As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX FLIGHT 2309: FD ADC DATA INVALID MESSAGE ON CAPTAIN'S PFD. MAINTENANCE PERFORMED OPS TEST OF AIR DATA COMPUTER IAW MTC 6341101. RESET C/B ADV1 AND ADV2 (A7 AND A6). ALL CHECKS GOOD. AIRCRAFT PLACARD READS CAT III. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.