As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTOPILOT DID AN UNCOMMANDED ROLL TO THE LEFT WHEN SELECTED TO CAPTAIN'S SIDE. DISENGAGED AND RE-ENGAGED AUTOPILOT AND IT HAPPENED AGAIN. CAPTAIN'S FLIGHT DIRECTOR COMMANDED MULTIPLE UNWANTED PITCH CHANGES WHILE IN LEVEL FLIGHT (AUTOPILOT WAS NOT ENGAGED). TRIED TO RE-ENGAGE AUTOPILOT LATER IN FLIGHT AND IT WOULD NOT ENGAGE. REPLACED NR 1 AHRS. SYSTEM OPS CHECKS GOOD IAW 22-10-00 AND 34-21-00.