For some reason the tail lights don't work on my boat trailer. I have brake lights and turn signals, but no tail lights. My back up lights don't work on my truck and I recently found out that I need a new neutral safety switch to correct the back up lights issue. Could this also be the reason I do t have any tail lights on my trailer? All fuses are good, and trailer had tail lights working up until about the time I noticed I didn't have back up lights. Also know it's not a ground issue. I'm a little stumped on this one. Any advice? Thanks.

 

What year is your truck? Have you checked for power to the running light pin on the truck's plug? I doubt this issue has anything to do with the NSS issue.

 

Certain generations have individual fuses for each part of the plug. One for each turn, stop, and tail lights. Recheck your taillight fuse when a meter or circuit tester.

Also, have you checked the bulbs?

 

The truck is a 2004 F150 supercrew. I'm going to swing by store this evening and purchase a test light to see if I have power to that pin. I didn't think it would have anything to do with the NSS, but wanted to get other opinions. Thanks so much for your help.

 

Bulbs are good. Will test that individual pin with test light tonight when I get home. I tried connecting two different trailers....same outcome. All work except tail lights. My guess is no power to that pin. Thank you for your help!

 

Problem solved. After testing with test light and verifying not power to that trailer connector pin, I pulled the fuse and just replaced it. Turns out the fuse was bad, but very hard to tell by just looking at fuse.

Thanks to those who gave advise. Much appreciated. Lesson learned...even if fuse looks ok....try replacing anyway.