my trailer lights still don't work! Help

Thanks guys, great advise. I think its a bad ground in the car. they attached it to seems like power coated metal on side of trunk?

I, myself, would not trust that ground.  Remove the screw, sand the paint off, apply a little dielectric grease between the ring terminal & the car body & re-insert the screw snugly.  Should do the trick if it is a ground issue.

I, myself, would not trust that ground.  Remove the screw, sand the paint off, apply a little dielectric grease between the ring terminal & the car body & re-insert the screw snugly.  Should do the trick if it is a ground issue.

That! - dielectric is most often found in a tube under the name of Ox-Gard.

Or Tune-Up Grease at places like Auto Zone.  Sometimes they even have it in little "single-serving" packets at the checkout for a couple bux or less.

Thanks guys. Just went back to rack and road they tested the confection 100 times and also scraped the ground things are working on the car end. It must be the trailer.

Check the ground on the trailer too.  Same applies to not grounding on a painted surface.  Beyond that ....  It's like Chevy Chase .... Gotta check it one bulb & connection at a time.

Are the lights on the trailer H.F. brand?  They are BAD about having crimp connections inside the lite housing that are poorly done, loose and cometimes just twisted together with no crimp at all.

How is it grounded? Through the hitch or through the trailer plug?