As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING APPROACH THE CHECK FIRE DETECTOR MASTER WARNING ILLUMINATED ALONG WITH THE MASTER WARNING LIGHT. MAINTENANCE INSPECTED THE AIRCRAFT FIRE LOOPS 1 AND 2, THE 1 AND 2 ENGINE DETECTORS, FORWARD BAGGAGE, AND APU FIRE DETECTOR SYSTEMS. ALL SYSTEMS CHECKED GOOD AND THE AIRCRAFT WAS RETURNED TO SERVICE.