As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT IN BASE MAINTENANCE: PROGRAMMING AND TEST PANEL (PTP FIN 110RH) SHOWS AFT LEFT EMERGENCY POWER SUPPLY UNIT FAULTED/ DEGRADED. REPLACED EMERGENCY POWER SUPPLY UNIT 13WL BATTERY AND ACCOMPLISHED A SATISFACTORY PER AMM 33-51-38-400-002-A AND AMM 33-51-00-710-001-A.