Has anyone managed to fix this issue? 

Any updates on this i have same issue audi a3 14 plate

Hi I own A3 S 2ltr S line had heating problems blowing cold even on Hi and AC off. Changed the coolant thermostat, what pig slow refilled afterwork and checked for leaks. All good ran with tank cap off heater on max for 20 mins warm air, anything was better than before. Tested over 3 day short journeys one got warmer well pleased. Then temp gauge went to max warning to pull over tank overfilled. Cooling fans under bonnet running expansion tank showed small loss when cooled. Now have no heat in car temp gauge running norm then quickly rises turn on everything to try and cool it down. Slowing getting worse, I watched a german Utube on changing this awkward thing and he got in the car afterward and did something with a laptop. Does this mean I have to reset something by a Audi dealer, or do I have bleed points on the cooling system to get air out and heater going, possibly the cure problem I have just explained. Getting desperate now so any advice would be much appreciated.

On 5/6/2020 at 9:08 PM, TJP said:

no over heating..

everything is fine except no heat.   

Did you ever resolve this issue I’m having exactly the same problem