Trailer Lights Do Not Work with 1998 Ford Explorer or 2007 Ford F-150 but Do Work w/Other Vehicles

Question:

I have purchased several products from you folks and it is a pleasure dealing with you. My question concerns my kayak trailer. The wiring kit I purchased from you for my RAV4 works great with the trailer as does my connection in my GMC Sierra. The trailer does not work with either a 1998 Ford Explorer or a 2007 Ford F150. In both instances the left light works fine, brake, turn, and flasher but the right side does nothing. Is this something to do with the Ford products? Does not seem to be an issue with the grounding since it works with the Toyota and the GMC. Appreciate any insight you can provide on this very strange issue

asked by: Ben P

Expert Reply:

There isn't anything unusual about the 1998 Ford Explorer or the 2007 Ford F-150 that would cause the right side trailer lights to not work. there are some things you can check though to determine if the issue is indeed on the vehicles or on the trailer.

First though it is possible for a trailer to work fine with one vehicle but not another even if there is no problem on the vehicle or trailer. What can happen is if there is a dirty or corroded trailer connector, some tow package wiring harnesses are able to still work and others cannot.

So the first step I recommend is to make sure the trailer and vehicle connectors are clean and free of corrosion on the insides where the wires attach and on the pins. If you are using an adapter make sure it, too, is clean inside and out.

It is also possible that there is a fuse and/or relay that needs to be replaced. You can find them easily using the vehicle owners manual. To further test the vehicle side wiring you can follow the help article I have linked.

It would be worth checking the trailer just to be on the safe side. The main connector grounds should be attached to clean and corrosion free bare metal surfaces.

The light grounds should also be attached to clean and corrosion free bare metal surfaces. If there is anything between a light ground and the metal trailer frame or if the trailer has an aluminum frame, tilt bed, or folding tongue, any of these things can interrupt the ground. Running jumper wires from the light grounds to the main trailer connector ground can help.

expert reply by: Michael H