F250 Trailer Charge Dead

[Naper]

I have a 2017 F250, trailer charging from the 7 pin connector is not working. The fuse (30 amp #27) is good. Cant find the relay no mention of it in the owners manual. Trailer lights and brakes work.

[LyleRussell]

I had the same issue. My Ford dealer went nuts finding what was wrong but eventually came up with a service note on it. There is no voltage on the truck pin unless there is a load on it. That's done so we don't short out the truck battery if snow or water gets into the connector. To prove this is correct measure the trailer battery voltage when disconnected. Then connect and start the truck. The voltage should be higher on the trailer battery.

[Al and Missy]

My 2006 F150 had a relay, at least it had a spot for a relay, but it was not installed. I bought the relay and my trailer charge port became active (but only when the engine was running).

On a lark, I dug up the manual for the 2017 F250:
http://www.fordservicecontent.com/Fo...ngEnabled=True
Fuse 27 says it powers the trailer tow charge relay
Item 37 is the relay

Maybe Canadian trucks are different



Al

[Naper]

[QUOTE=LyleRussell;1867959]I had the same issue. My Ford dealer went nuts finding what was wrong but eventually came up with a service note on it. There is no voltage on the truck pin unless there is a load on it. That's done so we don't short out the truck battery if snow or water gets into the connector. To prove this is correct measure the trailer battery voltage when disconnected. Then connect and start the truck. The voltage should be higher on the trailer battery.[/


Thank you.
The truck connector wouldn't show power on a meter or a 7 pin test light. I am thinking it needs some feed back voltage to activate.

[LyleRussell]

Naperville that's the exact experience that I had. Try my test. It's true of 2015 and newer. There is a fuse but it was installed at the factory. The relay is now built in.

Try my test to see if I'm right.

[LyleRussell]

Naper sorry about my autocomplete function.

[Naper]

Yep you are correct. Plugged in to the truck started the engine and sure enough it was charging. It would be helpful if Ford mentioned this in the owners manual.