Is there a Kill Switch for ElD class b 12V power to camper?

I'm new here; hopefully someone is listening. Apparently because ElDorados (according to the "history" presented at another spot on this website) haven't been manufactured for a decade or more, there is a limited number of owners around any more to share advice on a decreasing inventory.

I have a (new to me) 1994 ElDorado Honorbuilt class b van camper. Everything seems to be in good shape.

My dilemma is I can't find any "kill switch" to turn on and utilize the battery 12V power for the camper functions (i.e., ceiling lights, pump, everything behind the driver seat). When I plug in an outside power source from a 110V extension cord to my house, I've got power everywhere! However, when not plugged in to 110, the 12V power does not cut in to replace it.

I bought the $5.95 operating manual on the main website, and it refers to a "kill switch" that ElDorado apparently installed which required users physically to switch to 12V (to save from inadvertently running down the batteries, apparently). The manual says that it was "on the left side of the dash" or "in the cabinet below the sink." I can't find any such switch. I can understand that such a switch would keep things like the fridge or electrical appliances inadvertently running down the van batteries. However, I suspect the technology is advanced enough that there are other ways to avoid the effect. (I talked with an owner of a 1992 class b ElD van, and he didn't have such a switch. His 12V automatically took over when no 110V line was plugged in to an outside power source.)

Any help anyone can provide I would much appreciate! I'm down here in Texas ready to go on a maiden run, but cannot do so until I can find out how to get power to the back end if I try to camp in the wild.

Thanks,

Rhinoturtle

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