As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING EMERGENCY LIGHTS TEST T/C 78233001, THE INTERIOR LIGHTS AT ALL 4 OVER WING EXITS FAIL TO REMAIN ILLUMINATED FOR FIFTEEN MINUTES. ACFT GROUNDED. REPLACED OVERWING EXIT BATTERY PACKS, M1695 AND M1694 AND OPS CHECKED GOOD IAW AMM 33-51-06-960-805.