What was found
AIRCRAFT FAILED TO SHIFT FROM GROUND MODE TO FLIGHT MODE AFTER TAKEOFF. ALSO, NOSE LANDING GEAR UNSAFE LIGHT ILLUMINATED. FLIGHT WAS RETURNED TO MSP AND LANDED WITHOUT INCIDENT. INDICATIONS RETURNED TO NORMAL AFTER GEAR WAS EXTENDED FOR LANDING. MAINTENANCE FOUND NOSE LANDING GEAR STRUT DEFLATED. REPLACED NOSE STRUT SEALS AND SERVICED STRUT TO PROPER LEVELS, OPERATIONAL CHECK NORMAL.