As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INSPECTION TYPE-N/A, AT CRUISE ALTITUDE FL330 NR 4 A-LOOP FIRE DETECTOR FAULT LIGHT ILLUMINATED. FIRE DETECTOR NACELLE TEMP INDICATOR WAS FLUXUATING FROM 0 TO FULL SCALE SELECTED B-LOOP AND FOLLOWED AOM PROCEDURE. RE-RACK ENGINE NR 4 A-LOOP CARDS, OPS CHECK NORMAL.