What was found
(CAN) ON APPROACH , THE CREW SELECTED GEAR DOWN, NOSE GEAR WOULD NOT COME DOWN, AMBER AND RED CATION AND WARNING LIGHTS ON AND LOUD GRINDING NOISE IN NOSE WHEEL AREA WAS HEARD, THE CREW CARRIED OUT AN ALTERNATE GEAR SELECTION (THE ABOVE IS EXTRACTS FROM PILOT'S REPORT ) SEVERAL GEAR SWINGS COMPLETED AND WAS UNABLE TO DUPLICATE THE SNAG. SEQUENCE VALVE REPLACED FOR TROUBLE SHOOTING. SEVERAL MORE GEAR SWINGS COMPLETED WITH NO FAULT FOUND. SEQUENCE VALVE WAS SENT FOR TEAR DOWN REPORT, WILL UPDATE AS REPORT BECOME AVIALABLE.