What was found
(CAN) DURING NORMAL APPRAOCH, CREW EXTENDED LANDING GEAR BUT DID NOT GET A NOSE GREEN. GEAR WAS CYCLED WITHOUT CHANGE. EMERGENCY PROCEDURES PROVIDED FOR MANUAL EXTENSION BUT STILL WITHOUT GREEN. DUE TO SYSTEM WIRING, THE GEAR WAS ASSERTAINED DOWN DUE TO THE ABSCENCE OF A RED HANDLE LIGHT WHICH FUNCTIONED NORMALLY. THE GREEN AND RED LIGHTS FUNCTION OFF A DOUBLE POLE SWITCH PROVIDING SOME ASSURANCE OF ACTUAL GEAR POSITION DURING MALFUNCTIONS. DURING TROUBLESHOOTING, THE GEAR FUNCTIONED NORMALLY WITH ALL LIGHTS OPERATING PROPERLY, HOWEVER, THE NOSE GEAR ACTUATOR WAS REPLACED FOR PRECAUTIONARY REASONS AND THE AIRCRAFT RELEASED AFTER NUMEROUS GEAR CYCLES.