Battery dying

[Jonnypip]

I have a 2016 winebago travel trailer ,my battery dies even with the main battery switch turned off.its a new deep cycle battery any ideas let me know

[60sumtin]

How long does it take to die? How well was it maintained? They will self discharge over time and if not fully charged while on the charger will sulphate shortening subsequent charged time.

[curmudgeon59]

spend $5 for a battery acid tester at an auto parts store (little bulb with a glass tube). You suck up some of the acid from each cell in the battery and see how it reads. You might very well have a failed cell; it can happen even to a newer battery. If you need a replacement, look to the "marine/deep cycle" type, which may be a bit more solidly constructed.

[keymastr]

With the battery charged you need to use a multi-tester to see whether there is a current draw when the battery switch is in the off position. The draw from smoke/propane detectors can kill a battery in a few days. In a motorhome they are usually hooked up direct and do not shut down with the battery switch but in a trailer they should be off when the switch is off. The only thing wired direct on my trailer is the 10 watt solar panel and the tongue jack.

[Chiefblueman]

Your main battery switch may not disconnect all loads from the battery. Things like your propane alarm may still be connected.
An easy way to check this is to turn the switch to "off", remove the negative cable from the battery, then connect a simple test light between the negative cable and the post on the battery. If there is any load on the battery, the test light will light up. If no load, no light.

I rewired my factory disconnect to remove all loads. You could also install a disconnect at the battery. Before I did this my battery would be dead in less than a week. If your battery has been deeply discharged several times you may need a new battery.

A fully charged battery should remain sufficiently charged with loads disconnected for months.

[tuffr2]

You probably have a group 24 battery. Invest in a new bigger battery box and buy a group 29 or 31 battery. They are a lot better than group 24 batteries.

[billyw]

I used to worry about stuff like that, then I installed 150 watts of solar power. My batteries are topped off and ready for action at all times, despite the various parasitic loads.