As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING B INSPECTION, FOUND THE LEFT AFT EXTERNAL OVERWING EXIT EMERGENCY LIGHT INOPERATIVE. AIRCRAFT REMOVED FROM SERVICE. REMOVED AND REPLACED THE NR 4 BATTERY POWER SUPPLY IAW AMM 33-50-04 AND PERFORMED OPS CHECK IAW AMM 33-50-00. OPS CHECKED GOOD. AIRCRAFT RETURNED TO SERVICE.