As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PERFORMED EPSU TEST AND 12WL & 13WL FAULTED ON THE TEST. AC WAS NOT GROUNDED AS A RESULT OF THIS SDR REPORTABLE EVENT, AC WAS ON SCHEDULED MX.. REMOVED AND REPLACED THE EPSU BATTERY ON POSITIONS 12WL & 13WL PER AMM REF 33-51-38-000-002-A AND 33-51-38-400-002-A. PERFORMED OPS CHECK. OPS CHECK GOOD. AC OK FOR SERVICE. /END/.