As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: PERFORMED OPERATIONAL TEST OF EMERGENCY LIGHTS PER JOB CARD 26L00005005, TEST FAILED, AFT LEFT EMERGENCY POWER SUPPLY UNIT FAULT. REMOVED FAULTY EMERGENCY POWER SUPPLY UNIT 13WL FROM AFT GALLEY CEILING AND INSTALLED NEW EMERGENCY POWER SUPPLY UNIT PER AMM 33-51-38.