As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A TURN AROUND CHECK THE EMERGENCY ESCAPE PATH LIGHTING FROM ROW 30 TO 34 WAS FOUND TO BE INOPERATIVE. MAINTENANCE FOUND THE ASSOCIATED BATTERY PACK TO BE DEFECTIVE AND REPLACED IT. SYSTEM OPERATION WAS NORMAL AFTER THE BATTERY PACK WAS REPLACED.