As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: DURING THE BITE TEST OF THE EMERGENCY POWER SUPPLY UNITS FAULT MESSAGES EMERGENCY POWER SUPPLY UNIT COMMUNICATION EMERGENCY LEFT AND EMERGENCY POWER SUPPLY UNIT BATTERY FORWARD LEFT DISPLAYED. MAINTENANCE REPLACED THE BATTERY FOR THE FORWARD LEFT EMERGENCY POWER SUPPLY UNIT ABOVE THE R1 DOOR PER AMM 33-51-38. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED.