Hi all

Long time reader first time posting. I have searched but haven't come up with an answer.

I have a 1999 ram 1500 with factory trailer wiring harness. I use a 7 to 4 pin adapter and get a full functioning trailer (blinkers and stop) but no park lamps or running lights.

I checked every fuse and they are all good. The 7 pin connector is new. I should have power on pin 6 (opposite pin 1) on the square plug, I have no power.

The truck has trailer brakes added but I know nothing about the installation.
The truck is new to me.

Any ideas?

 

You have to swap a wire in some of the adapters. Check package.

 

There aren't any wires coming into the 7 pin with power while just the lights are on. Turn on the blinkers or stop lights and you get power on various pins but nothing with just headlights/park lights

 

It seems that the big square relay/fuse under the hood marked trailer was partially blown. This makes no sense to me but all the light were working except the tail lights.

For kicks I swapped out the fuse/relay described above and now all is working well

hope this helps somebody