As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 3 FIRE LIGHT ILLUMINATED WITH BELL AT FL 290. AFTER SWITCHING ESSENTIAL POWER, LIGHT AND BELL WENT OUT NEVER TO COME ON AGAIN. NEVER ANY INDICATION OF FIRE VISUALLY INSPECTED NR 3 ENGINE AND FIRE LOOP. LOOKED GOOD, OPS CHECKED GOOD.