My coach sat for about 8 weeks. Went to move it and the engine battery was dead, drained, kaput. House batteries were fine, they were replaced recently with new deep cells. Anyway I used the bypass/boost switch to start the engine. There is a switch where you can designate the radio to run off of the house or engine. Should that switch be in either direction for a benefit or is it just to run the radio without having to turn the ignition on.The house batteries charge off the generator or engine but the engine battery just charges off the engine correct? I am charging engine battery now and will do a test to see if it has a dead or weak cells tomorrow. I did not have the coach on ground power while it sat, it's in my backyard and periodically I was going in and pushing the indicator switch to see how the house batteries were. Thanks....

The radio switch can be in either position to operate it. However the memory ids normally off the chassis battery

The engine should charge both sets of batteries when running. If not there might be a problem with fuses or solinoids between charging and the batteries. I also have a radio switch that is either travel or park so it can run off the coach batteries when engine off.

Paul, you are correct about the generator and alternator charging the house batteries. Using shore power is the same as using the generator, both feed through the Converter which converts the 120VAC to 12 VDC.You can use a DMM or an analog VOM to check for current flow, you do have to place the meter in series with the load to check for amperage. Some of the Better DMMs can read when in parallel but not all will.Normally when your chassis battery is good, it will be charged by the engine alternator and when it reaches a SOC somewhere around 12.6 to 13 vdc, it will then switch and charge the house batteries.You can check the BIC(battery isolator controller) and see when the two potteries are charging in parallel. The voltage going to the house battery will jump up to about 13.5 volts. It's really cool.I might add you can put a center off switch in place of the switch that allows you to use either the chassis or house batteries. That would eliminate the vampire draw of the clock and such.

One bad thing about the newer vehicles is Parasitic Drains that occur.I had the same problem with mine at first but neighbor,a retired ASE mechanic teacher,explained it to me. The only to stop it was to disconnect the battery when not in use for a period of time or keep it plugged in if you have a Birdlike I have or put a battery maintainer on it.

Another popular remedy that works well is the LSL Trik-L-Start (or its bigger brother, the Amp-L-Start). These little gizmos are DC powered battery charger/maintainers: when hooked in, they divert a little of the charging current from the converter (or solar, if you have it) to the chassis battery to keep it charged. They're not too expensive, easy to install, and work reliably.Of course, if you don't have anything to charge the house battery with, the chassis battery won't get/keep charged either with these devices.

Engine battery and house battery questions. | Good Sam Community

DrewE
Explorer II
Mar 23, 2016
burlmart wrote:

1) is constant trickling to 13+V better for batts?

2) does the GM 2005 chevy 6.0L have a live DC receptacle as standard (not RV builder) feature

3} what worries me most is could the DC receptacle cause some other dashboard lights/gauges/switches to blow a fuse?

1) Better than a slow discharge? Absolutely, positively, without a doubt. If in the vicinity of 13.5V or higher then keeping an eye on battery water level becomes increasingly important.

2) No idea. It's not too hard to find out by checking things.

3) No, not with any sensible trickle charging current. As long as your trickle charger is putting out no more current than the receptacle is rated/fused to power, you'll blow no fuses...and if you have that much current, over 10 or 15 amps, it's hardly a trickle charger anymore in my estimation.
burlmart
Explorer
Mar 23, 2016
my BIRD talk was mainly meant to point out that the chassis bat reduces about 0.2V per week. i am not aware of any radio or other parasitic drains, so i assume it is due to the engine computer.

but if i plug RV in to shore power and use a battery minder/tender in a dashboard DC receptacle as was discussed, the following things concern me:

i could pretty easily leave rig plugged in w/house solenoid in USE and use battery tender/minder in a 'cigarette lighter' DC port.

1) is constant trickling to 13+V better for batts?

2) does the GM 2005 chevy 6.0L have a live DC receptacle as standard (not RV builder) feature

3} what worries me most is could the DC receptacle cause some other dashboard lights/gauges/switches to blow a fuse?
burlmart
Explorer
Mar 22, 2016
a while back, after i found the chassis-house solenoid relay part of the Intellec Bidirectional Isolator Relay Delay device (BIRD) was sticking ON like its predecessor also did, i disabled the solenoid. it is the upper silvery solenoid in the pic. i took off its small DC power wires and pulled out the 5 amp fuse. both batts are now isolated. the left large gauge terminal goes to chassis batt and the right goes to house batt.

the BIRD device is just behind the house batt which is accessible thru an outside access door. i ran a short wire from the left solenoid chassis terminal to a screw into the wood floor over the house batt. both batts are side terminal 'starting batteries' and about 9 mos old. when parked at home, i put house battery disconnect solenoid (lower one in pic) in STORE, open the access door, and remove the positive cable from the house batt.

about every week, i open the access door and read 12.75V on the house batt, but about 12.58V for the chassis. i connect an external battery charger to the screw and ground terminal of house batt and charge chassis at 10 amps/hr for 3 hre, at which time it reads 13.07V. a week later, repeat process, sometimes giving the house batt a little charge, as well.

