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 THE ACCOMPLISHMENT OF THE EMERGENCY POWER SUPPLY UNIT CIDS 1 TEST A FAULT MESSAGE FOR EMERGENCY POWER SUPPLY UNIT 11WL DISPLAYED. MAINTENANCE REPLACED EMERGENCY POWER SUPPLY UNIT 11WL PER AMM 33-51-38 AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK.