Can we charge TC battery with 7-way?

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OTRA

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We have a 2008 Travel Lite TC and an F 150 with heavy-duty suspension and it works great.  We have never connected the camper battery to the truck battery to charge while driving.  Is there a way to do that?  Can we use the 7-way? 

THANKS!
 

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Yes, look up the standard for 7 way plugs and one lead is power from the TV.  Here is a link.
http://www.etrailer.com/faq-wiring.aspx
Your trailer is probably already wired right. Your truck is already probably wired right.
Check with a multimeter on the trailer plug. It should show 12 volts with the battery hooked up there.
Check with a multimeter on the truck jack. It should show 12 volts there with key on.
If the truck does not have power, check to see that lead is connected in the plug, and that it has a fuse or breaker, and it is not blown.

 
Thank you for your reply.  I don not understand how to hook the 7 pin to the camper battery...  The wiring diagram showed which blade I need to connect to.  Should I take the cover off the plug and hook a wire to the proper screw and then to the battery?
 
If the 7 pin plug was wired right, it is done. just check that pin for 12 volts now with your battery connected to the trailer normally.
If it was not wired right then you may have to open up the plug to fix that.
Then check the truck jack with key on.
 
I don't know if Ford's are the same but GM products have the wire hooked up at the 7 pin but the end at the fuse block under the hood is not hooked up.  You have to cut it loose and put the eye on a stud on the fuse block and install a fuse.  Hope this helps some.  There are also a couple good forums for Ford and GM pickups that show this stuff.
 
I charge my battery while driving around sight seeing using a seven pin plug. I attached a hot wire and a ground
wire to the plug and secure the battery in the bed of the truck.
My question is about over charging using this method.
Will the truck alternator regulate the charge or will the charge on the battery slow down the charge as the battery reaches 80%?
 
Rick

The truck alternator is regulated so overcharging isn't ordinarily a problem.  In practice because of the wire sizes and lengths the TC battery tends to charge somewhat more slowly than we might like.
 
For the charge line you will want to run 8ga wire to the battery and have a 40amp fuse and an isolator wired in line. The isolator keeps the camper from draining the battery of the truck when the engine is not running which is important.
 
Or just unplug the camper from the truck when you stop for the night, then plug it back in when you leave in the morning.
 
An easy way to check if things are wired correct.  Unplug the 7 way.  Measure voltage at the trailer battery.  Now connect the 7 way and start the Truck/TV engine.  If the voltage increases then things are probably wired correct.  If the voltage does not increase then there is a wiring problem or a fuse missing. 
 
We all have our methods.  I have two batteries in the truck, separated by an isolator relay.  One is connected to the 7-way.  It adds more battery capacity, and since I don't have room in my TC for another battery, that helps.
 
A week or so ago when I bought my new Northstar TC800, the guy at the RV center stated that Tundras and Fords (when using a dealer-installed 7-way Trailer connection) are wired so that all you have to do is plug in the 7-way coming from the TC (my Northstar already had a 7-way connector, but I don't know if this was dealer installed or came this way from the factory) and this would charge the RV battery whenever the truck was running.

I hope this helps.

RickRV
 
Here is a simple way to see if your system is already connected.  With trailer connected and the truck engine off check the voltage at the trailer battery terminals.  It should read about 12.6 volts.  Now start the truck engine.  Wait a couple minutes then check the voltage at the same place that is the trailer battery terminals.  It should read higher than it did before (13.0 or greater) you started the engine.  If it does you are all connected correctly.  I have found due to the long wire distance this does not do very well in charging a discharged trailer battery.  But it will keep a charged battery at peak charge while towing.
 
Just a sidelight to the discussion, some MH's have power already routed to the 7 pin connector. (black wire, 1 o'clock position) This can be used for charging a toad etc. Sometimes, people fail to put a diode (one way electrical valve) in the circuit when they wire up to their toad battery. Without the diode, the 12 volt power from the toad battery can flow back into the MH and on certain makes/models it will allow the engine to keep running despite turning off the key! Monaco brand MH's specifically will do this, others may.

So, if you wire up your new toad and then can't turn off the engine of the MH, now you know why.

Ken
 
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