As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
OFAR BACKUP LIGHT POWER SUPPLY TEST FOUND THE BATTERY PACK(M3314 3) CAN NOT BE CHARGED REF TO HAECO NON-ROUTINE NO.9459962, ORIGI NATED BY EMP V907748, SPEC NO.B777-33-3-7005. PERFORMED BY EMP V907748 AND IDY BY EMP V903172 - REPLACED THE B ATTERY PACK M33143 IN THE OFAR PERFORMED INSTALLATION TEST. THE RESULT WAS NORMAL REF AMM 33-51-06-960-802 REV 98.