brake wiring 7 blade to 7 pin.

[v8only]

My truck is 7 blade, trailer is 7 pin.

What i did was buy 6' of cable with a 7 blade end, and put a 7 pin end. Now i have crossed all my wires so that all my lights work but i am having two issues:

1. With all lights off, brakes etc i have 2 running lights on, with no source of 12V going into the trailer. I have gone around all 7 pins to see if i can find a source and i cant. (it could be that im not getting a good ground but i dont think so)

2. I am not getting power to my drums.

any ideas on where i should go?

Thanks

 

[Smallplot]

First thing that comes to mind is wires touching inside one of the ends to the 12V power "hot" plug or just have wires switched in your cable. Make sure wires go to the correct pin plug end as they correspond to the blade plug.

Make sure wires have not been switched and not in the "standard" place indicated on the plug ends. Use a test light and check the function of each blade on the truck wire connectors to match back to trailer. Plull the trailer plug apart and make sure each function (or pin) corresponds to the correct supply side pin (12V to 12V, LT to LT, Ground to Ground, etc...) Dont rely on wire color trace the wires on your trailer to make sure what each color goes to.

 

[Tractor Seabee]

There is a an adapter for your situation, saves hanging up all the extra cable. Fits right in the 7 blade socket. I bought one from NAPA. There is an adapter for all the different configurations from 7 blade. I borrow trailers so have quite an array. If you research on line you will find the DOT standard(s) which car and truck factory harnesses are configured to. Many times I have had to re-wire a trailer connector to match that standard so I can tow with my factory wired truck.

Ron