Chassis Battery Charging

[DMajors]

Last week I had my (new to me) 2006 Discovery in the driveway plugged in to a 120VAC outlet. I did not disconnect main or aux. I have made the assumption that main is the chassis batteries and aux is the house batteries. In any event when I went to start up last Friday it would not turn over. I connected a battery charger for an hour after which it started with no difficulty. I drove it for 220 miles to a campground disabled main, measured the voltage on the battery Saturday morning and it was 12.71V. Kept main disabled and started Sunday with no problem. Is it necessary to disable main when plugged in. Do the chassis batteries charge when on shore power or only when engine is running? I was certainly in and out a lot and the steps got a workout before I figured out how to leave them out. Played the dash radio as well and for some reason the outside radio kept turning on as well. One thing I did not mention was I tried holding down the aux start switch which did not work, would not turn over. A different problem i guess. Any input appreciated still learning

[Skip426]

A belated , Welcome to iRV2.

Many coaches come from the factory without the ability to charge, the chassis batteries on shore power, and some are wired that the boost switch gets it's power from the chassis battery so if that battery is dead there will be no connection.
Many owners install their own maintenance charger, for the chassis battery.

[Skip426]

Many are using one of these.

[Old Bounder]

Your Discovery is designed to charge the chassis batteries from the converter/charger while plugged into shore power. It sounds like your isolator solenoid may be defective. That solenoid is used to make the connection between chassis and house batteries for charging and also for the aux start function. On your Discovery, it is located externally to the BCC (Battery Control Center).

[normandlegra]

DMajors, usually the chassis (engine) batteries do not get charged when pluged into shore power; not to drain them, just flip your chassis battery cut off switch to OFF and you will be able to start it any time after.
p.s. I keep a portable 5 WATT solar panel connected to my chassis batteries while in storage.

[Old Bounder]

Originally Posted by normandlegra

..... usually the chassis (engine) batteries do not get charged when pluged into shore power; not to drain them, just flip your chassis battery cut off switch to OFF and you will be able to start it any time after.

This is erroneous information. Fleetwood coaches, such as the OP's, have had the ability to charge the chassis batteries from shore power for more than twenty years.

I would say that is is UN-usual for a modern coach NOT to have that capability.

[normandlegra]

Originally Posted by Old Bounder

This is erroneous information. Fleetwood coaches, such as the OP's, have had the ability to charge the chassis batteries from shore power for more than twenty years.

I would say that is is UN-usual for a modern coach NOT to have that capability.

You speak for yourself and your Fleetwood product, but on my newer Gulfstream, the chassis battery does not get charged from shore power.

[Old Bounder]

Originally Posted by normandlegra

You speak for yourself and your Fleetwood product, but on my newer Gulfstream, the chassis battery does not get charged from shore power.

You are correct, I can't speak to why Gulfstream would not spend the bucks to install such a useful battery control feature.

Like I stated, ALL Fleetwood coaches (and many others, like Newmar, Damon and HR) have provided this capability for over 20 years. It is normal, these days on quality coaches.

[DMajors]

I have located the isolator solenoid. Should it be energised when on shore power. Should it charge when on genset?

Dana

[Old Bounder]

Originally Posted by DMajors

I have located the isolator solenoid. Should it be energised when on shore power. Should it charge when on genset?

Dana

The answers are YES and YES.

Here is a document that explains the function and operation of that solenoid as well as the entire BCC.

Any questions, just ask.

[bhale]

Should the coach batteries charge when the engine is running or does just the chassis battrry charge?

[hkunz]

Originally Posted by Old Bounder

This is erroneous information. Fleetwood coaches, such as the OP's, have had the ability to charge the chassis batteries from shore power for more than twenty years.

I would say that is is UN-usual for a modern coach NOT to have that capability.

Mine has never charged the chassis battery, and I've had my coach for 13 years and 67,000 miles. I never missed it because i never knew I was supposed to have it; I just use a trickle charger.

Where would this thing be on a 2002 Revolution, so i can check it?


And, now that I think about it, the coach batteries don't charge while the engine is running, either. Could these two issues be linked?

[Skip426]

Originally Posted by bhale

Should the coach batteries charge when the engine is running or does just the chassis battrry charge?

All batteries should charge from the alternator, with the engine running.

How the alternator power is distributed to both sets of batteries , varies from coach to coach.

[Old Bounder]

Originally Posted by hkunz

Mine has never charged the chassis battery, and I've had my coach for 13 years and 67,000 miles. I never missed it because i never knew I was supposed to have it; I just use a trickle charger.

Where would this thing be on a 2002 Revolution, so i can check it?


And, now that I think about it, the coach batteries don't charge while the engine is running, either. Could these two issues be linked?

Try your Aux Start switch to see if it works. Either jam a toothpick along side the switch button or have an assistant hold it down while testing. The isolator relay should close and connect the batteries together. Charging from engine alternator to house or from inverter charger to chassis should occur.

Judging from your symptoms, I would suspect the isolator solenoid is bad. The solenoid will have large battery sized cables from each bank attached to it.