I have a 99 f450 it's blowing the trailer turn signal and break lights fuse with no trailer hooked need help
Most likely the wiring on the back on of the truck is shorting out, check to see if you find any open wires behind your tailights or near the trailer light plug.
I will do that. Once before I put a fuse in that was bigger than the one it calls for do think that I may have burn a wire. When I put a fuse in now the driver side trailer brakes and singal will only work for a few mins before blowing the fuse again the passenger will sometimes last a few hours and sometimes even a few days
well putting a bugger fuse will sometimes cause a short but its not likely it has to be a bare wire shorting out the fuse ive seen this many time start from the back and work your way forward check for any loose wires and then check if they have been rubbing on something overtime rubbing will cause the wiring to get damaged and cause a short.