Engine Temperature Control Actuator -N493-, Removing And Installing
WARNING: This page is about a different car, the 2016 Audi A3 and 2015 Audi A3. However, it is still accessible from the selected car via links, so may be relevant.
Refer to OVERVIEW - COOLANT PUMP/COOLANT THERMOSTAT ; Engine Temperature Control Actuator -N493-, Removing and installing.