As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING CLIMB-OUT AFTER AUTO-PILOT WAS ENGAGED, THE AMBER PRIMARY PITCH TRIM FAIL EICAS MESSAGE CAME ON. SECONDARY TRIM WAS SELECTED AND USED FOR REMAINDER OF FLIGHT. MAINTENANCE TROUBLESHOOTING FOUND THAT THE AUTO-PILOT TRIM ACTIVATION CAUSED FAILURE OF PRIMARY TRIM SYSTEM. CHANGED HORIZONTAL STABILIZER TRIM ACTUATOR P/N 6627401000-007.