First - What year and model are you working on?
On the Excursion 35E there is a rotary switch in the basement compartment where the inverter is mounted that can be turned off - more like a disconnect - when the vehicle is in storage. This would normally be on.
Next question is does anything work when not plugged into shore power or on generator? Try an outlet near the dash passenger side or one over the kitchen counter. Not sure exactly which outlets are also wired through the inverter but some should be. Checking to see if any outlet has inverter power will tell you if its a fridge circuit problem or inverter problem.
Last - send a tech question to Fleetwood through the website. Its under Parts & Service, Ordering Parts, Contact us. They are responsive to general questions and might also be able to send you the manual for the controller you mentioned. My coach has the magnum inverter and I was able to download the manual from the magnum website. You should be able top pull the model number off the inverter itself in the basement compartment. The controller you see on the panel over the door is likely the remote control for the inverter and there should be a manual for that on the inverter site too. .
