Trailer Wiring Replacement Recommendation for 2002 Mercury Mountaineer

Question:

I have a factory tow package installed but the relay box in the rt. 1/4 panel is missing the wiring that the relays should plug into. The plug at the hitch is a 7 plug round and the harness is factory stock. verified by dealer Have you ever run across this before and how can I fix this? I have power for running lights but no blinkers, brakes, or backup lights. The Lights all work when hooked up to an alternate tow vehicle with a flat 4 plug, the problem is we want to upgrade to a bigger trailer that has brakes.

asked by: PAUL R

Expert Reply:

You can try to track down the wiring issue that you have through the factory wiring or you can bypass it all and go with a kit that allows you to not have to track down the wiring gremlins you are having.

I'd recommend installing the part # 118344 to give you a new 4-way and base for your trailer wiring.

Now if your trailer does not have brakes all you would need is the part # 37185 as an adapter to convert the 4-way to a 7-way.

If you do have trailer brakes you would need the # ETBC7 instead of the # 37185 and a brake controller. This kit comes with everything needed to wire up the 7-way and install a brake controller.

For a brake controller I would recommend the Prodigy P2 Brake Controller part # 90885. This is our best selling brake controller because of how well it works and how easy it is to setup.