AC stopped working
 

The AC in my A4 stopped working 3weeks ago (Shame for a 4months old vehicle...) . We found that out on a hot day. Since then it has been raining a lot in the Bay Area. I was able to schedule an appointment at the dealership for today (2.5wks wait) and they reported that there is no problem, the car blows cold air and hot air. Anyone have any pointers on how to replicate the problem, other than waiting for the summer to be here? Thanks.

If the dealership said theres no problem, what makes you think theres a problem? Are you using the system correctly?

How would you know the A/C has stopped working when it's the winter? Below a certain temperature the compressor turns off so what was indicating the A/C wasn't working?

2 weekends ago it was around 70f here. It's pretty obvious the AC is not working. It was working fine 3-4weeks ago. Anyways, I will wait for another such hot day and stop by the dealership.

Dealership found the problem. There was only 0.03kg of freon left, but found no leak. They filled up to 600grams and the AC is now working. I am surprised that a 5month old car with 4.5k miles on it is low on freon... is this something common?