As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA FLIGHT NR 2019: WX FAIL IN CRUISE. CYCLED OFF PER MTX. MFD SHOWED MESSAGE IN ALL POSITIONS. AIRCRAFT RETURNED TO FIELD. MAINTENANCE REMOVED AND REPLACED THE WEATHER RADAR TRANSCEIVER PER Q400 AMM 34-41-01, PG 401-406. OPS CHECK GOOD. NO WX FAIL MESSAGE SHOWN. AIRCRAFT RETURNED TO SERVICE.