As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER SEAT ROW 21, 2 2, AND 23 ABC INSTALLATION EMERGENCY LIGHTS WILL NOT TEST ON ROW S 10 THRU 20. PERFORMED TS. FOUND BATTERY PACK M1676 DEFECTIVE. AT ROW 7 DEF REMOVED AND REPLACED ATTERY M1676 REF AMM 33-51-06 ALL CHECKS GOOD AT THIS TIME