I tried searching but couldn't find exact symtoms. So the other day, AC was just working fine. It's been over 100 degrees for the past 2 weeks. Yesterday, I didn't drive the car at all. Then today, the ac kicks on but no cold air. One thing I noticed is the hissing sound under the dash continues to hiss. Normally, I only hear the hissing sound in the beginning then fades away. What should I do to start troubleshooting? I just had a 60K maint. done by subaru and this happens?