Battery dead 2016 24K Melbourne

[traveler1]

Just bought 2016 Melbourne 24k motorhome a
few months ago in Wisconsin. Didn't start it for 3 weeks. Now battery is dead.
What did I do wrong and what should I do now? Thanks.

[Subaru297]

I am sure someone else with motorhome experience will be along shortly but what battery is dead?

Starter battery or the house battery? Both?

All trailers and MH have parasitic draw that will kill batteries if they sit for too long. The propane and CO detectors are the usual culprits.
If you don't have the means of plugging in the MH while it is in storage you need to disconnect the house battery or it will drain.
I am not sure about the starter battery and if that will drain as well. Probably not.
Although all batteries do have a slow internal drain and will die if you leave them long enough. Even without something constantly drawing power.

Cheers

[hoppers4]

Both the house and chassis battery have a parasitic draw. If you're talking about the chassis battery you need to get a battery tender and keep it hooked up constantly while parked. If it's the house battery, you need to keep the rig plugged in or disconnect the battery with the battery disconnect switch.

[caroga]

Try charging first. If you can get them charged, the do a load test to see max and min.
If load is below 9.5 to 9, they aren't any good. Just had the same happen to my house battery on our 2016 Greyhawk. Purchased a new one and Jayco is reimbursing us.

[Wheels Rolling]

When I put my 2016 Melbourne 24k into storage, I had shut off the cabin battery disconnect via the master power switch button just inside the doorway on the left. I also made sure the front radio/entertainment screen was off "Display off". After untouched for 5 months in storage, I was pleased that it started up on the first try. However if it hadn't, I would have turned on the cabin battery switch and used the press button under the steering column which temporarily draws cabin battery to assist the engine battery for engine starting. But I didn't have to do that because it started right up.

[Gord60]

It's kinda late to respond, but I did the same thing in my 2017 Melbourne 24k. The chassis battery also powers the steps. I was constantly in and out with the power step not powered off, and they finally quit working, and I figured out where they are fed from. Now I turn them off as soon as I open the door when I park at home.