As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE FIRE LP 2 DISPLAYED, RT ENGINE. SWAPPED CONTROL CARDS M683, M684 RT ENGINE FIRE LOOP 1 AND 2 FOR TROUBLESHOOTING PER GMM CHAP 8. P/N'S FOR BOTH CARDS ARE S332T301-181. NEW S/N FOR M683 IS 21788, NEW S/N FOR M684 IS 21781. BOTH CARDS OPS CHECK GOOD. (M)