As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AFTER TAKEOFF THE STAB OUT OF TRIM LIGHT ILLUMINATED, THE CREW CARRIED OUT AN AIR TURN BACK AND LANDED WITHOUT INCIDENT. MAINTENANCE FOUND MULTIPLE CONFLICTING FAULTS ON A AND B AUTO PILOT. THE STAB TRIM MOTOR WAS REPLACED, THE SYSTEM TESTED SERVICEABLE AND THE AIRCRAFT RETURNED TO SERVICE.