As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
"FIRE DET 1 FAIL" LEVEL 1 ALERT DURING CRUISE FLIGHT. INTERROGATED #1 FDCU. FOUND #1 ENG. UPPER RIGHT TURBINE A LOOP FAULTED. WITH B LOOP ALREADY DEFERRED. REMOVED AND REPLACED #1 ENG. UPPER RIGHT TURBINE A LOOP AND HARNESS BETWEEN DH4 AND DH23. FDCU RTS PASSES AND #1 ENG FIRE TESTS GOOD.