Brake light not turning on?

2008 FORD F-250
167,000 MILES • 6.2L • V8 • TURBO • 4WD • AUTOMATIC
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GUSTAVOJR21
  • MEMBER
  • 1 POST
The brake light where my roof is won't turn on when i press on the brake but the LED lights around it does. i can't find the problem.
May 10, 2024 at 8:19 PM
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STEVE W.
  • ✓ASE Certified Mechanic
  • 15,200 POSTS
  • ASE Certified Mechanic
That truck uses an independent circuit for the CHMSL lamp. There is a fuse (12) and relay in the junction box under the hood that turns that light on. It also has stubs that go to the trailer harness and the OE brake controller. The first item I would check would be the fuse. I have seen the trailer harness wiring corrode and short out and blow the fuse. If it is good and the relay is working, then I would test the wiring at the lamp itself as well as the lamps.
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May 11, 2024 at 3:41 AM
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