What was found
(CAN) NOSE GEAR TRANSIT LIGHT ILLUMINATED WHEN GEAR SELECTED DOWN. CREW CYCLED GEAR A COUPLE OF TIMES WITH NO RESULTS. A VISUAL CHECK THROUGH FLOOR HOLE VIEWER ATTEMPTED. NOSE GEAR VIEWER HARD TO DETERMINE VISUAL ON RED LINES FOR A LOCKED CONDITION.THE CREW OPTED TO RETURN TO STATION OF ORIGIN WITH AN UNEVENTFUL LANDING. THE A/C WAS FERRIED TO THE MAIN BASE FOR MAINTENANCE. MAINTTENANCE TESTED AND CONSEQUENTLY REPLACED THE NLG DOWN LOCK SENSOR. AS A PRECAUTION THE NLG VIEWER WAS CLEANED AND THE DOWNLOCK INDICATOR ARROWS WERE REPAINTED.