Hmmm. I have to get my trailer in a month, then I will be able to help. By the pictures above the light orange, bigger wire, looks like the 12 volt accessory power. If that's an 8 gauge or 10 gauge wire, Ford has planned to provide plenty of current. The problem may be sensing the load, and how much it can release. I too rely on charging both trailer batteries going down the road, so, depending on how this ends up working, I may do th Aux6 40 amp mod above. I will be able to measure current and voltage. It's been helpful to read, setting up the trailer, and pressing the brake to initiate or use the slider to initiate braking.

 

I can't see that the wood cause any issue as you would be cutting the wire, so essentially taking it out of the system. Just as long as you cut the wires in a place that ensures you are past the smart system.

 

yeah those were my exact thoughts..

 

Once I get my new truck, I will be seriously considering this as I don't want to guess or hope that my trailer battery is being charged. This seems like a stupid system from all that I have read on it.

 

It would be interesting if someone put an ammeter in that circuit to see how many amps is being provided.

 

You guys should consider approaching this like many of the truck camper folks do: run a heavy guage independent charging circut to your camper. The problem is you will never get enough power through the 7 pin to really charge your camper batteries.

I have done this on 2 super dutys so far (my 06 and now my 16). You run a pair #2 or #4 copper cables from one of the truck batteries, though a circut breaker, through a heavy duty 12v contactor, and then to a heavy duty 2 pole plug mounted in the truck bed. I use the Phillips 100a electric liftgate plugs and have one on my truck and one on the front corner of my slide in camper. I then use a semi truck coil cord made by Phillips to go in between.

Works great. Have seen up to 60 amps at 14.1v going to the camper when the refer is running in 12v mode. I still have the 7 pin providing power as well, but dont expect much from it.

My 06 had dual alts but by 16 doesnt. On the 16 I just swapped the oem 200a alt for a DC Power 270 amp alt. Produces 200 amps at engine idle.

 

I'm just going to add here.
I was able to operate the front landing gear to lift my 5th wheel trailer off the truck with no batteries in the trailer
It has a 2800lb pin weight.
It didn't lift fast, and I had to stop three times because it was too much load for continuous running ...but it did lift it. I don't know how many amps it takes but I'm sure it is a large load.
If youre familiar with the system it is Ground Control 3. It is fast and geared low, I know it's a power sucker.
I find it hard to believe the tongue jack of a TT can't get enough power to even run.
There is either different systems in different trucks or some grounding issues with some of your tongue jacks.

 

I just went to pick up my 5th wheel from the dealer after a little work. Taking the trailer to the dealer last month was the first time I used my new '17 F350PSD to tow. I go to pick it up today and the trailer battery is stone dead. We hook up the chord, no landing gear. I look for a wiring/circuit breaker/fuse diagram online as I forgot to put the owners manual back in the truck the other day. I got lead down the same path looking for a Trailer Charge Relay and Fuse. I owe Frantz an apology for an "I'm irritated" msg I left him on his VM.

I just got home and found this thread. It appears that the system in the 2017 SD is very different than in the past. I assume that my old truck, a 2015 SD either operated differently or it worked the same as this new 2017 but I never noticed the difference.

I hate all things electrical when it comes to troubleshooting and modding as to me it seems to involve a bit of black magic and voodoo!

So...if I understand this correctly:

1. The '17 does not use the "Trailer Charge Relay". Trailer Charge is handled via the smart system whatever the heck that means.

2. There is only enough current to provide a float or possibly a trickle charge. In my case with a dead trailer battery the "smart" system will not give much of a charge unless it has may hours of being hooked up. It may even require some power on the trailer battery before it will begin providing charging.

3. Just plugging the umbilical chord to my truck will not provide the power required to run the landing gear or the stabilizer jacks. Grrrrrrr!

4. In the past, there was enough current available to actually run the refer unit via the umbilical chord off the Super Duty's huge alternators/electrical system. I have to admit, this is what I thought I was going to be able to do. I thought that's how it worked with my '15 SD and I think it's how we used to do it when we towed the old camper (a travel trailer) with the wifes 2010 Expedition.

5. If I want to run any high load camper stuff off the Super Duty's electrical system I'm going to need to mod the truck, possibly via the up fitter switches. I really don't like screwing with things electrical especially on a brand new truck.

Any other leads to associated threads dealing directly with this stuff as it applies to the 2017 SD's would be greatly appreciated.

 

You are correct on points 1-5.

If you want adequate power to your trailer then you would need to run a new larger gauge wire to the 7 pin plug's Aux Power post.

 

I noticed the same problem when I first hooked up my trailer. After some research I squeezed the trailer brake controller manually on and that powered my 12V to the trailer right up. Powered the electric tongue lift no problem. No need to cut anything or run any wires.

 

What year is your truck? If it's a 17 then you must be running the jack off of the trailer battery not Ford's charge circuit

 

17 just got it last week. No battery in the trailer. Running off the factory 7 pin power.

 

Then Ford must have redesigned the circuit. They started with the "smart charging "circuit on the '15 F150s. My '16 F150 had it as well as my'17 F350 that I got last fall. I haven't tried it on my '17 F150 yet that is 3 months old

 

Sounds like Ford may have changed the system on later builds, but as to earlier builds like mine, you are correct on all five points. But it is an easy fix. I ran a 10 gauge fused wire from a positive battery post to the back of my truck and put a pigtail on it. See first picture. Then I cut the appropriate wire on my trailer plug and put pigtails on both ends of the cut wire so that it is returned to its original configuration when I want. See second picture. When I want to run my fridge in my RV on the inverter, I plug the trailer end of the splice in to the pigtail on the truck. Just finished a 1,000+ mile tow and ran my fridge the whole way. Been running it that way since November. No problems.

 

Do you guys have a three way refrigerator? As far as I know, mine is two way. It only runs on 120v ac or propane.

I sure wish my refrigerator would run on electric power while the truck is connected.