As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING MX INSPECTION, FOUND THE EMERGENCY BATTERY VOLTAGE INDICATES "0" VOLTS. THE ACFT WAS REMOVED FROM SERVICE. R & R THE EMERGENCY BATTERY IAW EX WORK CARD EX-243185-RAI-10020-002. THE OPS CHECK WAS GOOD. THE ACFT WAS RETURNED TO SERVICE.