1999 Santara Class CShakedown cruise yesterday went well, but revealed an issue with the coach battery. It should charge when the rig is plugged in to shore current, right? The indicator lights in mine showed a partial charge when we arrived, but when we left it was down as low as it can go. When I got it back home, it looke a little healthier.Shouldn't 12 hours of being plugged in to shore power bring this back to full? I'm thinking that the drive home charged the coach battery off the truck alternator, but the unit isn't recharging off of shore power. My thoughts so far:-- maybe the converter isn't working right and all of my 12V activity in camp was draining the battery. -- maybe the battery is the problem, and it isn't taking a charge. The service records I have from previous owners seem to indicate the batteries are about 3 years old, which is about all we get here in southern Arizona. But the fact that it seemed to charge up off when driving isn't consistent with this. Any other possibilities? Trouble-shooting I can do before I haul the thing off to an expert? Rich

Hi,Measure the house batteries voltage with a meter. Then plug into shore power. Measure again, and if you are not seeing well over 13 volts there is a problem.If this has happened, until you can get the rv into a shop use a stand alone battery charger to fill up the house batteries.

Yes, it should have charged. Did you have the battery cutoff switch on, or off?

12 hours probably won't bring it back to full. It depends on your converter. Many RVs come with a Parallax converter that charges at a very slow rate. I agree that it seems to be charging from the alternator so it should also charge from the converter. Check the voltage as pianatuna suggests and make sure your battery disconnect switch is not on storage as Snowman suggests.

Trouble shooting this will be more complex because there's no AC at the storage location, and my HOA board is VERY snarky about parking it here anywhere I can get at AC.@Snowman, the switch has two positions. In the "Store" position, all 12V services are disabled. In the other position, I think, is labelled "on." I have it in ON when I'm using the RV or traveling, and "STORE" when I'm not.

Hi rich,Borrow a medium size inverter, or generator for testing the system.

Battery charging issue | Good Sam Community

rich85704
Explorer
Mar 29, 2014
Welp, I don't hear a noise when I turn the battery disconnect from "Store" to "Use," but the 12V lights go off when I put it in "Store," and I've taken that as evidence that it's working. Is the "clunk" noise made by the solenoid which Dusty refers to?

I have a general question here -- how do you trace a wire which goes down one rabbit hole and up another? Rely on the color of the wire?

Rich
Bordercollie
Explorer
Mar 29, 2014
Your engine's alternator is properly charging house battery while driving.
Your converter cabling to the house battery may not be making good connections or the house battery disconnect switch/relay may not be working properly,
(you should hear a snap or clunk when you turn the house battery disconnect switch on and off coming from the battery compartment. If those things are OK, the converter's charging circuit may not be working. I just replaced an OEM converter that was boiling out batteries with a modern PD 9245 converter that works very well.
Replacing the converter is very simple

All batteries need periodic checking of electrolyte levels and adding distilled water when needed to keep the plates covered.

http://www.progressivedyn.com/prod_details/rv_conv/rv_converter_pd9245c_2.html
pianotuna
Nomad III
Mar 29, 2014
Hi,

Check the reverse polarity fuses on the converter output.
Dusty_R
Explorer
Mar 29, 2014
Most mh have an electric selonid/relay that connects the engine charging system to the house batteries. With the ignition switch it run position, check check for a difference between incoming power from alternator and outgoing to house battery, if there is a difference check for 12v power at that energizes the coil on the relay. If you have 12v there then that relay is not working.

Dusty
tenbear
Explorer
Mar 28, 2014
Makes sense. Now check the output voltage at the converter, and if its 13+v find out where it disappears. If the converter isn't putting out check the vac into the converter.

Edit: A fully charged battery should be 12.6-12.7v. Your battery at 13.7v probably had a surface charge that would leak off in time or when a load is applied.
rich85704
Explorer
Mar 28, 2014
The latest developments. I took the battery out; it was pretty depleted (a little more than 10VDC). Charged it until my charger said it was full. Took it to AutoZone whose checker said it was at 13.somethingVDC and "good battery." Took it back to the rig, reinstalled. Voltage across the battery terminals when installed, 13.7VDC. Voltage across terminals with truck engine running, 14+ VDC. With the generator running (output is about 128VAC) the voyage across the battery terminals is 12.8. Aha?

All fuses checked, all breakers checked.

Look like the problem is either the converter or cabling from converter to battery. Supported both by measured voltage and the fact that the rig's battery checker showed a much happier batter after the brief drive home from my shakedown cruise.

Make sense?

Rich
Snowman9000
Explorer
Mar 27, 2014
I had that same battery switch in my B+. It's part of an Intellitec brand battery control system. If you set that switch at Store, you won't get any charging.
maillemaker
Explorer
Mar 27, 2014
Check your HOA rules. With ours, we just aren't allowed to park for more than 24 hours at our house. But obviously you can pull your RV into your driveway for when you are packing for or coming home from a trip!

You will only need 30 seconds to find out if your converter is charging your battery or not.

Plug into shore power, then put a volt meter across your battery terminals. When charging, you should be at 13+ volts.

Alternatively, I assume you have a generator? Run it. You should see the same results as being on shore power.

I have heard that not all converters are fantastic battery chargers. They may or may not charge your battery, and if they do, they may do it slowly, and they also don't always pay attention to the condition of the battery and may over-charge it.

But anyway, a volt meter at the battery terminals will tell the tale in less than a minute.
pianotuna
Nomad III
Mar 27, 2014
Hi,

Add a modest solar system. That will return the battery bank to tip top shape.
rich85704
Explorer
Mar 27, 2014
I have a block diagram of this rig's electrical system, so that's where I'll start tracing. I think what I'll do right away is remove the house battery and bring it home, where I have a charger and can see what the battery's condition is and bring it up to full charge.

Getting it checked under loan at AutoZone or some such is a good idea, and easy to do here.

My plans has been to take the rig for a drive every week or so during the "season "for a number reasons, one of which is battery health.

Storing it where there's AC just isn't in the cards right now.

Forum Discussion

Battery charging issue

About Motorhome Group

Related Content

Battery Charging Issue

BATTERIE/CHARGING ISSUES

Battery Charging Issue

Battery charging

battery charging