Joel4motio

Have exactly the same issue, 2017 S3.

Local (trusted) garage flushed the heater system through. Only obvious thing on VCDS(?) was that the internal thermostat in the passenger side for the clima control was reading 10c higher then the drivers side does.

Get moderate heat when fans are low speed (1 or 2) but this disappears when I turn the fans up. 
 

Radiator gets hot, inlet/outlet for matrix is fine. 
 

possibly narrowing this down to the control unit in the dash itself. What's involved in replacing this? Any coding etc? 
 

Best

On 12/31/2020 at 1:47 PM, RDeboys said:

Hi I'm having similar problems with my Audi A3 1.6 2015 heater with it blowing cold air. However both pipes to and from the matrix are hot and when I have the blower on at a very very low speed I get hot air our of the vents.  As soon as I turn up the blower speed the heat disappears and the vents blow cold.

Does anyone have any ideas or advice?

Many thanks

Manage to get anywhere with this, exact same issue.