As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DISCREPANCY: REFERENCE LTPR NR 5001372309-0010 AIRCRAFT WAS NOT GROUNDED AND IS IN CHECK FOR SCHEDULED MX. WHEN TESTING EPSU UNIT (10WL) FROM LEFT PASSENGER CREW DOOR, UNIT FAULT MESSAGE ILLUMINATES. REPLACEMENT OF THE EMERGENCY POWER SUPPLY UNIT (10WL)IS REQUIRED AS PER TSM TASK 33-51-00-810-030-A REV.100. PERFORMED REPLACEMENT OF EMERGENCY POWER SUPPLY UNIT (10WL) I.A.W AMM 33-51-38-000-001-A REV.100 AND AMM 33-51-38-400-001-A REV 100. PN OFF: 3214-62-10/ON:2590.