As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE EN ROUTE, THE CREW RECEIVED A RED WARNING PANEL MAIN CABIN DOOR LIGHT ON. THE CREW CONSULTED THE QUICK REFERENCE HANDBOOK AND NOTIFIED DISPATCH THAT FLIGHT 4081 WOULD DIVERT AND LAND AT CHARLESTON. MAINTENANCE CONTROL HAD OUTSTATION MAINTENANCE CLEAN THE MAIN CABIN DOOR PROXI SWITCH IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 52-00-00. OPERATION CHECKS WERE PERFORMED AND THE AIRCRAFT WAS RELEASED FOR SERVICE.