As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 3892 THE CREW REPORTED, RECEIVED A MESSAGE THAT NR 1 ENGINE FIRE BOTTLE WAS INOPERABLE. THE CREW ELECTED TO RETURN TO MIA. THE AIRCRAFT LANDED WITHOUT INCIDENT. THE AIRCRAFT WAS REMOVED FROM SERVICE. RESET SYSTEM. NO PARTS REMOVED OR REPLACED. THE OPERATIONAL CHECK WAS GOOD PER AMM 26-21-00. NO DEFECTS NOTED, OK FOR SERVICE. THE AIRCRAFT WAS RETURNED TO SERVICE.