As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING HEAVY CHECK EPSU UNIT 10WL FAILED PTT & SYSTEM TEST. FLAGGED UNIT FAULT. FAULT HAPPENED DURING A SCHEDULED RON MAINTENANCE VISIT & DID NOT CAUSE A FLIGHT DELAY. IAW AMM 33-51-38-000-A, & 33-51-38-400-001-A, REMOVED AND REPLACED EPSU UNIT 10WL PIT TEST, EPSU & CIDS POWER-UP TESTED OK. NO OTHER DEFECTS NOTED. ACFT OK FOR SERVICE.