden, on to the next little fix of a 13 year old truck.

Mike

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