Roadrunner2 Report post Posted October 2, 2019 Neighbor who is unfamiliar with RVs has a 2017 Thor Tuscany. Failed to plug back in after a trip. Sat unplugged for 3 weeks. Discovered and all batteries are 2 volts or less including the start batteries. We plugged in but they are not charging. I can't locate any tripped breakers and see the power is getting to the line monitor. Assume the batts may be bad now but shouldn't they take some kind of charge? I thought the inverter would drop out and protect the batteries if they dropped to 11 volts. Why did the start batts go down as the key was not left on. As you can see I am only a little better informed than neighbor. I guess I am seeking help on where to start isolating the problem. Thanks for help. Share this post Link to post Share on other sites
wolfe10 Report post Posted October 2, 2019 Most smart chargers/smart inverter-chargers will NOT try to charge a severely discharged battery, This is a safety issue. You will need to use a "stupid" charger to begin the process. Once they are charged past extremely deeply discharged, the smart charger should take over. Share this post Link to post Share on other sites
Roadrunner2 Report post Posted October 2, 2019 Thanks Wolfe10. Any guess on why the start batts went dead or why the inverter let the house kept discharging all the way down? Is there an option I need to set on the Magnum? Share this post Link to post Share on other sites
desertdeals69 Report post Posted October 2, 2019 There are several reasons that batteries go dead. A current draw or moisture on the top of the batteries or bad battery. Batteries should be kept clean and dry. Share this post Link to post Share on other sites
