As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING HEAVY MAINTENANCE: REF AEROMAN WO# 2025 189/1. NR# 2025-397167. EPSU 13WL ( EMERGENCY POWER SUPPLY UNIT ) IN PAX CABIN FAILS OPERATIONAL TEST; (RESOLVED ON W/O: 1396919 TASKCARD: NR-00043) REF AEROMAN WO# 2025 189/1. NR# 2025-397167. REMOVED AND REPLACED EPSU 13WL (EMERGENCY POWER SUPPLY UNIT ) IN PAX CABIN IAW TSM 33-51-00-810-822-A, AMM 33-51-38-000-001-A, AMM 33-51-38-400-001-A. PERFORMED OPERATIONAL CHECK OF THE EPSU THROUGH BITE CHECK, TEST IS OK.