As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON PREFLIGHT EMERGENCY POWER TEST FAILED AFTER ABRUPT POWER LOSS AND REINSTATEMENT. "ADG BATTERY CTL RLYINTFC" IN CFDS MESSAGE. POWERED DOWN AND WAITED FOR BATTERY TO BE CHARGED. EMERGENCY POWER TEST PASSED IAW MM 24-34-02-5. ACFT OK FOR SERVICE.