As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS IN BASE MAINTENANCE: INOP EMERGENCY POWER SUPPLY UNIT (11WL). REMOVED AND REPLACED EMERGENCY POWER SUPPLY UNIT (11WL) I.A.W AMM 33-51-38-000-001-A, AMM 33-51-38-400-001-A, PERFORMED BITE CHECK OF EPSU I.A.W AMM 33-51-00-710-001-A BITE CHECK IS OK, PERFORMED POWERUP TEST OFTHE CIDS I.A.W AMM 23-73-00-740-005-A TEST IS OK.