Chassis battery won’t charge from converter

[Capone]

I have a 2000 Coachman Catalina 330 mbs and the Chasis battery is not being charged by the converter all of a sudden. I have had this coach for3 years and it has always kept all of the batteries charged when plugged in to shore power, but toward the end of last season I noticed that the chasis battery was not being maintained. The battery will charge from the altinator but will slowly drain down during periods of more than 3 weeks or so without running the coach, and the coach batteries are still being maintained by the converter. Owners manual says that use/store switch must be in use for chasis battery to charge from converter and when I press the switch to use I hear what sounds like a solenoid click but when I release the switch it click again which seems unusual to me. Any ideas are greatly appreciated and thanks in advance for your input.

[BigRabbitMan]

I put a heavy duty manual disconnect switch on my chassis batteries. When I park the coach, I disconnect the chassis batteries. They are always ready to go when I am ready and that can be several months later.

[jerseyjim]

As mentioned before, my chassis (engine start) battery is charged by the alternator. Only. So, you gotta run the engine to keep the charge up. However, when the engine is running, that ALSO charges the coach batteries.

I have a Trik-l-Charge and it works great. UNTIL....it discharges the coach batteries to make them not work.(Yeah, I know...there is supposed to be a "fail-safe here, but......)

I found the best way to use the Trik-l-Charge is when snowbirding...and the coach does not move for months.
Then, you are on shore power....that does charge the coach batteries, then the Trik-L-Charger can work and keep the 12V chassis battery charged.

[wildmanbaker]

I believe that Fleetwood MHs from 95 on should charge the chassis battery when on shore power, or running the generator. Other manufactures have caught up, but it was slow. If you contact the manufacture, they may be able to sent you the 12 volt prints, or point you to where they may be online. It will just take time troubleshooting to find the problem.

[Sam_Spade]

Capone wrote:
so adding a trickle charger is my plan for resolution.

A "trickle charger" is NOT the solution for long term storage. They tend to float at too high a voltage and can be worse than nothing.

You need small AUTOMATIC tender type battery maintainer.

[Joe_and_Lori]

I am finding similar issues. My 99 Rex haul ford chassis would not seem to charge chassis battery but then it seemed to start. Were full timing now and I notice more than before. But just the other day the chassis battery went dead while plugged in. I charged it up and now I notice what I think is the battery parallel solenoid cycling on and off. It does not do it all the time. Is that how it charges the chassis battery by activating the battery solenoid?

[wvabeer]

According to my 99 Newmar manual it says.
The coach and chassis batteries are recharged by the vehicle's electrical system whenever the engine is running. A decline in the coach battery voltage may be noticed while the chassis batteries are being charged. The converter will automatically charge the coach batteries when the unit is connected to a 120 volt outside source. The chassis batteries are isolated from the coach batteries. This prevents the chassis batteries from being drained by the interior 12 volt equipment, allowing ample voltage for the engine ignition.

[Capone]

Even though my owners manual specifically states the chasis battery will only be charged when the disconnect switch is in the use position, and for the first two years we owned the coach the battery had no problem staying charged even after two months of not being used, I am starting to believe that the coach battery is not charged by the converter so adding a trickle charger is my plan for resolution.

[mowermech]

In my lifetime I have owned three Class A motorhomes (1977, 1988, and 2002) and one Class C (1995).
None of them charged the chassis battery from the converter. The chassis battery was charged by the engine alternator ONLY.
The engines were a 440 Dodge, a 454 GM, a Ford V10, and in the Class C a Ford 460.

[D_E_Bishop]

CA Traveler wrote:
11.8V is a severely discharged battery. At 2 hours of charging it should be in the 13V+ range headed towards a bulk charge of 14.8V.

When you resolve the charging load test the batteries.

Load test is my suggestion too. I had a mode switch(Battery Boost) solenoid. Showed 223.0 ohms when closed. High resistance for a switch and it wasn't testing good with the load test meter, new solenoid and battery, works great.

[wvabeer]

I am having this problem too.

[Sam_Spade]

Capone wrote:
so the plan is to leave it as is until morning and recheck the voltage.

And that will prove......exactly nothing......without knowing what is supposed to happen in that situation.

Are you plugged into shore power during this "test" ??

[CA_Traveler]

11.8V is a severely discharged battery. At 2 hours of charging it should be in the 13V+ range headed towards a bulk charge of 14.8V.

When you resolve the charging load test the batteries.

[Capone]

Ok, so a little closer. As it turns out there are two solenoids in a box under the hood just below the a/c coil and I was able to determine that only one small wire connected to the coil of one of the solenoids has voltage on it with the use/store switch set to use, but if the switch is set to store there is voltage on just about every wire in the box. After leaving the switch in store for about 2 hours my voltage went from 11.82 to 11.83 so the plan is to leave it as is until morning and recheck the voltage.

[Capone]

Thanks guys, at this point I have checked for blown fuses, and with the help of a friend to push the button I believe I have determined the solenoid location to be under the dash in the area of the ac cool. As I said I know the converter is supposed to charge all of the batteries as it had no trouble doing so prior to late last season, so the coach sat unused from Nov. - Mar but still started on our first trip of last year without having to use the emerg. start switch. Now that I know what general area the solenoid is in I will do a little further diagnoses. Just so you are aware I am very well versed with the use of tools such as multi-meters as I am a master HVAC Tech. and an Extra class Amature radio operator. Thanks again for the ideas they are very good solutions if I can’t beat the gremlins.
Enjoy the journey. Tony/ KU4VA