As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT#723, JFK-LAX. (ETOPS) 'ENG 2 FIRE LOOP A FAULT ( ENGINE FIRE DETECTION SYSTEMS 1) LOOP A ); T/S REF MDDR 548311. ACCOMPLISHED TSI FOUND #2 ENG LOOP A AGB DET WITHIN LIMITS FOR RESIST AND INSULATION CHKS. ALSO FOUND NO FAULTS WITH HARNESS FOR #2 ENG A LOOP AGB DET. PER TSI REQUEST REMOVED AND REPLACED AGB DET 4002WDI FOR #2 ENG REF AMM 26-12-17. #2 ENG FIRE DET SYS OPS CHK NORMAL. RAN #2 ENG AT IDLE FOR NEW PFR. PFR REPORTED NO FAULTS. THIS CLEARS MDDR 548018.