Right turn signal not working with trailer connected

I’m having some problems with my right turn signal with a trailer connected to the factory 7 pin connector of my 2018 Tacoma.

The turn signal flashes briefly and then stops. If I wait a few seconds and try it again, if flashes briefly again and stops. If I don’t wait, it does not flash at all. It’s like the truck is detecting a fault and disabling the signal. The same is true of the right tail lights on both truck and trailer with brakes or flashers.

connecting a different trailer to the truck works fine. Connecting the trailer to a different truck(dodge) also works. And the truck works fine without the trailer.

Anyone seen this kind of thing before?

 

Sounds like there is an issue with the trailer. It working on a Dodge does not mean the trailer is fine.

 

I’ve seen similar but to my masonry table saw. We were working at this one house (house is newly build, about 5yrs old, 20A outlet), our masonry table saw would trip the breaker and it doesn’t matter which outlet we plug it in. All other heavy duty tool works fine. I asked the neighbor to borrow their outlet to test, it works fine. Bring the saw to a repair shop, they said nothing is wrong. I ask the shop to go to my job site and they were surprised but couldn’t figure out why. The saw still works many years after, even when plugged into a 15A outlet, it didn’t trip any breakers at any of the house we work at.

Sorry for the long reply and couldn’t offer much help. But I suspect a fault in the wiring of trailer’s right side. Do some diagnostic yourself. Disconnect the light and test with a different light. Get some new wire and test with a working light. If all of those fail, maybe the 7pin connector of the trail is bad?

 

Thanks guys, you were right, it was the trailer. The right turn signal wiring was shorted to ground hard enough that my truck was going into over current protection. The Dodge Power Wagon was just tolerating the short. The trailer dealer is going to address it.