As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EWR---CO3443/MX, CREW REPORTED AFTER TAKEOFF FROM DAY, LAV SMOKE MASTER WARNING ON CLIMBOUT. AIRCRAFT RETURNED TO DAY. AIRCRAFT INSPECTED AND RELEASED IAW MEL. AIRCRAFT RETURNED TO SERVICE. UPON ARRIVAL IN NEWARK MAINTENANCE CLEANED SMOKE DETECTOR SENSOR IAW EMB135/145 AMM 26-15-00. OPS CHECKED SYSTEM GOOD. AIRCRAFT RETURNED TO SERVICE.