As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT#1620, BOS-LHR. (ETOPS) 'FUEL ACT XFR FAULT ( AUTO TRANSFER SYSTEM (ACT) 1), 2) ADDITIONAL CENTER TANK(S) (ACT). ACCOMPLISHED OPERATIONAL TEST OF THE ACT AUTOMATIC TRANSFER SYSTEM PER AMM 28-28-00-710-005A. FUNCTIONS NORMAL. NO DEFECTS. MDDR CLEARED. MX-4 UPDATED. PLACARD REMOVED.