As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT#1107, JFK-LHR. (ETOPS)' CLASS II MAINTENANCE MESSAGE AC GEN DISPLAYED ON POWER UP ( CLASS II MX MSG - GPCU OR AC GEN ). PERFORMED OPS TEST OF GCU 1 AND GCU 2 IAW AMM 24-22-34. THE OPS CHECK IS GOOD. NO MSG DISPLAYED AT THIS TIME. NO PREVIOUS HISTORY. MDDR CLEARED. MX-4 UPDATED. PLACARD REMOVED.