As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT#2104, BOS-LGW. (AIRCRAFT DIVERTED TO JFK) 'ENROUTE TO LGW CPDLC FAILED MSG WAS DATA LINK ASTU FAULT UNABLE TO RESET.ALSO VHF 3 SHOW --- IN FREQUENCY WIWOOW NOT DATA.VHF 3 VOIC WAS OPERATIONAL; REMOVED AND REPLACED ATSU IAW AMM 46-21-00. PERFORMED ASTU UPLOAD ALL OPS NORMAL NO FAULT FOUND.