As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
"AUTO FAIL" LIGHT AT FL 390 (REPEAT) ALTN=NORM PRESS CABIN CONTROL UNABLE TO DUPLICATE. ACCOMPLISHED FAULT HISTORY PRESENT STATUS AND GROUND TESTS BOTH 1 AND 2 DCPS OPS CHECK NORMAL. REMOVED AND REPLACED P5 6 CABIN PRESSURE CONTROL MODULE AS PRECAUTION PER MM 21 31 02.