I received a P0534 code and noticed the A/C no longer blows cold air. The heater still works and the car still runs fine. I would like to use a quick top off and would like to know if anyone has done this or some pointers to look out for. I have a 2012 model with 70K on it. I'm also in Europe so I can't just drive in a volt dealership. I tried the Opel ones but there is the language bar and I'm a diy kind of person.