When the display is blinking it means that there'* a fault code in the HVAC system and can only be pulled by the dealer. Since it isn't blowing cold air and it'* blinking, I'm willing to bet that you're running low on refrigerant. When was the last time you had it recharged? Best way to tell if your car is low on refrigerant, start the car and crank the A/C and get out of the car and check and see if the compressor clutch engages at all, if it doesn't engage then the compressor could be bad or the system is low. More than likely the system is just low. I hope this helps.