As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FOUND FLIGHT DATA RECORDER ULB TEST FAILED IAW AMM 23-71-03-002-001 AND 23-71-03-402-015 REV.87 REPLACED DFDR ULB AND CONDITION CHECKED NORMAL. IAW AMM 23-71-03-712-114 REV.87. PERFORMED ULB OPERATIONAL TEST AND THE RESULT WAS SATISFACTORY.