Trailer brake lights

[GH1]

I'm having a problem with my trailer lights. With the vehicle lights off, the trailer lights work as designed, but with vehicle lights on I don't have trailer brake lights. Runing and turn signals work fine. Vehicle is a 2009 4 cyl with factory 4 flat harness. Any help will be appreciated.
Thanks
GH1

 

[4x4junkie]

That sounds like the ground wire going to the trailer may be open.
Check the ground connection on the truck side of your connector... If it's good there, the problem is probably somewhere on the trailer.

I've dealt with similar issues with trailer lights not working (or only partially working) myself, and almost always it's been something to do with the ground connection.

Hope that helps

 

[GH1]

Thanks, I'll check it out.
GH1

 

[RonD]

Yes, +1

When trailers lights aren't working correctly there are two Rules
Rule 1: Check ground
Rule 2: see Rule 1

Repeat as needed