What was found
(CAN) THE AIRCRAFT WAS ON APPROACH AND THE NOSE GEAR GREEN LIGHT DID NOT COME ON, BOTH MAINS INDICATED GREEN.THE GEAR WAS EXTENDED MANUALLY WITH THE HAND PUMP AND A N UNEVENTFUL LANDING CARRIED OUT. MAINTENANCE FOUND THE HYDRAULIC POWERPACK WAS NOT RUNNING DUE TO AN UNSERVICEABLE MOTOR RELAY R601. THE RELAY WAS REPLACED AND THE SYSTEM FUNCTIONED PROPERLY. THE 974.09.26.112 RELAY IN QUESTION HAS BEEN FAILING IN THE PAST. THIS IS THE 3RD INSTANCE THE SAME PART NUMBER RELAY HAS FAILED, EITHER OPEN OR CLOSE. ONE PRIOR TO THIS FAILED OPEN AND WOULD NOT ALLOW THE PUMP TO RUN, AND THE ONE PRIOR TO THAT FAILED CLOSED AND THE PUMP RAN CONTINUOUSLY. PILATUS HAS BEEN NOTIFIED VIA A DEFECT REPORT.