As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN THE ACFT DID AN AIR TURN BACK TO THE DEPARTURE AIRPORT DUE TO THE 2L DOOR WARNING MSG COMING ON. THIS WAS A REPEAT SNAG WITH 3 PREVIOUS IN-FLIGHT DIVERSIONS TO CARRY OUT THE MEL REQUIREMENTS. AFTER EXTENSIVE TROUBLESHOOTING THE FAULT WAS TRACED TO A PUSHED BACK PIN IN CONNECTOR 3261-J14 PIN A. A NEW PIN WOULD NOT LOCK SO THE CONNECTOR WAS REPLACED. CONNECTOR PN JD38999 24WB5SN. ACFT TSN 859, CSN 570.