What was found
CREW REPORTED THAT THEY RECEIVED A LAVATORY SMOKE MESSAGE ON CLIMBOUT. NO SMOKE WAS DETECTED IN THE CABIN AND NO SMOKE ODORS WERE PRESENT. THE CREW DECLARED AN EMERGENCY AND RETURNED TO FIELD. THE AIRCRAFT LANDED WITHOUT INCIDENT. NO SMOKE SMELL WAS PRESENT ON THE GROUND AND THE LAVATORY SMOKE DETECTOR WAS DEFERRED. THE DEFERRAL WAS CLEARED ON 3/9/2013 WHEN THE LAVATORY SMOKE DETECTION SYSTEMS WAS OPERATIONALLY CHECKED GOOD WITH NO DEFECTS NOTED. MAINTENANCE ALSO PERFORMED OPERATIONAL CHECKED THE BOTH ENGINE BLEED SYSTEMS AND THE COOLING PACK SYSTEM WITH NO DEFECTS NOTED.