1988 Chevrolet Van Repair Question
Start by replacing the fuse with a 12 volt light bulb such as a brake light. Then you can unplug things to find which ones make the light go off or dim indicating the short is removed from the circuit.
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i blow a fuse only when i turn on the headlights
What fuse is blowing?
tail lps 20 amp
Do you have a trailer wire harness? Check that make sure it isnt pinched or rubbing on something causing a short to ground.
no what else could it be
Like carradiodoc stated, your going to have to make a short checker, get yourself a wiring diagram and start unplugging bulbs etc. circuits/ and anything on that circuit, It is a process of elimination to find a short/ It will take time and testing. Anybody can guess at it, but it is you that is going to have to do the testing. I cant locate a good diagram for you, maybe one of the other guys can find or post one.