As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED WHEN CLIMBING FROM FL030 TO FL040, THEY RECEIVED A SMOKE CAUTION MESSAGE. THE CREW DECLARED AN EMERGENCY, RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. MAINTENANCE TROUBLESHOT, R & R LT PACK COALESCER BAG. MAINTENANCE PERFORMED OPS CHECKS IAW AMM AND RELEASED ACFT FOR SERVICE.