What was found
PRIOR TO DEPARTURE, AFTER CLOSING THE MAIN ENTRY DOOR, THE DOOR ANNUNCIATOR WOULD NOT GO OUT. CYCLED DOOR OPEN & ONLY 5 OUT OF THE 6 DOOR POSITION SENSOR LIGHTS, 6 PACK, WERE ILLUMINATED RED. CREW RAN THE CHECKLIST, DE-POWERED THE AIRPLANE & DISCONNECTED THE BATTERY. WHILE ON THE PHONE WITH MX CONTROL, THE CREW POWERED THE UP ACFT & THE MAIN ENTRY DOOR WAS CYCLED CLOSED & OPEN SEVERAL TIMES. ALL 6 DOOR POSITION SENSORS WERE ILLUMINATED GREEN WITH THE DOOR CLOSED NORMAL CONDITION. ACFT DEPARTED WITHOUT INCIDENT.