trailer relays

Thanks for all the info.  I switched out relays with ones I know are good and the problem still persisted.  I would guess the problem has to be from where the trailer wiring harness is connected to the vehicle wiring at this point as all the functions on the truck are working.  Could the problem with only one blinker exist with a bad ground?  I am wondering if I need to scrap the old trailer harness, get a new one, and reinstall?  It's a little frustrating that everything was working fine and now it's a problem.  Starting to wonder if I shouldn't just bring it back to the dealer.  And your right the Pathfinder technical specs are all pretty much the same at the Frontier.  Thanks for the help to this point.

Hate to say I told you so but do what I suggested a few posts ago, check/test back from the trailer plug to where the trailer loom connnects to the vehicle wiring.  This is auto electrics 101.  I don't  know why you keep going back to the relays,  I doubt whether they will ever go wrong.  In 40 years the only relays that have ever failed me  were lock relays by Kiekert on pre 92 BMWs and Porsche 928 and fuel pump primers on Ford and Porsche (2 and 1)