There should be a button with a picture of a windscreen with lines in it...press that and the ac comes on, focusing all the air to the windscreen. For the back ones, the button should be near the gear stick on the left hand side with a similar picture. You don't need ac to do this is you have normal heating controls...I have ac because mine is a cupra. And i kinda over exaggerated on the bit about blasting the air on the back windows lol...sorry guys lol..but mine goes within a min