Trouble getting tow hitch wiring harness to work

2017 TRD Off road DC with tow package. I have a 5 pin on the trailer and i'm using an adapter to plug into the 7 pin. All i get are the reverse lights to work. Anybody having similar issues? I have trailer brakes.

 

Simply use a DVM to verify the pin out on the truck. If good,

Plug in the adapter and verify the pin out on it. If good,

Use a jumper and test each pin on the trailer to the adapter plug on the truck.

You have to isolate the problem. It can only be one of three things. Truck issue, adapter issue, trailer wiring issue.

 

I didn't think 5-pin connectors carried reverse signal? Left, right, brake, tail and ground. You want reverse, you need the 7-pin on the trailer.

Edit: Misread your post. Either way if your getting reverse lighting out of the 7 into the 5 through the adapter there's something wrong with the adapter or your trailers wiring.

 

Just for giggles- try cleaning off the terminals on your 5 pin with a shot of brake cleaner. Also hit the adapter, both ends. Let them dry thoroughly then test it.

Little trick that works for me almost 75% of the time when confronted with that issue.

 

4 and 5 pin connectors get there brake through the turn signal wires. So it's left turn, right turn, trailer markers (parking light) and ground. 5 pin adds reverse