Hey folks I have a question about the 12 volt system on my 96 Damon Intruder.I have shore power and Generator Power and everthing works ok, however when I Unplug and not run the Generator my 12V system does nothing.I will say that my batteries do need replaced but I set up my Charger and put a good charge on the batteries and still no 12v system working at all. A few years ago I put an Xantrex converter in place of the old 6300 magnetek and absolutely loved it. Not once did my batteries overcharge and boil them out!!!Question is When I plug into shore power I used to be able to hear the converter fan kick in when the batteries needed a bit of charge and now I can not get it to kick on at all. Where do I start?? I have tested all the fuses inside the Mh and all the breakers and they seem to be working fine.I put a volt meter on what I believe is the wires coming back from the batteries and get a wierd 30v??On the control board itself should I be able to find a 120v power to the board and then a 12 to 14 volt going to the battery section??Hope this makes since.I did check the little disconect switch in the battery compartment and it seems to be fine.thanks for any input, as I'm now at a loss!!Dad

As an after thought I have two wires on the control board that is labled Bat Pos and the Other as Bat Neg. I put my meter on these and it shows 30V. ?? Why this is as I have 2 12 volt system for house batteries.Dad

Agree, 30 VDC makes no sense. Even if the 12 VDC batteries are wired in series instead of parallel like they should be, that would suggest that each battery is at 15 VDC???12 VDC batteries at rest will not exceed 13 VDC each. And, no 12 VDC charger would be able to charge to 30 VDC unless badly malfunctioning.

Are you plugged in or is the generator running when you read 30v? Do you have solar?

dad4papa2 wrote:When I plug into shore power I used to be able to hear the converter fan kick in when the batteries needed a bit of charge and now I can not get it to kick on at all. On the control board itself should I be able to find a 120v power to the board and then a 12 to 14 volt going to the battery section??Hope this makes since.It makes no since. Sounds like the converter is not working. That's easy to check with a voltmeter. Make SURE the batteries are good by measuring their resting voltage with no charging on them for at least 10 minutes.I don't know what control board you're talking about.

Well i went back out and run my meter checks again.With Shore power plugged in the Pos bat and neg bat terminals on the control board show 13.61 Volts (thats the White and green one in the top section of the converter on the right side.) With the power off they show .30 volts. I must have had my meter set wrong. When I test them at the battery terminals on the Battery I get 12.39 v. I think I will check all grounds and go from there.Any suggestions is great!!!Dad

No 12v power to Motorhome? | Good Sam Community

wa8yxm
Explorer III
Jul 13, 2020
dad4papa2 wrote:
Well i went back out and run my meter checks again.
With Shore power plugged in the Pos bat and neg bat terminals on the control board show 13.61 Volts (thats the White and green one in the top section of the converter on the right side.)
With the power off they show .30 volts. I must have had my meter set wrong.
When I test them at the battery terminals on the Battery I get 12.39 v.
I think I will check all grounds and go from there.
Any suggestions is great!!!
Dad

Two options
Option low-cost ONLY applies if you are metering the WIRE ends and not the batteries themselves. VERY and I mean VERY dirty connecton between battery and cable. Easy to test. Touch he probes to the battery or batteries themselves.

Option 2 (The expensive option) Batteries toast. HIGH RESISTANCE failure.. Remove to store for testing if you current have a pair of 12 volt marine/deep cycle consider going to GC-2 Golf car in series (6+6=12) you treat the pair like a big 12 volt (4d) battery for all things save lugging (same weight as a 4D but you only lug half at a time) 220 amp horus (give or take 10) 50% usable

The 12 volts you have now.. If MARINE/deep cycle only about 25% usable.
dad4papa2
Explorer
Jul 13, 2020
Another update in case anyone else runs into my issue.
Once I got the 12 volt system back on, I again realized that the fan was still not coming on on my Converter Charger that has always come on to cool the system as it was charging. It would always run for a minute and then shut off once the batteries were back up to par.

Here's what I found out after more continuous testing of everything.
Once I unpluged from shore power the old batteries were testing full charge but two days later would be dead.
Everytime I checked them they would at first show full charge. Then on day 2 nothing. So here I think there is one of two things wrong here.
1. Something is drawing the batteries down that I haven't found yet or
2. I had bad batteries.
I bit the bullet and bought new batteries and as soon as I hooked them up I had lights and when I plugged it into shore power the fan on the charger started running again.

So it now is up and running and if you run into this just take your batteries to be tested. I guess even with a bad cell they will sometimes give you a false reading!!

Problem Solved!
Thanks for the input to all.
Dad
dad4papa2
Explorer
Jun 24, 2020
No problem. I think always check that switch to make sure it is working!!! It took me over 8 hours to find it!! Not fun!!

Dad-- Thanks Again
opnspaces
Navigator II
Jun 24, 2020
Thanks for coming back and letting us know the fix.
dad4papa2
Explorer
Jun 24, 2020
Got it. Your were correct. The disconnect switch on the dash was in the connect location (on) but wasn't making contact somehow. I tinkered with it and all at once the crazy thing started working. I may need to check into the switch and see if it can be replaced.

Thanks very much for all the help on here. I truly appreciate it.

Happy traveling to you all!!

Dad
1995brave
Nomad
Jun 24, 2020
Sounds like your battery cut off switch is off or you have a fuse or circuit breaker blown between the batteries and the converter (white wire).
dad4papa2
Explorer
Jun 24, 2020
I have it unplugged now nd will see what happens to them. I'll update once I give them some time.
thankls so much for your help.
Dad
2oldman
Explorer II
Jun 24, 2020
It makes more sense. 12.39 is an acceptable reading, but you're still confusing me as to whether that's plugged in or not.
dad4papa2
Explorer
Jun 24, 2020
Just above the converter is the breakers and what I call the control board.

When I turn off all power I get .30v on the white wire and green wire.

When plugged in I get 12.39v. (Everything work when pluged in as in all the 12v lights etc.

when I unplug it I get nothing inside to work.

Hope this makes more since.(yesterday I hooked up my battery charger to the batteries and they showed 12.73 volt instantly and held right there while charging.

Thanks Dad
dad4papa2
Explorer
Jun 24, 2020
Maybe this will help if it is allowed.

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