As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT IN BASE MAINTENANCE: DURING EMERGENCY LIGHT OPERATIONAL CHECK MAINTENANCE FOUND EMERGENCY POWER SUPPLY UNIT 13WL WITH UNIT FAULT LIGHT ON. REPLACED EMERGENCY POWER SUPPLY UNIT 13WL AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK PER AMM 33-51-38.