As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CHECK FIRE DET MASTER WARNING LIGHT ILLUMINATED IN FLIGHT WITH ASSOCIATED NR 1 FAULT A AND FAULT B LIGHTS ILLUMINATED. R & R FIRE CONTROL AMPLIFIER IAW AMM 26-10-01-000-801 AND 26-10-01-400-801. C/W OP TEST OF NACELLE FIRE DETECTION SYS, BAGGAGE SMOKE DETECTORS, APU FIRE DETECTION SYS, AND OP CHECK OF THE FUEL AND HYD SHUTOFF VALVES. ALL SYS OP TEST GOOD. MASTER WARNING CHECK FIRE DET & NR 1 FAULT A & B LIGHTS EXTINGUISHED. RETURNED TO SERVICE.