As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FINAL TO ORD WITH FLAPS AT 9 DEGREES AND SPEED BRAKES TRANSFERRING OPEN TO CLOSE, RECEIVED EICAS MESSAGE PITCH TRIM MAIN INOP AND PITCH TRIM BACK UP FAIL. CHECKLIST PROCEDURES FOLLOWED AND MESSAGE CLEARED. REPLACED HORIZONTAL STABILIZER CONTROL UNIT. OPERATIONAL CHECK GOOD. AIRCRAFT RETURNED TO SERVICE. (M)