Travel trailer towing question

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Daveb65

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I have a 2015 expedition with trailer tow package. I just bought a travel trailer and the expedition pulls like a dream. My question is the charge circut for the trailer battery. There's no power coming from the plug to the battery. Owners manuall does not mention a charging circuit for the trailer. Does anyone know if there is one and where to find it. Any help would be greatly appreciated. Thanks!
 

chuck s

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This is relay controlled and the ignition must be on (engine running). On the back of the truck it's Pin 4. Check for 12VDC there before going too much deeper. Ignition must be On. If that's hot check the trailer's umbilical cord to the battery.

I vaguely recall having to fit the relay with an earlier Expedition or Explorer. Relay and fuse was furnished with the new truck so look for a zip lock bag in the deep recesses of your glove compartment or that area under the rear floor.

On my '07 it was Fuse 42 (10A) and Relay 13 (30A) and I think they were in the box over the radiator. On my '17 I can't find any reference to trailer battery charge so it's probably part of the OEM trailer brake controller.

There's a long thread from back in '07 that may help. I think there are (were?) photos in it.


erting-4-pin-trailer-7-pin-bargman-7-pin-connector.png

Pin 7 (Aux) is wired to Backup Lights on every Ford I've towed with. Few campers have them but a set of PRC fog lights and 25' of wire to your rear bumper are worth the effort. Even if you never back in the dark they let the tailgaters know you're backing!

-- Chuck
 

chuck s

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Sometimes it's just that simple. "Daddy, is the switch On?" :)

Don't depend on the truck to charge a deeply discharged battery, though. The truck's voltage regulator only supplies enough voltage to trickle charge the battery to replenish what was used to start and run the electrical system in the vehicle. Disconnect the trailer battery when in between-trip storage or the propane detector and stereo memory will suck the battery dry in a couple of weeks just sitting there.

-- Chuck
 

1997SCEBFEX

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I put a water proof trickle charge adapter into the battery box for extended no-use periods. beat taking the cover off every time.

also, if your tt is equipped with the brake safety plunger and lanyard, don't pull the plunger while storing as it too will set the brakes and run down the battery also.
 

chuck s

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Trickle charger will work but ensure it's not boiling the battery dry. This was common in the past but it seems the later chargers are smart enough to not do this. Also be sure it's putting out the full 13+ vDC. I had one that only put out 7 volts (!) and it drained rather than charged my boat battery.

But, if like me, you have no access to shorepower when parked between trips disconnecting the battery should be done. As simple as a switch (I have a marine (boat) weatherproof battery switch mounted to the outside of the plastic battery box. Cuts the Negative (-) post.

-- Chuck
 

rollinstone

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In my neighborhood I have to store my batteries (two 6V GCs) in the garage between trips. Damn tweekers!
 
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