As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING BATTERY PACK CAPACITY CHECK FOUND BATTERY PACK LOW CAPACI TY ON M33405 REF HAECO NON-ROUTINE NO.9452854 -ORIGINATED BY EMP V905467 SEPC NO.B777-33-3-7019. PERFORMED BY EMP V905467,IDT BY EMP V924356.REPLACED THE BATTERY PACK ON M33405 AND TEST OK AS PER AMM 33-51-06-960-802 REV 97.