As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PS-1 CHECK FOUND BOTH AFT OVER THE WING EMERGENCY LIGHTS NOT WORKING. C/A-REMOVED AND REPLACED NR 4 EMERGENCY BATTERY PACK AND POWER SUPPLY IAW AMM 33-50-04, OPS CHECK IAW AMM 33-50-00-700-801-A. OPS CHECK GOOD. EMERGENCY LIGHTING BATTERY P/N 2013-1ASMI S/N 798326.