F-150 Charging TT battery while towing

This came up when a friend of mine realized that his F-150 was not charging the camper battery while he was traveling. Here's what we found out. Ford does not ship their trucks with the ability to charge a camper battery while towing. Why?? It's our guess that they are concerned with having a 12-V hot wire going the length of the vehicle and it's only being used by those pulling a camper. Here's what they do. All F-150's are shipped with a plastic bag shoved somewhere inside the truck, door or glove box storage. Inside the bag is a fuse, wiring harness with a plug and a relay. The relay goes into slot #9 in the main under hood fuse box just behind the radiator. The fuse, 30-amp goes into slot 21. The wiring harness is used if you don't have the factory installed brake controller.

Here's the real kicker. The dealership had no clue about the situation. At first I was told that it was up to the camper place. Since it came from the factory with the tow package installed harness, plug, etc. that idea didn't wash with me. Since they didn't know about the plastic bag with the stuff and we both purchased our trucks for pulling a camper it's my guess that many Ford owners who do pull campers don't know that they may not be charging the camper battery when they are towing. Our trucks are 2010 and I don't know what years may be affected. If you have a factory towing package check your owners manual, locate a relay slot marked, "Trailer tow battery charging." If the relay is missing then you are not charging while towing. Don't forget the fuse as well. It is marked the same.


TeJay

Re: F-150 ChargingTT battery while towing

Thanks for the information - I will pass along to friends with the F150s. Certainly makes one go "hmmmm"........ Not what I would have expected.

Brian

Re: F-150 ChargingTT battery while towing

TeJay said:

The dealership had no clue about the situation.

TeJay

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VM

I would insist that the dealer contact Ford and find out. They certainly have the ability for a quick response from Ford. I think I would find a more responsive dealer My truck keeps the batteries fully charged while traveling with the refrigerator in the propane mode. i did order the dual alternators, trailer and camper options for my truck which supplies a lot of axillary power. However, I think all F350's with the trailer option supply power to the 7 pin connector charge line.

Re: F-150 ChargingTT battery while towing

This is a safety issue. You need the trailer battery charged for your emergency disconnect trailer braking system to work.

Re: F-150 ChargingTT battery while towing

Its been that way for years but I never found a dealer that was not aware of it. I'd be looking for another dealer.

Re: F-150 ChargingTT battery while towing

Thanks TeJay. Going to look at my manual now. Great information. Thats what i get for asume something. Biker Bob.......

Re: F-150 ChargingTT battery while towing

My truck has Factory trailer tow package and Factory brake controller. I checked my Fuse/Relay box under the hood. Yes both my Relay and Fuse are there in right place. Does that mean my Battery is charging while i`m cruising down the highway? Thanks again for the imformation.......Biker Bob

Re: F-150 ChargingTT battery while towing

You can check if the trailer is being charged by pressing the test switch on the panel while the truck is idling and the lights will be all on including the C for charge. I do it when+ever the truck is hooked on the trailer ready for the trip, while trailer unplugged from the 110/220. It has to work to have fully charged batteries when stopping and for emergency brakes

Re: F-150 ChargingTT battery while towing

Your comments about finding another dealer were correct. When I was looking at Fords we went to the dealer that had a better selection of trucks. That was my mistake. I should have looked then ordered from the one that I do business with now. Actually my new dealer was the ones that gave me all the information concerning the problem discussed. I went to the original dealer because I thought that they'd have a bag with all the goodies that I needed but all they had was a relay. From what I understood all F-150 trucks and perhaps others are shipped with the stuff in a bag in the truck but they are not installed. If you get 20 trucks a month you should have 20 plastic bags of stuff and that's why I went back to them.

TeJay

Re: F-150 ChargingTT battery while towing

I would kind of wonder if this "bag of goodiies" only comes with trucks including the towing package option and not ALL trucks. If the vehicle manufacturer can save 10 cents on each vehicle they will do it.

Re: F-150 ChargingTT battery while towing

If you have a new vehicle with the tow package installed there are several paths this might go. The truck, if equipped with a towing package will come with the plastic bag of goodies (relay, fuse, short wiring harness). It probably won't come with the brake controller but it should. The relay and fuse are not installed because Ford does not want the vehicle to have another hot wire going the length of the truck and stopping at the trailer connector unless they know that a trailer will be hooked up. Once the truck is sold it is now the consumers problem if a fire starts because of the hot wire (LAWYERS YOU KNOW).

A good dealer should install the fuse and relay or at least tell you and show you about it so you can install it when you do get your camper. My first dealer knew I was buying the truck to tow a camper. The truck was on their lot equipped with the tow package minus the factory brake controller. They installed the controller but told me nothing about the fuse and relay. My friend who was the one that brought this issue up called me a few days later and while preparing for a trip found the bag of goodies. The dealer told him what he needed but never mentioned that it actually might be in the truck. Neither one of us use that dealer for anything except to tell people where NOT to go to buy a truck. This dealership is the premier Ford truck dealer in this part of the state. I find it remarkable that this issue has never come up at that dealership before. That's information that every salesman should know especially if they are trying to sell truck for towing.

TeJay

Re: F-150 ChargingTT battery while towing

Will have to check this out. I have a F-150 2011 that has trailer package w/brake controller all installed at factory. I have towed my trailer 6 different times now. Hope batteries are charging.

Re: F-150 ChargingTT battery while towing

As caissiel said when your vehicle is connected and running check the panel in the camper and it should indicate that the battery is charging. Most of us never think of doing that because when we are connected and ready to go we are usually locked up and ready to go. That's the easiest way to check. The other way is check the camper battery voltage not connected or TV not running then check it running. The open post voltage (OP) (voltage when a battery is not being charged by any outside source) will be around 11.9-V - 12.6-V's. When charging by TV or converter it will be 13.5-V to 14-V's.

The OP voltage of a battery is subject to temperatures, usually lower when it's below freezing, or if you've had to crank your starter a little more than usual. The charging voltage has to be at least 1-Volt higher than the OP voltage to force electrons into the battery.

So now you know the procedure for checking either TV or your converter charging condition. Those are two simple checks to assure that all is well with the charging situation on our campers.

TeJay

Re: F-150 ChargingTT battery while towing

Thanks for the info TeJay.