As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LVL 3 CABIN SMOKE ALERT. COMPLIED WITH QRH. A MID-CABIN SMOKE DETECTOR TRIANGLE FLASHED ON AND OFF DURING EVENT. ALERT WAS OUT DURING LANDING. FSS DID NOT ACTIVATE. REMOVED AND REPLACED THE MAIN CABIN #5 SMOKE DETECTOR IAW AMM 26-15-01-4. ALL SMOKE DETECTORS OPS CHECKED NORMAL IAW AMM 26-14-01.