What was found
ON APPROACH, PILOT SELECTED THE LANDING GEAR HANDLE TO THE EXTEND POSITION, PILOT DID NOT RECEIVE 3 DOWN AND LOCKED INDICATOR LIGHTS. PILOT DECIDED TO PERFORM A MANUAL EXTENSION OF LANDING GEAR; PILOT RECEIVED 3 GREEN DOWN AND LOCKED INDICATOR LIGHTS AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE TROUBLESHOOTING REVEALED A FAULTY LT LANDING GEAR DOWNLOCK SWITCH, MAINTENANCE REPLACED DOWN LOCK SWITCH AND PERFORMED LANDING GEAR SWINGS, LANDING GEAR OPS CHECKS NORMAL.