I’ve read a few of the threads describing the system. I do appear to have all of the fuses except those indicated as for non-brake controller vehicles (which would be expected). I’ve also tried every permutation of startup and hookup procedure I’ve read.

so - the catch - my horse trailer has a variety of accessory lights that run off of this circuit, but it does not have its own battery. with my prior trucks this has been fine because there is just a constant 12v+ on the black wire from the 7 pin harness. Does the Ford system anticipate the trailer having its own battery, and only supply charging voltage if it detects a battery? Can anyone tell me anything else that would be illuminating?

I’m prepared to add a battery to the trailer but would like some confidence the issue is related….


thanks! Pics because every thread needs pics…

 

I'm fighting the same thing. I have a 2019 KR with integrated controller. I haven't been able to get mine to work, but I have read that with the integrated controller the fuse and relay are not needed. The sequence to get it to work is have the trailer connected, door must be shut, apply brakes at least 1 time, and it should then supply power. Mine however still won't do that. Some said you must be moving, some said the door didn't have to be shut, and I read a few other issues. Whatever the reason, mine won't supply power back there at all, at least that I have figured out. I'm about to cut the wire and hook it up to an upfitter switch so I can turn on trailer charging. Or, put in a relay that feeds from the battery and comes on automatically when I start the truck. Kinda dumb for something as simple as power to the trailer.

 

The trailer must have a battery, the battery must not be current protected and the battery voltage must be above 11.3v for the system to work.

 

Woohooo, been fighting mine and just figured it out. Fuse #65 was blown. BUT, to make it work, the door has to be shut, and the key fob IN the truck. If either of these are not done, it turns off the charge. And I do NOT have a trailer attached, just a test light hooked up to the + pin at the bumper. Also, no trailer is selected on the dash. So, check fuse 65, make sure your fob is in the truck and the door is shut.

This is so dumb,,,,,, futher testing says the door can be open, but a foot on the brake and it will charge too. Also,,,, if you put it in neutral, you can take your foot off the brake, WITH the door open, and it continues to charge. So,,,,, it's safer to be in neutral, with your door open, than it is to be in park, keyfob in your pocket, while you are hooking up the trailer? And to top that off,,,, you can be in neutral, get out of the truck, with the door open, and the keyfob in your pocket, and it charges,,, but if you are in park,, it shuts off the charging with any of those things. Makes perfect sense right?

Passenger door doesn't change anything. I think the thought here is if you get out of your truck to hook up a trailer, it turns off charging so there are no sparks as you plug it in since your fob will be in your pocket. When you get back in, it will turn on charging. If you have an electric jack that needs power, you just need to leave your fob in the truck and shut your door.

 

I found another thread on this issue.

https://www.ford-trucks.com/forums/1...r-mystery.html

 

No sheeeet… fuse 65 was blown. Going to get one.

 

I bought the below and I was able to fool a 2018 and 2020 truck into thinking it was connected to a trailer. I was able to check the power feed pin to make sure power was available.

 

I made a video how mine works. Hopefully it will help explain the function a tad better. It seems a lot of people have issues with the way Ford designed it.

 

Mine works without battery. I was able operate all the lights and slides on my travel trailer with no batteries installed. Just the 7-way on the truck.

 

Agreed, see my video above. Nothing plugged in, other than a test light on the charge wire.

 

Now that my blown fuse 65 is replaced I can confirm… no battery required. Above explanation with the tester light is precisely how mine works…

 

There are some engineers at Ford with a perverse sense of humor. I can just picture them giggling as they came up with this goofy arrangement. Of course, identifying the wrong fuse supplying power to the plug is just icing on the cake. Probably a few beers involved and a cocktail napkin at the local bar. I imagine the discussion started off pretty straight forward and became more convoluted with each beer.