As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK DUE TO CAPTAIN`S TRIM CONTROL INOPERATIVE. ALTERNATE TRIM & FIRST OFFICER TRIM WORKED NORMAL, AUTOPILOT 1 & 2 WOULD NOT CONNECT. REMOVED & REPLACED THE CAPTAIN`S AND FIRST OFFICER`S PRIMARY TRIM SWITCHES S1-321 & S1-322 IAW AMM 27-41-01.