Hello all. Just bought my first Super Duty about a month ago and love it! (Prior trucks were a 1997 Ram with a Cummins and a 2003 Duramax) The new truck is an F250 Platinum Ultimate, SB, Crew. It has the push button start, which may be important information to answer my question.

My question is about the Auxilary power for the center pole of the 7 pin connector. The Dealer has no clue, and I read the manual and it doesn't offer any help either. I added the fuse (I believe it was a 30 amp in the #17 position under the hood) and assumed it would provide power anytime something was plugged in like my other trucks. That is not the case. Through trial I have gotten it to work but the sequence seems VERY strange and is not very user friendly. Here is what I have to do to get power:

1. Back truck up to the trailer.
2. Shut the truck off.
3. Connect the trailer plug.
4. Lock and unlock the truck (or wait a couple minutes)
5. Restart the truck with the trailer plug in.

It will then have auxilary power. This is especially annoying because I use it mostly for an electric tongue jack. I have to plug the trailer in first, go through the restart/lock process and then unplug the trailer and plug in the tongue jack (the truck doesn't power it up If I plug the jack in first). It took some time to figure this out, and I'm glad it works, but it is really annoying!!

Does the "smart" key have anything to do with this and is there a way to make the auxilary pole constantly powered? The truck has the upfitter switches, so that is an option, but didn't want to cut the factory trailer harness if I don't have to.

Any insight would be greatly appreciated! Thanks -Eric

 

The truck has to be on or running for the relay to activate for the power, but also being a smart controller it also has to detect the trailer, probably the resistance for the brakes to activate the charge circuit i believe. shouldn't have to lock unlock, just hook up the tt, turn truck to accessory the you can use the tongue jack. I didn't think any fuse had to be installed anymore on the '17's.

 

Regarding the center pole on a 7 pin......isn't this reverse anyway?

 

I believe indeed it's the reverse

 

I believe you have to tap the brake once connected and truck must be on

 

oo didn't catch that, yes the center pin is reverse lights.

 

Thanks for the replies!

I wasn't sure about the fuse, so when I couldn't get it powered, that was my first thought. Sounds like I didn't need to do that.

I will try tapping the brake with the trailer plugged in. That would make it a little easier. It sounds like no matter what, I have to take the extra step of connecting the trailer and then either restart, put the key in "accessory" or tap the brake. In any of those scenarios, it requires an extra step back to the cab to power up the accessory terminal before I can use the tongue jack.

From the time I first posted I went out to the trailer which is attached to the truck. The trailer is an enclosed hauler and I simply wanted to open the door, turn on the interior light and grab something. The light wouldn't work. I started the truck with the remote start and still no light! I had to go over to the truck and press the start button for it to power up the interior trailer lights. That REALLY sucks since I do that quite often. Looks like a constant power upfitter switch is going to be my best option.

This is just about the only complaint that I have with this truck (oh, and the horn that is always beeping at me when I walk away with the truck running and the key in my pocket!). The seat belt alarm was really annoying as well but I did the delete process and am much happier!!

 

Sorry- didn't mean to say center pole . It is the accessory terminal.

 

All 2017 F-Super Duty vehicles equipped with a factory trailer brake controller (TBC) utilize
a trailer module (TRM) which initiates the trailer charging system. For trailer charging to
operate, the TRM must detect a trailer is connected and a brake pedal input before
charging will be present at the trailer connector. Adding the trailer battery charge relay and
fuse into the battery junction box are not required to operate trailer charging with a TRM.

 

This is a Ford programming thing, as you have found out, either shut the truck off, hook up and start the truck or leave truck running and tap the brakes. It's meant to protect your batteries from running down on power without the truck running.

The other wrinkle this causes is if your checking your trailer plug with a tester. You have to plug in the tester, hit the start button without starting(no foot on brake pedal) so that it goes into full accessory mode.

 

Sounds like the wire should be cut and wired through a relay to ignition power! What a dumb system.

 

Sounds like a hack for FORscan. Power on ok. Tapping the brake, not so much.