i plugged my rv trailer in and i have basically no lights. the only thing i have is one brake light and nothing else. i know it is not the trailer because i have plugged it into another vehicle. i checked all my fuses, where do i go from here? which main fuse or relay could it be? why would i get one brake light and nothing else? no park lights, no running lights, no turn signals?

i have a 2002 f150 bifuel 2wd

 

did you check you wiring harness thats where i had a problem with my 03 the stock wiring only has like 18 gauge wiring and it breaks quite often

 

where did it brake? where do you check it? is it above the spare?

 

if you have the tow package start checking your wiring from the 7way thats mounted on the bumper all the way to where it joins the rest of the wiring harness for the truck easiest way to do this is to us a multimeter or a test light with someone in the truck turning on each of the light systems one at a time another posibility is u just need to clean out your truck plug and put some di-electric grease on the plug to prevent corrosion. anyways i hope this helps

 

I just hooked up my boat for the first time to my '03. The two rear trailer lights were slightly lit. I looked at the 4-way connector on the truck and saw that one slot was completely green. I rolled some sandpaper and cleaned it slightly. More lights worked on my next plug-in. I'm going to really attack it all tonight with some steel wool and cleaner if needed, then dielectric grease to keep it from happening again.

 

I had the same corrosion on the four pin but couldnt really clean out the one set inside the plastic. The seven pin connecter works fine so I just keep a seven pin adapter in the truck for trailers that have four pins