Turn Signals Do Not Work With Epicord 7-Way Molded Trailer Plug with Junction Box

Question:

I recently installed this Epicord 7-way trailer plug with junction box on my remodeled 1972 Shasta 1400 travel trailer, which will be towed by my 2013 Ford F150. My problem is that I cannot get the left and right stop light/turn signals to work. Ive installed all new fuses and relays in the truck, Ive also checked to make sure that all ground connections are good and ensured that the bulbs in the new tail lights are working. The running lights work, but the stop lights and turn signals will not work.... The F150s trailer plug receptacle has a diagram on its cover which clearly illustrates the specific function of each blade by its location. My question is: do you have a diagram which will similarly illustrate the epicord plug-end which will show me the function of each individual blade and its specific location, not by the wire color? This is the only way I can possibly confirm that the plug and receptacle blades and their functions match up correctly. The wire color and their coordinating functions that are mentioned on the Epicord 7-way Trailer Plug products web page only tell me where the junction box connections are. It does NOT tell me where each of these colored wires go to which female blade connection on the actual trailer plug, so that I can ensure that they are correctly matched up with the truck plug.......I hope Im making sense here. Thanks in advance for your assistance!!!

asked by: Sharon J

Expert Reply:

You do make sense but there is not a diagram showing the blade functions of the Epicord 7-Way Molded Trailer Plug with Junction Box # 277-000141 because it shows the wire colors by function. So the intention is to make it simple by showing you what wires on your trailer you need to connect to the junction box.

While I do understand you thinking it may be the plug not matching up, that's highly unlikely. I know you said you checked your grounds but do the turn signal lights ground via mounting hardware? If so and and mounting surface is aluminum that may be the issue; try connecting a wire to the light studs and grounding them to the trailer frame.

What about the connector on your 2013 Ford F-150? Have you checked that for corrosion? Oftentimes something simple like that can be the problem so I strongly recommend taking a look at your truck connector to see if there is any corrosion that may be hampering the connectivity. It will be green or white and you would need to clean it out or replace your 7-way with (assuming it is the factory 7-way) with the Mighty Cord Replacement 7-Way RV-Style Trailer Connector for Factory Tow Package # A10-7072VP.

expert reply by: Kyle S