As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TEST FOUND ERROR MSG "EPSU BATTERY EMER L" ATA 33-51-38 SEE PIC REMOVED AND REPLACED LEFT OVERWING EMERGECNY EXIT LIGHT POWER SUPPLY BATTERY REF AMM 33-51-38/401. OPS CHECK GOOD, BITE TEST PASSES WITH A GREEN SYS OK LIGHT AND NO FAULTS.