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Bigdummy86's avatar
Bigdummy86
Explorer
Oct 15, 2015

12v problems with 2005 allegro

Hello -
I'm new to the forums and because of my remote location I'm looking for some assistance.

Last time I took out my 2005 tiffin allegro class a out the generator had failed to charge my batteries, and I ended up using the chassis to do the charging. I have since replaced the inverter which I tested bad with a voltmeter. Now that I have the new inverter in, and even if I remove the inverter I have no 12v power for anything. I've done some basic testing near the inverter and everything seems to read okay. Both batteries are charged to 13+volts (chassis and house batteries). I've got a few hours into this already.

I have tested fuses and everything looks good. Any suggestions where to look next? Curious thing is that I have a solenoid that reads lesser 11.5 V when I test it across the main ground. I would think even 11.5 volts would be enough to power my 12v system.

I also hear a "clicking" noise when I press the 12v switch to try and turn it on, very similar to when a car battery fails to start a car. This is coming from a solenoid that reads the full 13v.

Any other suggestions to what to test or what may be wrong? I've tried jumping across the solenoid that reads 11.5v and still had no success.
Class A

9 Replies

  • Tinstar's avatar
    Tinstar
    Explorer
    Oct 16, 2015
    Do you have a switch near your door that disconnects all 12 volt systems. Mine is just an on/off toggle switch and most all motorhomes have them.
  • Bigdummy86's avatar
    Bigdummy86
    Explorer
    Oct 15, 2015
    I am getting power to both sides of the solenoid regardless of whether the switch is on or off. It drops when I start the generator and still no 12v power with the generator running. I also did try jumping from the post that feeds the solenoid to a post after the solenoid which still wouldn't give me 12v power. I've checked all of the smaller fuses on the panel and they all look good. Haven't checked the bigger fuses covered with a jacket. Now I'm thinking it may be a fuse after the solenoids that feed out to the system?
  • DrewE's avatar
    DrewE
    Explorer II
    Oct 15, 2015
    Logically, the problem would seem to be between the battery and the 12V distribution panel. There should be a fuse or circuit breaker near the battery (which may be popped/blown), and apparently a disconnect solenoid switch since you mention that, and possibly one or more main/input fuses at the fuse panel.

    If you have 12V at the battery side large terminal of the disconnect solenoid and no power at the other side, and it won't switch on, that's your problem. You could bypass it by connecting both leads to one or the other of the large terminals (with the 12V power disconnected at the battery, of course) to get power to the RV, but of course that means you won't be able to disconnect it with the switch for storage.
  • Bigdummy86's avatar
    Bigdummy86
    Explorer
    Oct 15, 2015
    Yeah inverter that plugs into a working outlet. Charging is fine on batteries. Just have no 12v power at all, no outside lights, inside lights, nothing on 12v system works. Batteries are all charged up and reading fine with volt meter.
  • sch911's avatar
    sch911
    Explorer
    Oct 15, 2015
    donn0128 wrote:
    INverterr CONverter? There is a difference. Unless you installed a INverter/charger you will not get any battery charging.


    Pretty sure he means inverter/charger since most DP's have those.
    Is the inverter/charger getting 120V? What does the control panel say?
  • donn0128's avatar
    donn0128
    Explorer II
    Oct 15, 2015
    INverterr CONverter? There is a difference. Unless you installed a INverter/charger you will not get any battery charging.

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