As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SLAB BATTERY WOULD NOT STAY CHARGED AFTER BEING REPLACED SEVERAL TIMES. TROUBLESHOOTING REVEALED THE FA5001 CVFDR HAD A CONTINUOUS DRAIN ON ACFT SLAB BATTERY, EVEN WHEN SYSTEM WAS TURNED OFF. REMOVED AND REPLACED CVFDR IAW AMM 31-32-00, 4-1.