As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEVERAL TIMES AT CRUISE ALTITUDES, INTERMITTENT MASTER CAUTION WITH AUTO FAIL AND ALTN LIGHT ILLUMINATED WITH NO CHANGE IN CABIN PRESSURE. THE LIGHTS EXTINGUISHED WITHIN A FEW SECONDS. ACFT GROUNDED. ACC. FIM TASK 21-31, NR 801. NO FAULTS LOGGED NR 1 OR NR 2 DCPC. GROUND TEST OK, UNABLE TO DUPLICATE.