As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AV SMOKE ALARM ON TAXI OUT. ACFT SUFFERED RAIN INGRESSION, DRIED OUT COURIER AREA AND AVIONICS BAY AREA. VERIFIED THAT FLOOR AND DRIP PAN DRAINS ARE CLEAR AND DRAIN NORMALLY. REMOVED AND REPLACED AVIONICS DUCT SMOKE DETECTOR 13WA PER AMM 26-15-12-4. PERFORMED SATISFACTORY OPS CHECK PER AMM 26-15-00. OK FOR CONTINUED SERVICE.