What was found
BOS INFLIGHT T586/13JAN AT FLIGHT LEVEL 320, AIRCRAFT YAWED HARD TO THE LEFT. EMERGENCY DOOR MESSAGE ON FORWARD EICAS. MULTIPLE DOOR LIGHTS ON OVERHEAD PANEL. LEFT YAW DAMPER EICAS MESSAGE ILLUMINATED AND REMAINED ON. TURNED OFF LEFT YAW DAMPER. DURING DESCENT MORE DOOR AND ELECTRONIC COMPARTMENT LIGHTS CAME ON. AUTOBRAKES DISCONNECTED ON APPROACH. AFTER INITIAL YAW AIRCRAFT FLEW NORMALLY. LANDED BOS WITHOUT INCIDENT. REPLACED PROXIMITY SENSOR ELECTRONIC UNIT. REPLACED RIGHT YAW DAMPER ACTUATOR AND D347 CONNECTOR. SYSTEM GROUND CHECKED NORMAL OPERATION.