Called Thor this morning and explained my problem . Tech on phone says "that's impossible " and that the rv will not start with the positive side of the chassis battery disconnected.
He also said to let them know if I figured out the problem
He did identify the solenoid as being located in the engine compartment by the windshield washer bottle.
Went out to the rv and checked the solenoid with a test light , both sides are hot with the crossover (emergency start switch) at rest.
Called Thor back to get a part number for the solenoid , they are having trouble finding it.
They were very nice and said they will find it and call me back.
Guess I'll pull the solenoid off and see what markings are on it.