This could be a problem with the blend door actuator on your vehicle. The blend door actuator is what controls if and how much Air Conditioning/Heater is to be directed to the vents. If the blend door actuator decides to fail while it is in the blend door is in heat, then that's where it will stay. So no matter how full the Freon charge is, all's you will ever get is heat. I have included a link for you to got to down below:
I have also included a diagram of the location of the HVAC exploded diagram in the diagrams down below for you as well. Please go through this guide and get back to us with what you are able to find out.
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Thursday, May 2nd, 2019 AT 11:40 PM