As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE ON APPROACH, ALL 3 GEAR INDICATIONS WERE RED "UNSAFE". THE CREW PERFORMED A MANUAL GEAR EXTENSION AND LANDED WITHOUT FURTHER INCIDENT, OTHER THAN THE GEAR DOORS BEING OPEN ON LANDING. MAINTENANCE FOUND ALL POSITION/WARNING SENSORS AND THE DIMENSIONAL LIMITS OF THE PROXIMITY SENSORS WERE WITHIN AMM LIMITS. THE GEAR WAS SWUNG WITH NO DEFECTS. MAINTENANCE REPLACED THE PSEU.