Community Forums

blkcloud · 01-21-2016, 04:28 PM

I got in my mh today and the cranking batteries were dead as a hammer.. It stays plugged up all the time and I have never had this issue before.. I jumped it off and put my meter on it.. With the big engine running my batteries showed 14.15 v my house batteries 6.62. With it plugged into shore power the batteries showed 12.65 house batt. 6.96. When I checked them with out the motor running and not plugged in the batteries showed 12.65 and house batt. 6.74.
My question.. Should the batteries show more volts when I have it on shore power? Thanks

Ranger Smith · 01-21-2016, 04:46 PM

Did your breaker on your inverter/charger trip? Also 6.96 is NOT good. Should be 12.5 at least. Usually chassis batteries won't charge when plugged in on the older Rv's

FreedomDream · 01-21-2016, 05:33 PM

Ditto. 6.7 volts is essentially a dead battery. Plug in a stand alone battery charger and charge the house batteries for several hours, wait about a half hour and take a reading. If not up around 12.7, you need new batteries.

dan-nickie · 01-21-2016, 06:13 PM

Is in your house batteries are six volt Batteries?

twinboat · 01-21-2016, 06:17 PM

Quote:

Originally Posted by dan-nickie

Is in your house batteries are six volt Batteries?

Good pickup,

I'll bet he is measuring a 6 volt battery with his meter.

To the OP, look at your batteries and measure the + and - of two of the batteries that have a jumper wire between them.

twinboat · 01-21-2016, 06:26 PM

Quote:

Originally Posted by blkcloud

I got in my mh today and the cranking batteries were dead as a hammer.. It stays plugged up all the time and I have never had this issue before.. I jumped it off and put my meter on it.. With the big engine running my batteries showed 14.15 v my house batteries 6.62. With it plugged into shore power the batteries showed 12.65 house batt. 6.96. When I checked them with out the motor running and not plugged in the batteries showed 12.65 and house batt. 6.74.
My question.. Should the batteries show more volts when I have it on shore power? Thanks

Once you started the engine, you put in a surface charge so measuring them was not accurate.

Even plugged in, it is likely that the start batteries are not charged from the charger unless you have an added small charger to do that.

If you are measuring each of the 6 volt batteries, your numbers make sense.

blkcloud · 01-22-2016, 12:56 PM

Yes they are 6 volt house batteries . Where would the on board charger be located? I'm sure it has to have one for the house batteries doesn't it..?? Or does the big motor charge those batteries also?

twinboat · 01-22-2016, 01:12 PM

Yes, there is definitely a charger for the house batteries. It may be an inverter / charger or a stand alone charger, other with your model will chime in.

Aside from that, almost all MHs will charge all of the batteries while the engine is running.

The shore cord or the generator will charge the house batteries, but back in 2000, it may not charge the start battery.

The fix is a trik-l-start or other small battery maintainer wired or plugged into the system.

Have you used the boost switch to start the big motor or actually jump start it ?

The boost switch connects the batteries together for jumping one or the other banks.

nothermark · 01-22-2016, 01:12 PM

Unless you have an whole house inverter your house batteries are probably charged by the converter located behind your DC fuse panel.

You should have two sources of DC. Then big engine alternator and the Inverter or Converter part of the Inverter that runs off the AC main. The alternator will charge the engine batteries while the converter charges the house batteries. There is usually some kind of additional control to feed Alternator power to the house batteries and less often some way to feed house power to the engine batteries when parked.

blkcloud · 01-22-2016, 02:25 PM

Yes they are 6 volt house batteries . Where would the on board charger be located? I'm sure it has to have one for the house batteries doesn't it..?? Or does the big motor charge those batteries also?

FreedomDream · 01-23-2016, 10:53 AM

Quote:

Originally Posted by blkcloud

Yes they are 6 volt house batteries . Where would the on board charger be located? I'm sure it has to have one for the house batteries doesn't it..?? Or does the big motor charge those batteries also?

Your "big" motor charges both the chassis battery(s) and the house (coach) batteries - if it is working properly. Shore power only charges the house (coach) batteries (if the charger is working properly) - unless you have an option like trik-l-start or amp-l-start which takes shore power and charges the chassis battery(s).

There is a device (usually near the chassis batteries) called the charging solenoid that takes the "big" engine's alternator power and charges the coach batteries. If that solenoid is defective, the engine will not put a charge in the house batteries. Your shore power, "on board" charger can be located anywhere near where the shore power enters the coach or it may not. My inverter/charger/converter is located mid ships in the ceiling of the basement. You can locate it by the ready light it emits when it is turned on.

Dr4Film · 01-23-2016, 11:05 AM

First things first!

Some models of Monaco coaches came with Bidirectional charging whereas other models did not. You have to determine whether your coach has the ability to keep ALL batteries fully charged while on engine power or shore/generator power.

If it does than next you need to find out what component is not working correctly and fix it.

If it did not then there are devices available to purchase that will keep ALL batteries fully charged no matter where the power is coming from.

Dr4Film ----- Richard