As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT APPROXIMATELY 16,000 FT, RECEIVED A WARNING LIGHT FOR L1 DOOR. PRESSURIZATION NORMAL AND F/A VERIFIED THE DOOR SECURE. RETURNED TO DEPARTURE. AN EMERGENCY WAS NOT DECLARED AND LANDED WITHOUT INCIDENT. MAINTENANCE R & R THE CLOSED DOOR SENSOR AND PERFORMED RIG OF DOOR AMM. DOOR OPS CHECKED GOOD AND ACFT IS GOOD FOR SERVICE.