As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT IN BASE MAINTENANCE: EMERGENCY POWER SUPPLY UNIT 15WL FAILED SYSTEM TEST. **ORIGINAL REPORT WAS AALA202311060761: MAINTENANCE REPLACED EMERGENCY POWER SUPPLY UNIT 15WL AND BATTERY (AALA202311204628) PER AMM 33-51-38. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED.