As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE AT FL 310, THE STAB TRIM AND MACH TRIM FAIL MESSAGES DISPLAYED ON EDI. RAN QRH PROBLEM PERSISTED. ALSO ACCOMPANYING MSG AP PITCH TRIM MSG. RAN QRH, AP PITCH TRIM MSG PERSISTED UNTIL A/P DISCONNECTED. FLT 4563 DEL 41 MINS. EMERGENCY DECLARED.