As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SAT - FLIGHT 216, THE CREW REPORTED A LAV SMOKE EICAS MASTER WARNING IN FLIGHT AFTER THE AIRCRAFT HAD JUST BEEN DEICED IN OKC. THE MESSAGE CLEARED BY ITSELF, AND THE FO VERIFIED NO SMOKE IN THE LAV. THE AIRCRAFT CONTINUED TO SAT WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED THE AIRCRAFT, OPERATIONALLY CHECKED THE LAV SMOKE DETECTOR WITH NO DEFECTS NOTED, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.