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Dragonfly's avatar
Dragonfly
Explorer
Jun 28, 2015

Would a dead house battery disable 12V when on shore power

I am new to this forum having just found a heck of a deal on a Proven Tiger CX, on a 2011, 4WD, F350 regular cab. The good news is that it only has 7,500 miles on it. The bad news is that is probably sat too long after the original owner died and the family pondered what to do with it. One casualty includes the house batteries, both totally dry, one cracked and won't hold water. They are Interstate, open cell, and I believe they are 6 volt. I never had 6 volt but the batteries appear smaller and I hear that Proven uses them in their vehicles.

My question is this. 12 volt systems work with the truck engine running. 120 volt works when plugged in or with the generator running. However, 12 volt only works with the engine running and not when plugged in or with the generator on. Is this because of the obviously dead batteries? I will of course be replacing the batteries and hope the dead ones are blocking 12V power when on 120. If not, I guess the next possible culprit is the converter.

PS: I will search the forum but would also welcome thoughts on replacing the two 6 volt batteries. They are under the floor and NEAR IMPOSSIBLE to access. So I am thinking some sort of sealed, maintenance free battery. A friend with a Proven suggests AGM but I don't know whether they are worth the extra cost.
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  • Dragonfly's avatar
    Dragonfly
    Explorer
    Jun 28, 2015
    enblethen wrote:
    Your rig may have a battery disconnect which would not allow battery(ies) to work.
    The 120 volt system should be powering a converter which charges the battery system. Check to make sure converter is operating and breakers are on. Check for main battery and converter fuses in the 12 volt DC power distribution panel. These fuses are normally adjacent to the 120 volt circuit breakers behind small metal plate.
    Disconnect the bad battery and see if system operates. Look for make and model of the converter.

    ______________________
    I have tried 12V with the battery disconnect on and off. Earlier I also had no 120 volt when plugged in. Flipping breakers did nothing but I did solve it by turning off all circuit breakers while unplugged, then plugging in, then turning on each breaker one by one. Although that seems a bit odd, apparently the circuit breakers are now OK.

    Yes, I should have checked all those little fuses which I will do now. And good point, I should try disconnecting the dead batteries to see if that does anything. But with both dead and one cracked open, they are probably in effect disconnected already.

    THANKS
  • enblethen's avatar
    enblethen
    Nomad
    Jun 28, 2015
    Your rig may have a battery disconnect which would not allow battery(ies) to work.
    The 120 volt system should be powering a converter which charges the battery system. Check to make sure converter is operating and breakers are on. Check for main battery and converter fuses in the 12 volt DC power distribution panel. These fuses are normally adjacent to the 120 volt circuit breakers behind small metal plate.
    Disconnect the bad battery and see if system operates. Look for make and model of the converter.

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