batts are happier than anytime before when on the BIRD.

is constant trickling to 13+V better for batts?

i could pretty easily leave rig plugged in w/house solenoid in USE and use battery tender/minder in a 'cigarette lighter' DC port.

but does the 2005 chevy 6.0L have a live DC receptacle?

and, could it cause some other thing to blow a fuse?
EMD360
Explorer
Mar 22, 2016
Never thought of trickle charging the chassis battery through the 12 volt port. What a convenient way to keep the chassis battery charged when the RV is plugged in. But what have I missed while not reading rv.net this winter?
IAMICHABOD
Explorer II
Mar 08, 2016
Bordercollie wrote:
Product name is "Battery Minder". This product is supposed to be able to de-sulphate tired batteries with pulse technology:

http://www.amazon.com/BatteryMINDer-Model-1510-Maintenance-Desulfator/dp/B00Q3CM2QY/ref=sr_1_1?ie=UTF8&qid=1457454363&sr=8-1&keywords=batteryminder
Bordercollie
Explorer
Mar 08, 2016
Product name is "Battery Minder". This product is supposed to be able to de-sulphate tired batteries with pulse technology:

http://www.amazon.com/BatteryMINDer-Model-1510-Maintenance-Desulfator/dp/B00Q3CM2QY/ref=sr_1_1?ie=UTF8&qid=1457454363&sr=8-1&keywords=batteryminder
pnichols
Explorer II
Mar 06, 2016
klutchdust wrote:
Thanks for those pics. I have Black and Decker battery minders and I just ventured out into the rain, yes beautiful rain, and saw that the alligator clips can be unplugged. Into my garage and I found the adapter for the accessory port. At the time of purchase I must have wondered what the heck and put them in the power cord drawer. Wife even wondered why the big smile on my face, I told her once again the forum made things easier...

Paul ... glad to be of some help. It sounds like you still had your BatteryMINDer's 12V receptacle plug - what luck.

I've used this trick for years on our Class C. The last Ford chassis battery lasted at least 6 years by taking care of it via our BatteryMINDer feeding a dash receptacle. Even when I replaced the Ford battery recently, I just did it "just in case" because it seemed to still be fine. I trust the Ford OEM battery quality, but the model I use in our E450 Class C is not what came in it. Shortly after buying our RV, I upgraded to the Ford OEM battery recommended for their diesel engines so as to have chassis battery over-kill.

P.S. I'm not so sure about the "beautiful rain" though. We have a large oak tree growing up out of a circular opening on our front deck. A couple of it's large limbs broke off during the rain storm last night and they landed right on our home's roof. Luckily, they didn't seem - as far as I can tell yet - to have penetrated the roof enough to make it leak, but it'll be a major tree job to have it cleaned up. We'll have another of it's big limbs that hangs over our Class C removed at the same time!
wearenh
Explorer
Mar 06, 2016
klutchdust wrote:
pnichols wrote:
...chassis battery charged by plugging a BatteryMINDer into a regular 120V RV receptacle and then plugging it's output cord into a regular 12V dash receptacle in the cab. The Ford's cab 12V receptacles are always hot...

Can you tell me the brand of battery minder that you are referring to. Mine all have alligator clips. What a great idea.

We do the exact same thing!

Battery Tender Cig Lighter adapter $6.50 incl shipping

Battery Tender Jr $25 incl shipping

.
Jim_Shoe
Explorer
Mar 06, 2016
I use an engine battery blade disconnect switch. Ace Hardware sells them. Probably most any hardware store as well.
Like this.
klutchdust
Explorer II
Mar 06, 2016
pnichols wrote:
klutchdust wrote:
Can you tell me the brand of battery minder that you are referring to. Mine all have alligator clips. What a great idea.

I use this little BatteryMINDer Plus to maintain our Class C motorhome's chassis battery 24/7 whenever the motorhome is in "storage" (in our backyard and always plugged into a 120V 20amp outlet on the side of our house):

http://www.northerntool.com/shop/tools/product_200332201_200332201

With the BatteryMINDer Plus I also bought this little optional adapter for it's output cable so that you can plug it's output into our Ford cab's regular always-hot 12V receptacle to "backfeed" into the Ford 12V system while the ignition switch is OFF:

http://www.northerntool.com/shop/tools/product_200365185_200365185

You can sometimes get the older model BatteryMINDer Plus that I show at great sale prices. I use another identical one in the shop to maintain other small garden tool batteries.

Thanks for those pics. I have Black and Decker battery minders and I just ventured out into the rain, yes beautiful rain, and saw that the alligator clips can be unplugged. Into my garage and I found the adapter for the accessory port. At the time of purchase I must have wondered what the heck and put them in the power cord drawer. Wife even wondered why the big smile on my face, I told her once again the forum made things easier...

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