What was found
MOVED GEAR SWITCH (HANDLE) TO DOWN POSITION. GEAR REMAINED IN UP POSITION. CYCLED SWITCH UP THEN DOWN AND GEAR MOVED DOWN NORMAL. WHEN OPERATIONAL CHECK PERFORMED, MOVED SWITCH TO GEAR DOWN AND GEAR STAYED UP. WIGGLED SWITCH IN DOWN POSITION AND GEAR CAME DOWN. SEVERAL CYCLES WERE PERFORMED AND SWITCH WORKED ABOUT HALF OF THE CYCLES. INSTALLED NEW SWITCH AND GEAR OPERATED NORMALLY. HIGH TIME AIRCRAFT SHOULD HAVE THIS SWITCH REPLACED TO PREVENT A GEAR-UP LANDING.