As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMBING BETWEEN FL360 AND FL380 ON AUTO PRESSURE MODE CONTROLLER KEPT DESCENDING. SELECTED ALT AND IT STABILIZED. ON DESCENT FROM FL360 TO GRND IT WORKED IN AUTO. UNABLE TO VERIFY DEFECT. NO EXISTING FAULTS IN NR 1 & 2 DCPC. NO FAULTS IN NR 1 & 2 DCPC FAULT HISTORY FOR THE LAST 40+ FLIGHTS. FOLLOWED FIM 21 31 TASK 801 NO FAULTS FOUND. VERIFICATION FLIGHT SUCCESSFUL. NO HISTORY 90 DAYS.