As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER DEPARTURE, NR 2 ENGINE FIRE LIGHT ILLUMINATED. THERE WAS NO SMOKE VISIBLE, NO SMELL, AND NO ERRATIC ENGINE INDICATIONS. ACFT RETURNED FOR UNEVENTFUL LANDING. FIRE DETECTOR AMPLIFIER WAS REPLACED. SYSTEM OPS CHECK AND TEST OKAY. AWAITING DETAILS FROM REPAIR FACILITY ON AMPLIFIER DEFECTS.