As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER BLOCK OUT ON TAXI, RECIEVED DATA LINK LOSS MESSAGE. RAN QRH 5.1 AND CONSULTED MAINT DISCREPANCY FLOWCHART. RETURNED TO THE GATE (BTB). DEFERRAL CPDLC SAT COM DATA LINK IAW B767 MEL 23-25-1-8B NO MX PROCEDURES REQUIRED PLACARD INSTALLED MBCB 10/28/2026 NO FURTHER DEFECTS NOTED. A/C RETURNED TO SERVICE.