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Q: Electrical issues. Brake lights won't go on. Replaced fuse but still keeps blowing.

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My brake lights weren't working, so I replaced the fuse but it kept blowing. All of a sudden, all the power to my dash died and some times when the stars are aligned it will work. I'm trying to get it running agin since it is my only ride. Would it be a relay?
My car has an automatic transmission.

A: Hi, thanks for writing in. Whenever a fuse ...

Hi, thanks for writing in. Whenever a fuse continually blows, you have a short that needs to be located. You stated the power on your dash died and followed with your still trying to get it running. With this I will assume the truck is not running and the dash lights are part of that problem. When all the power to a vehicle disappears, this is usually a product of wiring branching directly from the battery. There isn’t one relay that powers everything on your vehicle. Relays can’t handle that much current.

A test light is the best tool to locate such electrical problems. If my assumption is correct and you have lost power to everything, you will need a wiring diagram and a test light and begin testing near the battery. If some systems are still working, I would trouble shoot where the short is to the brake lights. Do this by studying an electrical diagram to locate all that that fuse powers. Then one at a time, disconnect the suspected components until the fuse stops blowing. It is very useful to use a circuit breaker when doing this. That way you won’t need to replace the fuse after it blows each time.

If you still need help with this, I recommend the following inspection to help you out. [https://www.yourmechanic.com/services/electrical-components-are-not-working-inspection)

Good luck!

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