What was found
WHILE THE AIRCRAFT WAS IN FLIGHT, THE FLAPS FAILED TO EXTEND TO THE SELELCTED APPROACH POSITION. THE PILOT CYCLED THE FLAP SELECT SWITCH TO UP AD BACK TO APPROACH AND THE FLAPS EXTENDED. MAINTENANCE INVESTIGATED THE REPORTED PROBLEM AND WAS ABLE TO DUPLICATE THE PROBLEM ON THE GROUND. WHEN THE FLAPS WERE SELECTED TO APPROACH THE FLAPS MOVED APPROXIMATELY 5 DEGREES AND QUIT MOVING. AFTER ACCESS WAS GAINED TO THE FLAP MOTOR/GEARBOX AND RELAY, A TAP ON THE RELAY RETURNED THE FLAPS TO NORMAL SELECTOR SWITCH RESPONSE OPERATION. INSTALLATION OF A REPLACEMENT RELAY SOLVED THE PROBLEM. THE (FAILED ) RELAY HAD 69.0 HOURS. (WP19200503541)