Trailer turn signals do not work.

[mep1811]

I have a trailer (M416) lights issue and am at a loss how to resolve it.

When hooked up to my FJ-60, 7blade RV to a 4 pin trailer using an adapter I do not get any turn signals.

When the trailer is hooked up to another vehicle, 4pin to 4 pin the trailer lights work perfectly.

When my FJ-60 is hooked up to a different trailer , 7 blade RV to 7 Blade RV, the trailer lights work perfectly.

When hooked up the FJ-60, I have tried three adapters with no luck. The harness is new on the trailer.

I had a 7 blade RV plug but rewired it with a 4 pin.

The trailer lights never really worked right but in troubling shooting this, there were two bad vehicle

grounds. I changed the trailer harness because the old harness was beat up and patched in places.

The only thing I can think of is to change the trailer harness back to a 7 blade RV.

Any suggestions ? Thanks in advance.

 

[mep1811]

lights

I decided to have the truck side wiring harness removed and a new 4 pin harness installed. I took my truck to U-Haul so they would be on the hook if things did not work. While I was there, I saw this module that powered the trailer lights off the vehicles battery and not the vehicle harness. The guy at U-Haul said that some older vehicles have weak electric systems that can't fully power trailer lights.

Everything works perfectly now.

https://www.uhaul.com/MovingSupplie...le-Wiring/Trailer-Light-Power-Module?id=13612