As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT#187, BOS-LAX. (ETOPS) 'ENG 2 FIRE LOOP A FAULT ( ENGINE FIRE DETECTION SYSTEMS 1) LOOP A ); UPON VISUAL INSPECTION OF ENG # 2 LOOP A HI-TEMP FIRE DETECT 4181KS, FOUND BREAK ON CABLE ASSY. REMOVED AND REPLACED LOOP A FIRE DETECT IAW AMM 26-12-61. NO FURTHER FAULTS NOTED AT THIS TIME. FDU'S TEST PASSED. THIS CLEARS MDDR# 502416. PLACARD REMOVED. MX-4 UPDATED. MCC NOTIFIED