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Trailer tail lights not working

8417 Views 8 Replies 6 Participants Last post by  Poppy
I rewired my PWC trailer about a year ago and all was working fine until last night. The brake lights and turn signals function properly, but when I turn on the headlights the trailer lights do not stay lit. The brake lights and turn signals still work when the headlights are on, but the trailer is blacked out at night until I brake or put a turn signal on. Any ideas what might be wrong?
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Check for a loose/coroded ground connection and or tail light connection.
^^^Agree with the above, maybe in the light socket itself. I've run into this before. Also, do you have a ground wire that comes from the light socket and grounds to the trailer frame?
Thanks for the quick responses. I have a ground at the front of the trailer as well as one for each tail light. I usually only drive about 10 miles with the trailer to the ramp, but about a month ago I drove from Johnson City, Tennessee to North Florida, so maybe the bumpy highways jiggled something loose. I'll keep you posted. Thanks again.
I just checked the wiring and all seems fine. The ground on the trailer is clean and is in contact with the metal and the same goes for the tail light grounds. I'll tinker some more, but probably just end up replacing the wiring. Time to go to Wally*World.
Have you checked the wiring @ stricktly the 4 pin trailer connector comming off of the vehicle. The lone pin is ground. Check it with head lights out. Also with the headlights on.
If the brake and turn lights work the ground should b OK.
What trailer connector do you have?
The running lights are on the green wire for a flat four wire connector. Turn on the running lights to see if there is voltage on that wire from the vehicle. If so, there is a problem with the trailer...connector or wire going back to the lights.
I replaced the wiring over the weekend and all is working fine. Before I replaced it I hooked up to my neighbor's trailer and the running lights were working, so it must have been something with the green wire. Thanks for the tips. :)
Thanks for posting the final solution; I'm glad that you got it working properly.

I marked this thread resolved, and closed it.
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Thanks to all who helped in this thread.
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