Troubleshooting a 7-Way on a 2008 Ford F-250 that Has No Trailer Light Signals
Updated 04/01/2015 | Published 03/31/2015 >
Question:
I have no signal or brake lights at the 7 way plug but park lights work 12 volt charge has 12 volts trailer brakes have power. The truck is a 2008 f250 gas 5.4 with factory trailer wiring. What do I check? Thanks
asked by: Paul
Expert Reply:
First place I would check is all of the trailer wiring fuses and relays in the fuse box of your 2008 Ford F-250 as it sounds like you may have blown some fuses/relays. Beyond that you can check for corrosion on both sides of the 7-way connector and clean as necessary.
I attached a help article on troubleshooting trailer connectors for you to check out as well.

Product Page this Question was Asked From
Ford Replacement OEM Tow Package Wiring Harness, 7-Way (Super Duty)
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- No Converter
- Factory Tow Package
- 7 Blade
- Plug and Lead
- Plug-In
- Visible
- Tow Ready
more information >
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