Charging RV batteries with tow vechicle

[Russell_Clifton]

Have any of you folks installed the necessary wiring and components so you can charge your RV batteries while you are driving? It looks like it would be easy to do, the most expensive part being the heavy gauge wire running from the tow vehicle engine compartment back to the trailer.

If you have done this, was it worth the investment and time? Thanks

[milo]

Russell...if you'd stated it was an F-150 in your original statement, you would probably have been given that info at the start that the fuse & relay is in a bag under the seat & where to put em.

[carl2591]

Second and third that... 🙂

much better way to charge moving or not.. that along with the 7 pin will get you back charged in no time. a nice solar package can get gotten for almost the cost of a good honda generator.

one good 285 watt 24v panel and a morning star PMW? charge controller will do the trick on most RV's batteries with NO noise or gas, spark plugs, repairs etc..

smkettner wrote:
Solar also works while driving on a sunny day.

[Rbertalotto]

The biggest draw I find on my batteries is the furnace. Propane heats it but that fan draws quite a bit of current. I have a #10ga wire from the trick to the battery in the truck camper. Will put a bit of a charge in the battery after driving a few hours, but does not charge it 100%. I added a 120w solar panel and that really charges the battery while driving even on a rather sunless day.
When boondocking for a few days, if there is no sun or my battery use is high, I run the Honda generator for a few hours. This year I'm adding another 120w panel on the roof. For $150 it is the least expensive route to more juice.

[SoundGuy]

Russell Clifton wrote:
Have any of you folks installed the necessary wiring and components so you can charge your RV batteries while you are driving?

You certainly want a charge line but presumably you realize this TV > trailer charge line (Pin 4 on your Bargman connector) isn't designed nor is it capable of "recharging" a significantly depleted deep cycle battery but rather is there simply to maintain as close as it can to a full charge on the trailer battery as it's being drawn down by the trailer's parasitic draw and anything else you may be running at the time, such as the fridge, so you don't arrive on site with a depleted battery. :W

[Tvov]

When we first bought our TT, I was using an '87 F350 dually dump truck temporarily. I had the dealer setup the hitch and wiring harness. I just assumed it charged the battery - since the salesman said the TT battery would charge while being towed. When I switched trucks, I found out that the tech at the dealer never bothered to run a charging wire. The trucked I switched to was a used 2000 F250, and it was all setup correctly with the charging wire.

My present 2008 F250 came with everything connected and active.

So, yea, you should double check that your truck is setup for charging.

[YC_1]

That is great. Posting your vehicle and rv model is helpful too. Did you measure the voltage at the RV batteries themselves with the truck running? This way you will know the wiring is complete.

[Bedlam]

Many truck camper people upgrade the charge wire on their trucks to help the camper battery. Most will also install a constant duty solenoid triggered off the ignition so their truck battery is not drained if the charge wire is left connected while camping.

[Lynnmor]

A guy in our club was on his fifth trailer before a RV dealer pointed out that the brake controller fuse was still in the bag in the glove box. As always, read and follow directions.

[mowermech]

I guess it really DOES pay to read the instructions!

[Community Alumni]

Moved to Towing forum

[Community Alumni]

Well I guess different vehicles have different systems. The truck/trailer combinations that I have towed all had working charging systems.

[Russell_Clifton]

Well,well well. Isn't this interesting. After hearing all you folks saying it should be working, I found this tid-bit on a forum.

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.

Sure enough they were in the glove box, and I installed them in the fuse box. Leaving for Alaska April 28th. Thanks for the help!

[wanderingbob]

Most trucks are wired to charge as you drive . Some will require that you install a fuse under the hood . What kind and year truck is it ?
No heavy wire is needed for most of us . I drive 3 or 4 hours a day and then dry camp and have plenty of power in my pair of 6 volt batts .

[Blue_Hill]

I have a 2011 Chev truck and was surprised to find that the truck, factory wired with a trailering package, didn't have the wire hooked up to the 7 pin. The wire was there and I found on the Internet where to find the wire, and the stud to hook it to in the fuse panel under the hood as well as the location where the fuse needed to be installed. It took a special fuse, 40 amp, I think. I'm not sure of the reason for running the wire, but not hooking it up, but it wasn't hard to find the information on the web.