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elhajj33's avatar
elhajj33
Explorer
Dec 22, 2015

Solar charger but still dead batteries

A few weeks ago my coach's batteries (coach is a 2009 fleetwood excursion 40x DP) were dead when I went to pull it out of storage . Completely dead - even the aux start would not work. Couldn't even get the genie going until we put a charger on it.

I figured maybe i had left the inverter on (possible i guess...). Anyhow got it charged, running, and plugged in for a few days.

It sat in storage again for a week and this morning, it would not start again. It wasn't completely drained, but it still wouldn't start without running genie (luckily i was able to get that started).

I made sure I had nothing on at all before i put it into storage last week and I can't make sense of what's going on.

The batteries are new (or so says the dealership where i bought the coach from; will need to double check), coach does have a solar panel, and the batteries are not turned off.

Any thoughts on this. I'm not sure what could be causing the drain.
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  • dahkota's avatar
    dahkota
    Explorer
    Dec 22, 2015
    We bought a brand new coach from a dealer (with 'brand new' batteries). Within six months we realized the problems we had were directly attributable to the batteries - they had been misused so much on the lot that they wouldn't hold a decent charge for long.
  • RoyB's avatar
    RoyB
    Explorer II
    Dec 22, 2015
    Of course once the batteries get drained down to absolutely nothing like described here they are damaged and will never be the same after that... Most often they need replaced when this happens...

    Sometimes a complete disconnect by removing the ground terminal is the best approach instead of relying on disconnect switches. A fully charged battery will sit fully disconnected on the shelf or in the battery box for a long time and not drain down or freeze up.

    Using a multimeter across the battery terminal is a great way to determine if they are being charged. The normal fully charged DC VOLTAGE of 12.6-7VDC will show an increase of 13.2. or 13.6VDC when being charged. Certainly takes the guessing out of the procedure using a multimeter...

    We watch our batteries like a hawk when using them and when in storage as they are just too expensive for me to not do this...

    Roy Ken
  • Gjac's avatar
    Gjac
    Explorer III
    Dec 22, 2015
    Need a lot more info to help. Age and type of batteries? How many amps does your solar charger put out? How many amps does your built in charger and how long have you charged from shore power? Have you checked your parasitic amp draw with everything shut off? Do you have a battery shut off switch? How are you checking your batteries to know they are fully charged? From your post it sounds like your batteries are going dead in a week after charging is that correct? Have you checked the water level in the batteries? If you reply to the questions you will get better answers to your battery problems otherwise you will just get guesses.
  • redsb3's avatar
    redsb3
    Explorer
    Dec 22, 2015
    My guess would be the solar controller is not working and batteries are not being charged. If you do disconnect batteries, make sure you disable the solar first.
  • Dutch_12078's avatar
    Dutch_12078
    Explorer III
    Dec 22, 2015
    Try disconnecting the battery ground cable the next time it will sit for a week. If it starts ok when you reconnect the cable, the battery is good and there's a draw somewhere else that's pulling it down. The quick fix in that case would be a battery disconnect switch that installs on the battery terminal, but finding the draw would be the better answer. That can be a long process though, unless you have a good multi-meter on hand and know how to use it for load testing.

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