What was found
ON FINAL APPROACH INTO KDTW, THE SMOKE CARGO WARNING CAME ON FOR APPROXIMATELY 16 SECONDS. THE FLIGHT CREW PERFORMED THE QRH AND BY THE TIME THE QRH WAS PERFORMED THE MESSAGE CLEARED. THE FLIGHT CREW DECLARED AN EMERGENCY AND REQUESTED CFR ASSISTANCE. AN OTHERWISE UNEVENTFUL APPROACH AND LANDING WAS MADE AT KDTW. CFR MET THE AIRCRAFT AND INSPECTED THE CARGO COMPARTMENT. THERE WAS NO SIGN OF SMOKE OR FIRE. MAINTENANCE INSPECTED, CLEANED AND TESTED THE CARGO SMOKE DETECTOR. THE AIRCRAFT WAS RELEASED FOR SERVICE.