As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLE - FLT 3961 - AFTER TAKEOFF FROM CLEVELAND, THE CREW REPORTED A LAVATORY SMOKE WARNING INDICATION. THE AIRCRAFT RETURNED TO CLEVELAND WITHOUT FURTHER INCIDENT. MAINTENANCE REMOVED AND REPLACED SMOEK DETECTOR PANEL IAW 145 EMB MM 26-14-02. MAINTENANCE ALSO REPLACED THE LAVATORY SMOKE SENSOR IAW 26-14-01. PERFORMED OPERATIONAL CHECKS IAW 26-14-00. MAINTENANCE DID NTO DETECT ANY EVIDENCE OF SMOKE. THE AIRCRAFT WAS RELEASED FOR SERVICE (M)