As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) PILOTS REPORT: AFTER GEAR SELECTED UP, LT MAIN GEAR DOOR REMAINED OPEN WITH AMBER ADVISORY LIGHT. CONTINUED CLIMB NOT ABOVE 185KTS, CONDUCTED AFTER TAKE-OFF CHECKLIST. QRH CONSULTED AND ACTIONED ALTERNATE GEAR EXTENSION. LINE MX CONFIRMED DEFECT AND INVESTIGATION REVEALED THE `LT GEAR DOOR CLOSED` PROX SENSOR TO BE UNSERVICEABLE. UNSERVICEABLE SENSOR REPLACED WITH A NEW ITEM AND THE INSTALLED SENSOR WAS RIGGED IAW THE ACFT MM. ACFT RETURNED TO SERVICE WITHOUT FURTHER INCIDENT.