Ford typically leaves it in the glove box from factory for the owner to install...Mine was installed at factory due to having the Max Tow Package
Switchover to Lithium
- Thread starter EBKRV
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Now, the trailering module doesn't allow 12V to go to the 7 pin unless it sees a combo of a battery load and your foot on the brake pedal so they now just install from the factory.
The problem with this setup is if you need a constant 12V at the 7 pin which I need for my electric over hydraulic controller. Of course the wire is a 16 or 14 awg wire at the 7 pin so it can't really deliver much current without a ton of voltage drop.
Supposedly, Progresssive is going to change how it works but not sure if they have done that yet.
My Hydrastar pump uses power from the on board LFP battery. Can't imagine relying on the 12v supply from the truck to power the pump.
IIRC the minimum wire was #12 with #10 or #8 recommended. (25 to 40 amp circuit)
If you have a DC to DC converter the alternator charge voltage will not change the output of the converter. It may change the input current however. Just don't think you are going to supply your 30A DC to DC converter through the 7 pin. You will need to run a 4AWG or 6AWG wire back the the bumper and run it to the trailer through an Anderson connector or equivalent.
I have read it has been changed to a 2 stage 14.6 then 13.6 power supply. I don't like it.
On my boat trailer, I don't have a nice big battery to supply my EOH which was the big problem.
Actually thinking of adding EOH and disc brakes to my travel trailer. I use the Titan EOH on my boat trailer and was looking at the Hydrastar or the Dexter.
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For me, I rarely do anything but drycamp so its not really an issue. When I do have shorepower, I typically just turn off the battery and let everything just run off the converter and the battery doesn't even see any charge.
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On the new trucks?
When I worked at the trailer place 7 was on a 30A fuse I thought? Or is that just the 250 and 350s and/or cab’n’chassis? Big wire is what I saw but that was as couple years ago
It's tiny. In this picture I am holding a 16awg wire next to the orange wire which is the 12V on the 7 pin in a 2018 f150
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On my travel trailer the break away system is powered by the house battery. I believe it was done that way from the factory. Less complicated wiring and if the 12v stuff in the trailer is working my breakaway brakes will too.
totally agreed...that's all trailers with electric brakes. You need some sort of battery to operate them in case of breakaway. The 12V+ power line from the 7 pin would do nothing for you if the trailer broke away.
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My 2011 and 2018 150 were both 30 amp fuses with that small gauge wire like Bruce has shown above...I can't recall what my 250 wire gauge was but it was also a 30amp fuse as well
On my 2017 F-350, fuse 27 for the Trailer tow battery charge relay is 30 amp. The F-150 has a smaller alternator so I could see where the same fuse on it is only 25 amp. But I would check the fuse specification chart in the owner's manual and then verify that by looking at that fuse in the fuse box.
Alternator has nothing to do with that fuse size.
Depending on the model, the F150 could actually have a larger alternator than the F350
No, but if you have a puny little alternator I could see the trailer battery circuit limited. However, given how Ford has been consolidating parts between the F series trucks I would be surprised if it's not a 30 amp circuit on the F-150.
Well...I just looked at my owners manual, OEM service manual, OEM wiring manual ....and the fuse in the fuse box...all 25A
My alternator in my 18 F150 is 200A....yours?
397 amps, but that's dual alternators.
12VoltInstalls
life passes by too quickly to not live in freedom
keeps the banjos playing though
When I hear banjos I know it's time to GTFO.
30 amp is really pushing the limits of the standard plug used by rvs. 25 amps is probably a more reasonable number.
No doubt. A post on the Ford Truck forum indicated that the wires were a limiting factor to how many amps/volts you could expect the trailer battery to see. I don't recall the voltage drop but the amps didn't get much above 20 amps. This was on a truck with the OEM dual alternator/battery setup.
The limiting factor is the wire size. The F350 likely has a much bigger wire than the F150 and it makes zero difference what the alternator size is.
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