As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED AND IS IN CHECK FOR SCHEDULED MX. DURING INCOMING CHECKS FOUND EPSU BATTERY 10WL INOP REPLACEMENT REQUIRED IAW AMM 33-51-38-400-002-A REV. 102. REPLACED EPSU BATTERY 10WL AMM 33-51-38-400-001 CONF 00 REV 102. MX ACTION IS ACCEPTABLE.