What was found
DURING APPROACH INTO DTW, NOSE LANDING GEAR UNSAFE LIGHT REMAINED ON AFTER GEAR EXTENSION. FLIGHT CREW DECLARED A YELLOW EMERGENCY AND ALTERNATE GEAR EXTENSION PROCEDURES WERE UTILIZED FOR LANDING. MAINTENANCE FOUND BROKEN NOSE GEAR PROXIMITY SENSOR. ALSO, REPLACED LEFT MAIN GEAR DOOR SKID PLATE DUE TO DAMAGE INCURRED ON LANDING. OPERATIONAL CHECK NORMAL ON GEAR SWING. AIRCRAFT RETURNED TO SERVICE.