What was found
IAH- AFTER TAKEOFF FLIGHT 3671, THE CREW NOTED THAT SYSTEM NR 2 LANDING GEAR UNLOCK LIGHT ILLUMINATED. MAINTENANCE INSPECTED THE AIRCRAFT AND FOUND THE LEFT MAIN LANDING GEAR UPLOCK BOX CANNON PLUG TO BE CONTAMINATED. MAINTENANCE CLEANED THE AFFECTED PLUG, PERFORMED A SUCCESSFUL OPERATIONAL CHECK OF THE LANDING GEAR, AND APPROVED THE AIRCRAFT FOR RETURN TO SERVICE.