Truck won't charge trailer battery

Doughoff · 09-07-2009, 10:39 AM

I ahve a 2004 titan with tow package and small travel trailer with refer. When towing and the refer on DC the trailer battery goes to below 11v. the out put of the trailer plug reads 14v when the trailer is unpluged and truck running, but when the trailer in connected it drops to around 10v if there is any kind of a load. at the truck battery it still reads 14v. Is this all wiring loss?
Any Ideas?

**Carbeaux** · 09-07-2009, 11:05 AM

Probably is. I don't know off hand what kind of amperage the hitch plug on our trucks is rated at.

Also consider that our alternators are in reality only adequate under loads. They put out enough to keep a stock truck going but have only a minimal cushion beyond that load. I've not ever had a problem with mine though, and it's run trailer lights and the refer simultaneously.

Doughoff · 09-07-2009, 06:03 PM

Thanks for the reply.
We have recently driven for several hours on more than one occation, after starting with a full charge only to find when we reach our destination that the trailer plug in electronic volt meter is reading down below 11v and the battery is definetly depleted. The battery is in good shape and holds a charge as one would expect when the refer is back on gas and batt recharged.

**4mula1fan** · 09-07-2009, 06:05 PM

Something isn't wired up right....

Shane06fl · 09-07-2009, 06:23 PM

Something is not wired right or pulling to much draw from the 12vdc system. The refer runs off of gas when not hooked to shore power and the only thing 12vcd does is work the solenoid and ignitor to allow the gas to flow and ignite.(assuming you have a electric/gas refer) Not much of a draw there. Lights, exhaust fan and other gadgets pluged in will cause a draw also. A bad battery on your rig will also over work your trucks battery if your running more than the trailer lights.

Things to check:
Ground at the battery
The Battery
Ground at the converter

To be honest, it sounds like a bad battery, a bad ground or both.

Learjet · 09-07-2009, 08:54 PM

If you have a 3-way frig and run it on 12 volts, that 12 volt heating elements pulls a lot of amps and your truck will not keep up. Run the frig on propane while traveling.

Doughoff · 09-08-2009, 08:49 PM

What is standard practice about traveling with the gas on? It just seemed like a good idea not to. The fridge does draw 15 amps on DC so it could be the wires from the truck relay to the plug are too small for the load.

**4mula1fan** · 09-08-2009, 08:52 PM

I did some digging on that, seems a lot of people travel with the fridge running on gas. I didn't think it would be a good idea, but it seems it is common practice...

Doughoff · 09-08-2009, 08:59 PM

Running on the LP seems to be the simplest solution for now.

**4mula1fan** · 09-08-2009, 09:06 PM

I'm chicken! I can just see my camper in a ball of flames going up for a relaxing weekend...

Learjet · 09-09-2009, 06:41 AM

if you are paranoid stay home and never leave the house

If you are not paranoid, do like most folks and run the frig on propane. That is what they are designed for. With proper maintenance of your system, that includes checking the propane lines and connections for leaks and chaffing, you will have no problems.

BK19702 · 09-14-2009, 10:20 AM

I have a three way fridge, run on propane all night before we leave so it gets cold, then keep it on propane until we get to the campsite. You can travel with the propane on for your fridge, just do the proper maintenance as Learjet mentioned. One safety note: make sure you turn the LP bottle OFF before you pull up to the pump to fuel up. When you pull away from the gas pump a safe distance, put the bottle back in service. I know some people who don't even bother with this step, but that's on them.