7-Way Trailer Wiring Harness Stopped Working On a 2011 Honda Pilot  

Question:

Helpful Expert Reply:

The first thing I recommend doing is checking the vehicle side connector for dirt and corrosion build up at the 4-Way. I had a friend that had this problem. The 4-Way had enough corrosion in it to cause the lights not to work. After clearing it out, it worked fine.

You could use a circuit tester such as # PTW2993 if you do not have one to test the wires at the back of the 4-Way to determine if the signal is getting through to that point. That would confirm a problem with the plug, most likely corrosion.

If the wiring also does not show the proper signals, then it is likely that there is a blown fuse or bad relay that you will need to replace.

If fuses are bad you will only need to replace them with the same size. Do not use larger or smaller rated fuses. They must be the same as the ones that are present. If changing the fuses does not help then there is probably a bad relay that will need to be replaced. You will need to visit a Honda dealer to get the correct relays. An auto parts store may be able to match them but they have to be exactly the same.

expert reply by: Michael H

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