Forum Discussion

dennislanier's avatar
dennislanier
Explorer
Dec 11, 2018

No 12volt power

First a little background information. I have a 2004 Jayco Class C with E450 chassis. Have not been able to use it in several months, but I do like to run the generator every so often to keep it working. For quite a while, the coach battery has been very low, so in order to start the generator, I just crank the V10 up, let it run a couple minutes, switch on the battery disconnect switch, and the generator gets its cranking power from the engine. However, today I went to start the generator and nothing happens. When I tried to switch on the disconnect switch, none of the 12volt lights or anything works. So my question is, do you think it is another bad disconnect switch or what. I replaced one about 9 months ago but it had different symptoms at the time. Also, if the coach battery is COMPLETELY dead will that cause this problem. Anyway, any advice or suggestions are appreciated.
Class C
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Dec 11, 2018
    House battery dead...due to lack of sufficient charging
    Parasitic loads from LP Detector etc drain battery within a couple weeks or less (depends on battery status)

    Use voltmeter and measure house & chassis battery voltages
  • STBRetired's avatar
    STBRetired
    Explorer
    Dec 11, 2018
    Once you get the generator fired, make sure that the converter or inverter/charger is charging the coach battery.
  • tenbear's avatar
    tenbear
    Explorer
    Dec 11, 2018
    I don't see anything in your post about charging your battery. Running the generator for a few minutes won't do much to charge it, and starting the engine discharges the battery quickly. As Old-Biscuit said, you need to get a voltmeter and see what your battery is doing. Remember, it takes hours to charge the battery but no where near as long to discharge it.
  • BFL13's avatar
    BFL13
    Explorer II
    Dec 12, 2018
    The alternator charging of the house battery is no longer enough to raise the house battery voltage enough to start the generator. The house battery has gone down too far.

    You will need a new house battery for sure. To just start the generator, perhaps a set of jumper cables and a good battery from somewhere will do it. (Even from your engine battery if the cables are long enough.)

    You do need a way to keep the house battery and engine battery charged up. Shore power, solar, or something.
  • dennislanier's avatar
    dennislanier
    Explorer
    Dec 12, 2018
    Thanks for the information guys. I went back out there today and when I started the truck engine, it gave enough power to start the generator which I ran under load for a while. I then turned everything off and removed the house battery and have it charging now. I doubt it is going to hold a charge as it is now 6 years old but we will see what happens. For some reason yesterday the engine would not turn the generator over, but today it did. Anyway I will charge the battery overnight and check it again. By the way the battery showed 12.4 volts AFTER I ran the generator, but like I said, it probably won't hold.
  • BarabooBob's avatar
    BarabooBob
    Explorer III
    Dec 12, 2018
    How long did you charge the battery with the generator? It will take several hours to charge the battery, maybe more than a day. I would plug in the RV and let the converter fully charge the battery. My Progressive Dynamics converter will run the battery through a "recondition Mode" which is suppose to help bring a questionable battery back to life My PD9245 helped me keep the battery performing in my Escaper (built on Toyota C & C) for several years.
  • dennislanier's avatar
    dennislanier
    Explorer
    Dec 12, 2018
    The generator started off the engine battery and ran for about an hour. I then removed the battery and put it on slow charge. I will let it charge overnight and check it tomorrow. Don’t have much confidence that it will take the charge but nothing to lose by trying.
  • Matt_Colie's avatar
    Matt_Colie
    Explorer II
    Dec 13, 2018
    Dennis,

    You may well be right, I mean that the house battery is toast.

    Let's get something else straight here, the generator only charges the house bank by using the converter/charger the same as if you are on shore power. If that is an old or less capable unit, you might consider replacing it with a modern multi-stage unit. Find out what it is and come back here for suggestions.

    Also, you kept talking about the battery as small and singular. If it is a single 12V and you expect to do any dry camping at all, then maybe you should try to replace it with a pair of GC2s. Golf cart batteries are designed to take some abuse. I just replaced an 8yo pair.

    Is the coach somewhere that you can get to shore power? If not, you might look into a tiny solar panel to change the house bank while the coach is stored.

    Matt
  • dennislanier's avatar
    dennislanier
    Explorer
    Dec 13, 2018
    Matt_Colie wrote:
    Dennis,

    You may well be right, I mean that the house battery is toast.

    Let's get something else straight here, the generator only charges the house bank by using the converter/charger the same as if you are on shore power. If that is an old or less capable unit, you might consider replacing it with a modern multi-stage unit. Find out what it is and come back here for suggestions.

    Also, you kept talking about the battery as small and singular. If it is a single 12V and you expect to do any dry camping at all, then maybe you should try to replace it with a pair of GC2s. Golf cart batteries are designed to take some abuse. I just replaced an 8yo pair.

    Is the coach somewhere that you can get to shore power? If not, you might look into a tiny solar panel to change the house bank while the coach is stored.

    Matt


    Thanks Matt. I just took the battery off the charger and will let it sit awhile and check the voltage then to see where I am. My 2004 Jayco I am sure has the original converter installed. Right now I am not going to buy a new battery or converter until I am sure I will be able to use the MH again. No sense spending money on a new battery that will just sit in the yard like it does now. Hoping for better times next year. Family situation prevents us from taking any kind of trips right now. If not better by spring time I will probably just sell it. Thanks for the information.
  • Harvey51's avatar
    Harvey51
    Explorer
    Dec 13, 2018
    Voltage on the battery while charging from engine or generator can be revealing. It needs to be over 14 volts for effective charging.

    The battery voltage immediately after charging will still be the charging voltage. It takes hours before it goes down to be of some use estimating the state of charge. I disconnected the house and engine batteries on our class C in September and they are still more than 12.6 volts. Solar is the answer but get at least 100 watt panel.

    A battery monitor displaying the % of full charge accurately by means of counting amp hours in and out can be had for $30 on eBay.

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