As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TRANSIT CHECK PAT WENT OFFLINE - ON P6 PANEL APU FIELD GEN LIGHT ILLUM NUMEROUS COCKPIT LIGHTS WERE OUT. CORR T/S TO MAIN BATTERY, BATTERY AT 20VDC WITH NO LOAD ON IT. REMOVED AND REPLACED BATTERY PER MM, EVERYTHING RESET AND CHECKS GOOD.