will an 06 f150 with the heavy duty towing package keep the battery on a travel trailer charged through the 7-way plug? and yes i have installed the relay that was included with the brake wiring. thanks

 

If you have it wired per the instructions, yes.

 

what instructions?.....all mine came with was where to put the relay and where to plug in the wireharness for the brake controller. i was told that the trailer was already set up for it and that i just need to make sure my truck was. called the local dealer where i bought it from and they were dumd-founded and didnt know what i was talking about. the relay says trailer battery charge but i just wanted to make sure. thanks

 

Instructions are relative...

You can check with a voltmeter with the truck running, you should see 12V on the terminal of the plug.

 

With the trailer plugged in, and the trucks engine running, you should see about 13.5v at the trailer battery..... At rest, the trailer battery would show around 12.8v in a fully charged state.

So, you are getting 'some' charge to the trailers battery while it's connected and the truck is running... It will take some time for it to 'fully charge' doing it this way, but it will charge...

FYI, when you shut off the trucks engine, the relay shuts off the 12v charge to the trailer, so you won't drain your trucks battery if you leave it plugged in and the engine off.

Mitch

 

Thanks Mitch, you're very right on the 13.5V and the relay purpose.

 

Unlike Dodge and Chevy...which can get a drained battery from just leaving a trailer with a battery/charger plugged in.

Thanks Ford..............

 

I have an enclosed trailer that I would like for the battery charge circut to remain hot all the time for charging of my airplanes in the trailer. I put a jumper in place of the relay in my 99 f150 so it would be hot all the time. Is there another way of having the charge circut hot all the time without putting a jumper in place of the relay. I don't like leaving the switch in the run position but I don;t wont to burn anything up either.

 

The relay acts like a switch so the charge line turns on and off with the ignition. It is still a fused circuit so you are protected from burning things up.
You could always run additional lines from the battery to the trailer, but I find that most people who do that forget to fuse those lines actually creating a fire/burn hazard.
Use a jumper and if you decide you need a switched ignition source you could always put the relay back in.

 

Your battery on the trailer may not be wired to charge it. On my horse trailer I bought, it wasn't. I wired it to charge off of the aux power. You just have to take a look at it and see.

 

On my 09, I had to add the relay and a cartridge fuse from Ford.