As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: DURING TESTING OF EMERGENCY POWER SUPPLY UNIT 11WL FAULT MESSAGE WAS NOTED. REPLACED EMERGENCY POWER SUPPLY UNIT 11WL (AALA202207271343) AND BATTERY (AALA202207276877) PER AMM 33-51-38. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED.