Forum Discussion

jeremywatco's avatar
jeremywatco
Explorer
Jul 23, 2014

Alternator not charging house batteries

Hi Everyone,

I noticed after my last long road trip after departing with 100% charged batteries I arrived at my destination with about 10 amp hours discharged. I thought this was odd so I did a test and watched my battery display to confirm. When the coach is running the house batteries are not charging.

If I push and hold the AUX Start switch on the dash it will start charging them but as soon as I let go it stops.

Any thoughts?

2014 Fleetwood Storm.
Class A
  • LVJ58's avatar
    LVJ58
    Explorer
    Jul 23, 2014
    Possible isolator solenoid malfunctioning or faulty circuit board in your battery control center.

    When charging voltage from either alternator or converter reaches 13.5+ volts, isolator solenoid should engage charging both house & chassis batteries.

    Good luck with resolving your problem and do let us know the fix...
  • jeremywatco's avatar
    jeremywatco
    Explorer
    Jul 23, 2014
    Sounds like further testing is needed. THanks for the input.

    I'll run the batteries down to 60% or so and make sure the chassis batteries are charged and then keep a higher RPM and see what happens...

    Or I'll go buy some solar panels and forget about it!
  • fischer's avatar
    fischer
    Explorer
    Jul 23, 2014
    I think the house battery's won't charge at idle. You need a high idle for 20 seconds. also your battery needs to drop to a certain voltage before charging will happen. I dont know what the voltage is.
  • fischer's avatar
    fischer
    Explorer
    Jul 23, 2014
    Go inside your BCC(battery control center). Under the hood the cover comes right off. Check f1 thru f12 all should be 12v Inside the box is your charging relay ,main disconnect relay ,aux disconnect relay . If you google battery control center troubleshooting you will get diagram and troubleshooting guide. inside there is 2 or 3 resettable circuit breakers (small). ps f6 thru f12 need the ignition sw on
  • bluegypsy's avatar
    bluegypsy
    Explorer
    Jul 23, 2014
    On my rig (Fleetwood Discovery) the alternator charges the chassis batteries first, then switches to the house batteries (what I mean to say is there's some switchology somewhere that makes the juice go to one, then the other). I would guess that either the switchology is defective somehow, or your chassis battery is going bad, and taking all the charging "priority".
    If the switchology is bad, you may find your chassis battery is overcharged.

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