As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 1 PFD WENT BLANK FOLLOWED BY A NR 1 YAW DAMPER DISCONNECT AND AUTO PILOT DISCONNECT. BOTH RE-ENGAGED. REMOVED AND REPLACED NR1 PFD IAW 31-61-4. OPS CHECK GOOD. RETURNED TO CAT II. REMOVED AND REPLACED NR 1 DCU FOR NUMEROUS DCU FAILS IN MDC IAW 31-41-04. PFD P/N: 622-9810-016, S/N OFF: 10DRR.