Have Ford Questions? Ask a Mechanic for Answers ASAP
Welcome, I'm Chris (aka Moose) I prefer to work when others don't, I am here around lunch and after dinner till after midnight.
Can you follow the instructions in the links below.
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You can open the harness to trace the wire to find the brake or open the harness to find the wire and overlay a new wire to the next splice.
If there is an overlay already there then the plow headlights have been spliced in there and that is likely where the issue is.