Trailer lights no work

[HotrodR]

Neither the flat plug or 7 blade plug has tail light power. I removed and checked continuity on every fuse with trailer labeled on it. I think 29 is for trailer tail? Turn signals work, hot prong has power. Any thoughts?

 

[jejb]

Have they ever worked?

 

[chopperman1]

Check the connector under the rear bumper.

 

[ramffml]

You have to use a multimeter or a 12 volt probe light to check whether you're getting voltage at the 7/4 pin socket. Don't ground your probe/meter on the frame, use the ground in the harness/socket.

If you're getting voltage across all pins, then the problem is in your trailer.

If you're not, then all I know is that there are multiple fuses for everything so check carefully. I recently blew the fuse for my right trailer signal. The left trailer signal was on a separate fuse and was working fine which left me scratching my head until I figured that out. And the signals are on a separate circuit/fuse from the running lights (IIRC) so again, just open the manual and really double all the fuses.

 

[HotrodR]

It worked fine for a few months.
Checked all the suggestions, thanks. The fuse that I believe powers the tail light doesn't have voltage on either blade in the fuse block when I remove the fuse, fuse tests ok.

Off to the dealer, it has a recall to deal with on the ECU anyways.

 

[crash68]

The fuse that I believe powers the tail light doesn't have voltage on either blade in the fuse block when I remove the fuse, fuse tests ok.

Did you check for power at the fuse with the running lights on? The power for all the trailer lihts goes through a relay then the fuse, so it's not hot unless that circuit is "on".
There's a wiring diagram floating around this forum on the trailer wiring, I'll see if I can find it if someone else doesn't post it first