As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 1 ENGINE B-LOOP FIRE WARNING, BOTH FIRE BOTTLES DISCHARGED. FIRE LIGHT AND BELL CAME ON THROUGHOUT FLIGHT. ENGINE MAINTAINED OIL PRESSURE. PERFORMED TEST OF A AND B LOOP NR 1 ENG. PER DC-8 M/M 26-10-0. FOUND "A" LOOP RESISTANCE TOO LOW. B LOOP RESISTANCE OK. (INSULATION). ISOLATEDTO PYLON LOOP. REPLACED PER DC-8 M/M 26-10-1. RESISTANCE NOW CHECKS