As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: FLIGHT ATTENDANT REPORTS OVERWING EXIT LIGHTS AT DOOR 2R ARE ILLUMINATED INFLIGHT. MAINTEANCE REPLACED EMERGENCY POWER SUPPLY UNIT 15WL BATTERY AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK PER AMM 33-51-38.