Please, do not leave the coach batteries in a discharged condition. Whatever you do, do something to get the batteries charged. You will need to bring the charging power to the batteries or the batteries to the charging power.
If you have a charger and an A/C source of power, the easiest thing to do would be to use the charger to charge up the coach batteries. Check the water, in the batteries, before you charge them.
If you have a charger, but no A/C source of power, consider taking the coach batteries out of the coach, to a place where they can be charged. Because you are winterizing the coach, maybe you could leave them out of the coach for this winter? After charging the batteries, let them sit disconnected for a week. Check each cell with a hydrometer to ensure the batteries are still good. Even with a new coach, you could easily have an internal short or dead cell. Do not let the batteries sit on the ground or on concrete for any length of time.
For my Newmar coach, when I turn the coach disconnect switch to off, everything is really off. Yours may be different. After this is all sorted out, consider running some tests, once you get fully charged coach batteries in the coach. You either have a draw, even when the switch is off or a bad battery(s).
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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