As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: CIDS EMERGENCY POWER SUPPLY UNIT SYSTEM TEST DISPLAYED FAULT MESSAGE FOR EMERGENCY POWER SUPPLY UNIT 11WL. MAINTENANCE REPLACED EMERGENCY POWER SUPPLY UNIT 11WL BATTERY PER AMM 33-51-38. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED.