Left Turn Signal Not Working on 7-Way Trailer Connector at Rear of 2005 F-250 Super Duty

Question:

the turn signal lights work on the truck but i dont have blinking on the yellow wire going to the wire harness for the trailer what do i look for.

asked by: Joe M

Expert Reply:

On your 2005 Ford F-250 you'll want to start by testing the 3 O'clock and 9 O'clock pins on the truck side connector with a circuit tester like # PTW2993. Clean the pins free of any corrosion. if you're not getting signal there, use the tester and test the wires coming out of the back of the 7-way along the harness. Keep an eye out for any kinked or damaged places on the wiring that could be causing the issue. If you're still not getting anything, then you'll want to check for a blown fuse.

If there are no issues along the wiring, you'll need to test the connection point that the 7-way harness plugs into on your truck. You will want to make sure both the harness side and truck side of the connector are clean. If you find the problem to be on the truck's connector that the 7-way plugs into then you'll either need to check the wiring of your truck or take it to a mechanic to look at.

expert reply by: Charles S