What was found
DURING CLIMBOUT, THE CREW FOUND THE LANDING GEAR HANDLE UNABLE TO BE MOVED, THE LANDING GEAR WAS UNABLE TO BE RETRACTED, AND A LANDING GEAR AIR/GROUND FAIL MESSAGE WAS RECEIVED. THE CREW FOLLOWED THE QRH AND DECIDED TO MAKE AN UNSCHEDULED LANDING AT THE AIRPORT OF DEPARTURE; THE LANDING WAS UNEVENTFUL. MAINTENANCE FOUND THE NLG WEIGHT ON WHEELS SWITCH TO BE FAILING AND THE ACFT WAS FERRIED UNDER SPECIAL FLIGHT PERMIT TO A MAINTENANCE BASE WITH THE LANDING GEAR LOCKED DOWN. MAINTENANCE THEN FOUND MINOR CORROSION ON THE NLG WEIGHT ON WHEELS HARNESS AND THEREFORE R & R THE HARNESS AND THE NLG WEIGHT ON WHEELS PROXIMITY SENSOR IAW AMM 32-63-02. ALL OPS CHECKS WERE GOOD AND NO FURTHER DEFECTS HAVE BEEN NOTED.