For others, yes it works off the coach battery. You have parasitic drains that may run your chassis battery down if it is not up good to start with. Remember it comes with all these computers that are still running. You radio might be hooked up to the chassis battery some are some aren't. When you say for a week, is that storage or is it plugged in with shore power. Lots of things to check as well as the solenoid. What year and model is your RV?
2015 Four Winds Super C 33SW, w 6.7 Diesel 300HP - 660 lbs of torque
2011 Jeep Wrangler Sport as towed vehicle
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