Welcome, I am Chris (aka-Moose)
When the doors are open the circuit to the GEM is grounded. It is an open circuit when the doors are closed. You would need to unplug the GEM and test the connectors to it to see what signal the wires from the sensors are sending to determine if its a switch or wire issue or the GEM to blame. If you need a connector diagram, I have no upload that in private contact.
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