Heater Turned on in Cab, Motor Home engine shut down.

Christopher,

When asking questions about your MH, it is always helpful to know what chassis brand you have. In you case, you could have a P32 Chevy, F53 Ford or an Oshkosh/Freightliner.
Always start with the simplest and lest expensive items when trouble shooting.
As previously suggested, check all battery cable connections and the battery its self.

Richard