What was found
DURING CLIMBOUT FROM CMH, NOSE AND MAIN LANDING GEAR RED UNSAFE LIGHTS REMAINED ON AFTER GEAR WAS RETRACTED. RECYCLED GEAR WITH NO HELP. APPROXIMATELY ONE HOUR INTO FLIGHT, A 'CLICK' WAS HEARD AND ALL THREE RED UNSAFE LIGHTS EXTINGUISHED. FLIGHT CONTINUED TO DESTINATION (MSP) AND LANDED WITHOUT INCIDENT. JACKED AIRCRAFT AND SWUNG GEAR SEVERAL TIMES. DISCREPANCY COULD NOT BE DUPLICATED. REPLACED PROXIMITY CONTROL UNIT AS A PRECAUTION.