Community Forums

preach2u · 07-17-2021, 08:11 AM

I have been dealing with a charging issue on this 2004 dolphin. The batteries are new, good, charged. The interconnect solenoid has been replaced. The charger/converter is working.
When plugged into shore power the batteries eventually begin to lose their charge and never recharge without starting the coach engine or using a battery charger- at which time they will again discharge after a few days of being connected (even when connected to shore power.)
I've been in touch with rv custom products and am considering replacing the battery control center, but am wondering if anyone has any more suggestions. It just won't charge on shore power... any ideas?

MrMark52 · 07-17-2021, 08:54 AM

Are you sure the converter is working?

What tests have you done on it?

Whose converter (manufacturer)? If it’s an old MagnaTek or linear design converter - time for a new one, working or not. The old linear ones will cook your batteries.
See “Progressive Dynamics” for a drop-in replacement.

twinboat · 07-17-2021, 09:16 AM

If your engine charges the house batteries, the interconnect solenoid and battery control center are working.

If your batteries are not charging while on shore power the converter/charger is not working. It sends the charge right to the batteries and does not enter the BBC or interconnect.
The interconnect connects the house and chassis batteries together. Each battery bank has its own charging system.

If the converter/charger is working 13+ volts output, its not getting to the batteries.

Is the battery disconnect switch on ?

BOOZE TRAVEL · 07-17-2021, 11:31 AM

When my converter/charger was dying it was tough to figure out. It would charge and not charge on and off. I kept checking it and it was putting out power every time I put a meter to it, then 1 time it only showed a couple of volts so I left the meter on and figured out what it was doing. This took about a week while boondocking due to only running the generator in the mornings.
The next issue was that I replaced a 60a unit with a 100 Amp unit and it wouldn't get the charge to the batteries. I called the BCC manufacturer and they said the BCC was only good for 45amps and the original 60amp probably sent less than 45a. They had me wire the new charger/converter directly to the batteries and the problem was solved along with my batteries being charged much faster.

FLRosebud · 07-17-2021, 12:39 PM

I had this same issue in my 2006 SeaBreeze, and "twinboat" is spot on. That was my problem.

Al

preach2u · 07-17-2021, 02:21 PM

Thank you all, the charger/converter is new and working. The battery connect switch is on, and connected. I’m puzzled because it doesn’t appear that the “charge” is making it to the batteries when on shore power. So, what would prevent that from happening besides the disconnect switch? And I am electrically challenged.

preach2u · 07-17-2021, 02:34 PM

Twinboat,
the charger/converter is new and working. The battery connect switch is on, and connected. I’m puzzled because it doesn’t appear that the “charge” is making it to the batteries when on shore power. So, what would prevent that from happening besides the disconnect switch? And I am electrically challenged.

MrMark52 · 07-17-2021, 02:44 PM

What tells you the converter/charger is working? Just because some lights are on in the convertor doesn’t mean anything but the lights are on.

Using a voltmeter have you measured the convertor’s voltage output, both when unplugged and when plugged in?

If you have, then I would put one lead of the voltmeter on the positive output terminal of the convertor, and the other end on the positive terminal of one of the coach batteries. If you read charging voltage (positive or negative, doesn’t matter at this point), then something isn’t connected on the positive side.
If you read 0 volts, then move the meter leads to the negative convertor post and negative battery post of the coach batteries. Again, if you thread anything other than 0 volts (positive or negative, doesn’t matter) then you’ve got a broken ground somewhere between the convertor and the batteries.

The BCC works through the emergency start solenoid to connect the coach batteries to the chassis batteries. As “twin boat” has said, that is not your problem and is out of the picture.

Whose convertor are you using? It would help to know so a wiring diagram/schematic could be reviewed.

preach2u · 07-17-2021, 02:56 PM

MrMark52, I have checked the converter when plugged in and it is good voltage. I did not check when not plugged in, but will when I get back to rig. I will check the other suggestions you have and reply. I appreciate the help.

wolfe10 · 07-17-2021, 03:06 PM

Yes, please post the actual VOLTAGE from your DIGITAL VOLTMETER.

"Good voltage" is an opinion-- facts will give us/you more to work with.

If you don't have one, they are under $20 and almost mandatory if you own an RV.

MrMark52 · 07-17-2021, 03:26 PM

And tell us what your working with!

Whose convertor? Take a picture!

Take a picture of the battery “Use/Store” disconnect control panel.

Take a picture of the battery disconnect electrical panel - there will be 2 or 3 heavy solenoids in it. Usually located under the engine hood of the coach.

And while your there, check for fuses on the solenoids - if there are any, check them to be sure they are good.

You should also hear one of those solenoids “thump” when you hit the “Use/Store” switch.
With that, you should also read, and possibly see a voltage change, between the battery side of the coach battery disconnect solenoid and ground as it changes state from “Store” to “Use” and back.
It should read convertor output voltage when in “Use” mode, and that voltage should be greater than 12.8 volts.

chboone · 07-18-2021, 01:19 AM

Quote:

Originally Posted by MrMark52

there will be 2 or 3 heavy solenoids in it. Usually located under the engine hood of the coach.

On National RV's there will be 2 solenoids, 1 main latching house solenoid and 1 interconnect/start boost solenoid. The BCC and converter/charger is in the bay on passenger side between the entry door and front wheel.

twinboat · 07-18-2021, 04:15 AM

There should be a fuse/breaker within 2 feet of the batteries for the converter output. Follow your positive battery cable.

preach2u · 07-18-2021, 03:02 PM

Sorry for late response. Here are readings:

Gauge in the motorhome shows 12.4 for both house and chassis batteries.
Readings at batteries: chassis is 12.54; coach batteries are 6.28 and 6.27
Converter is power max pm3-55lk, new, and is producing 13.7 volts plugged in.
When one lead is placed on battery positive post and the charger positive post reading is 12.56; battery pod and charger negative is -2.07
One lead on negative post of battery and charger is 6.28 and when battery neg post and charger positive terminal it is -8.35.
I appreciate any suggestions. Thank you