What was found
AFTER DEPARTURE AND CLIMBING THROUGH FL 180 THE CABIN DOOR ANNUNCIATION LIGHT ILLUMINATED. CREW RAN THE APPROPRIATE CHECKLIST AND REQUESTED A DESCENT TO A LOWER ALTITUDE IN THE EVENT THE DOOR LOST PRESSURE OR OPENED. CREW DECLARE AN EMERGENCY FOR PRIORITY HANDLING AND RETURNED TO DEPARTURE. ACFT MADE AN OVERWEIGHT LANDING WITHOUT INCIDENT. MX PERSONNEL PERFORMED AN OVERWEIGHT LANDING INSPECTION WITH NO DEFECTS NOTED AND RERIGGED FORWARD AND AFT UPPER DOOR LATCH SWITCHES. A GROUND OPS CHECK PERFORMED SATISFACTORY AND ACFT RETURNED TO SERVICE.