Typically, the door controls just tell how to dispense ice on demand. The maker makes it whether you use the dispenser or not. The "lock" button on the front is to keep little kids from making a mess.

Our old ice maker used the wire to set to "off"; our new one has an electric on/off rocker switch - albeit one that's often slightly frozen in place and needs a bang to get it to change.

If you disconnected the water feed to the maker, did you plug the hose/hole in the back of the box? That might be letting moisture in.

Ultimately, I'm thinking the self defroster isn't working properly.