As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT IN BASE VISIT: MAINTENANCE REPORTS INOP EPSU-EMERGENCY POWER SUUPLY UNIT (10WL) BATERY IN PASSENGER CABIN. REPLACED BATERY OF THE EPSU 10WL IAW AMM 33-51-38-400-002-A IN PASSENGER CABIN 1E/A AND PERFORMED OPERATIONAL TEST OF THE EMERGENCY POWER SUPPLY UNIT IAW AMM 33-51-00-710-001-A. TEST IS OK.