What was found
AFTER SWITCHING EMER POWER TO ARM DURING PREFLIGHT, WE RECEIVED A LEVEL ONE, EMER PWR TST FAIL, ALERT. CYCLED BATTERY CHARGER CB'S & PERFORMED RTS OF EPCU IAW AMM 24-08-01-5. ALL CHECKED NORMAL AT THIS TIME. PERFORMED EMER POWER TEST IAW AMM 24-24-00-5. OPERATIONS CHECKED NORMAL AT THIS TIME. ACFT OK FOR CONTINUED SERVICE.