Tow vehicles - Ford struggle

Blueespy

We had a 2019 t@b 400 that we initially pulled with a V6 Jeep Grand Cherokee. No issues. Switched to a 2020 Ford F150 5.0 and immediately had issues with our Norco Fridge (DC/AC/Propane). On DC while traveling within a few hours, we would get low DC error codes. Upgraded to lithium but same issue. Short investigation and we learned it was our FORD. The Ford computer limited power through the seven pin to just enough for the brakes and lights. I know that sounds crazy but that was the issue. From the forum here we learned about a DC-DC converter. Got one and it took about an hour of me supervising my son to do it. After connecting the seven pin between the Ford and the 400, we connected the DC-DC cable from the converter to a power line running from the Ford battery. Problem solved. The DC-DC kept the batteries charged.

Just upgraded to a Haven 220 and 2026 FORD and thought (my mistake) that by 2026 Ford would have recognized their mistake and fixed it. Something told me they hadn't so I had the dealership install a DC-DC when they took delivery of our Haven. My son installed the Ford portion. First trip I forgot to turn on the DC-DC power from the truck so when we stopped and tried to turn the A/C, nothing. Check of the batteries through the app showed low power, just enough for the fridge, lights, brakes and exterior lights. I switched on power, drove for about an hour and stopped at a rest stop and tried the A/C. Worked perfectly, so for "us" and I say "us" as I think our Ford issues are specific to newer models, we need the DC-DC to charge our "house" batteries properly.

SLJ

A three way fridge uses a lot of current when on DC. Maybe more than the charging feed from the tow vehicle. We have a 12 volt fridge so there is low current draw with plenty left over for charging while towing.

My new 2025 Ford Ranger with the basic tow package charges the batteries and easily runs the 12 Volt fridge when towing in tow/haul mode. In fact, if the batteries aren't switched on in my camper I get a notice on the driver's display that the trailer batteries aren't charging. When the Ranger is off it automatically disconnects the charging feed so I don't have to unplug the seven pin like I use to have to. I can also stand behind the camper and test the trailer lights with the Ford app on my phone. That's a plus when there's no one else around.

BillCB

I'm towing my 2024 T@B 400 with a 2025 Ford Maverick with the 9 speed transmission and tow package. No issues with charging tho' there is a recall because of a defect in the Trailer Module which might cause brake and signal lights not to work. I have not had that problem but a modification will be applied in a few weeks.

Blueespy

https://tab-rv.vanillacommunity.com/discussion/comment/221387#Comment_221387

I can do the brake light test as well which is a cool feature. I run it from the info screen in the Ford and check the lights as I do a final walk around before rolling out. I agree, the three way did use a lot of current on DC. The Haven and the DC fridge are nice and if I just wanted to keep the fridge running, I wouldn't need the DC-DC, but the seven pin doesn't seem to keep the batteries at full charge if I wanted to run the A/C. It is strange.

SLJ

https://tab-rv.vanillacommunity.com/discussion/comment/221388#Comment_221388

The Maverick w/4K tow package only has a 400 pound max hitch weight. You're over that pulling the 400 with it.