defaud

I own an Audi A3 2009 with a 1.4L petrol engine.Recently i was getting off from work and it was really hot outside. I started the car and it worked for a few meters and then just died. Engine was off, control pannel was off. Then it struggled to turn back on but when i shaked the shifter it would consistently turn on and work a bit before again turning off. The battery is new, it has been a week since and it seems it is due to hot weather, car is otherwise perfectly fine. When it is on it works without issues. I have read some forums here about this issue and some people suggest that the problem is in the dashboard, however when i unplug the dashboard the car still works (not sure if that is useful i know only the basics around cars so i am sorry if i say something irrelevant). I would be greatful for any suggestions and advice.