Weird electrical problem

[charlesE]

I have a 1998 33' gas land yacht. My electrical problems are as follows: the coach and vehicle batteries go dead unless I keep a battery charger connected to them when not using the motor home. Problem 2. I can not get the step light or patio light to go off unless I disconnect all batteries. When I press the patio light switch the fantastic fan motor cuts on for about 1 second and turns off. The patio light and step light are unaffected by anything except disconnecting the batteries. The patio light and stair light only started to stay on today, the dead battery problem is on going. Are these problems related and where do I start in solving these problems.

[Lumatic]

I would start with a load test on the batteries. How old are they? Then I would disconnect one circuit at a time and see if the the batteries still go dead.

[garry]

I suspect you have a switch to turn the steps off, as long as the steps are "on" the controller is drawing current in addition there are many parasitic loads such as the CO detector, radio, frig etc.

You also have a battery cutoff switch that disconnects the batteries while in storage that needs to be turned off when parked without power for more than a week or so.