As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: EMERGENCY POWER SUPPLY UNIT BATTERIES AT LOCATIONS 11WL FAILED BUILT IN TEST EQUIPMENT TEST IN REFERENCE WITH JOB CARD 26L00005005. REMOVED AND REPLACED 11WL, EMERGENCY POWER SUPPLY UNIT BATTERY IN REFERENCE WITH AMM 33-51-38.