Have Ford Questions? Ask a Mechanic for Answers ASAP
Welcome, I'm Chris (aka Moose). Thanks for allowing me to help you for a much lower fee than a dealership.
Is this a truck or van?
Do you know the fuse number?
Does it blow immediate when the lights are turned on?
Fuse 18 goes the brake pedal switch and the indicator flasher relay in auxiliary relay box 1 behind the left side of the dash. This fuse powers the light green/red wire. Your looking at a most likely wire short here. I recommend starting by looking at the brake switch for chaffed grounded wiring.
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