Forum Discussion

cekkk's avatar
cekkk
Explorer
Jul 10, 2015

No Power

My 4 year old battery has been sitting, not charging, for nearly 5 months. I have a new battery purchased to replace it, hoping to do that before what is happening happened. Dumb. So now I plug the power cord into my truck and nada.

It's run down, but, one, shouldn't it be grabbing from the truck? The battery disconnect switch is open.

I think it would take a charge if I plug the TT power cord into shore power. Would you try that?

My aim is to get the TT up to my garage where it will be easier to switch out the batteries and do other maintenance. Also to learn something here. Thanks.

7 Replies

  • Vulcan_Rider's avatar
    Vulcan_Rider
    Explorer
    Jul 11, 2015
    cekkk wrote:

    I checked the voltage on the new battery a couple days ago, it's fine. Thanks to all.


    "fine" can mean a lot of different things and doesn't necessarily mean fully charged......and that is important for a new battery.

    If it's an AGM battery, you might need to see a resting voltage of 12.9 to indicate a full charge.
  • cekkk's avatar
    cekkk
    Explorer
    Jul 10, 2015
    I used the wrong word on the disconnect switch. It was closed. I guess open breaks the circuit. Anyway, after a couple hours the light on the tongue jack works. We're in monsoon season and I'll have to wait to move the TT in the morning.

    I checked the voltage on the new battery a couple days ago, it's fine. Thanks to all.
  • 2oldman's avatar
    2oldman
    Explorer II
    Jul 10, 2015
    It's very wise to have a voltmeter handy when doing this kind of work.
  • cekkk's avatar
    cekkk
    Explorer
    Jul 10, 2015
    Thanks, OB, I guess you just taught me that plugging in to TV still requires using the TT's battery. I'll plug it into shore power a while and see if it takes enough charge by sunset to raise the tongue jack. Otherwise, I'll catch it in the morning, using new or old battery.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Jul 10, 2015
    And even when connected to truck..truck will NOT charge a very low/dead trailer battery. Truck charge line is really for maintaining charge on battery while in transit.

    Now you could use jumper cables from truck battery to trailer battery but that will also require time.
  • Vulcan_Rider's avatar
    Vulcan_Rider
    Explorer
    Jul 10, 2015
    ScottG wrote:
    If the battery disconnect switch is open, maybe even the truck isn't really connected to the battery.


    Not maybe, for sure.

    The battery disconnect switch disconnects the TT battery......from everything.

    If you have not CLOSED the battery switch, you don't really know yet if the trailer battery is dead or not.

    In any case, the trailer battery will NOT draw from the truck except when the engine is running. That's a safety to prevent you from drawing down everything and being stranded.

    Why do you need power to the TT to move it ?

    Please be sure that your new battery is fully charged BEFORE installing it.
  • ScottG's avatar
    ScottG
    Nomad
    Jul 10, 2015
    If the battery disconnect switch is open, maybe even the truck isn't really connected to the battery.

About Technical Issues

Having RV issues? Connect with others who have been in your shoes.24,370 PostsLatest Activity: Mar 17, 2026