What was found
(CAN) ON APPROACH THE CREW NOTED THE NOSE GEAR INDICATOR FOR DOWN & LOCK DID NOT ILLUMINATE. THEY ABORTED THE APPROACH & DID A FLY BY THE TOWER TO VERIFY THE GEAR WAS DOWN & LOCKED. TOWER CONFIRMED IT APPEARED DOWN & THEY CAME AROUND TO LAND. ON FINAL THE LIGHT CAME ON & REMAINED ON FOR THE LANDING & TAXI TO THE HANGAR. TROUBLESHOOTING THE SYS IT WAS NOTED THAT THE CONFIGURATION OF THE LENSES FOR THE POSITION INDICATION WAS WRONG & NOT AS IT SHOULD BE FROM LT TO RT. THE INDICATION SHOULD BE LT, NOSE, RT & THE POSITION OF THE LENSES WAS LT, RT, NOSE. FURTHER TROUBLESHOOTING REVEALED THAT IN FACT THE RT MAIN GEAR DOWN & LOCKED SWITCH WAS INTERMITTENT ON MAIN GEAR ACTUATOR, PN 25W252005-508. THE LENS HAD BEEN SOMEHOW CHANGED PRIOR TO OPERATING THE ACFT & NO ONE HAD NOTICED THE LOCATIONS WERE WRONG AS THE WRITING IS QUITE SMALL. AT A GLANCE EVERYONE SIMPLY LOOKED FOR THREE GREEN. SWITCH PN MM8805 100-016, HAS BEEN REPLACED & GEAR SWINGS CARRIED OUT & SYS FUNCTIONED NORMAL.