The AC blower works, but the air that comes out is not cold.
Often times the air not being cold is due to low refrigerant levels. Once the refrigerant gets low, the pressure falls. The pressure sensors in an effort to protect the A/C system wont let it come on. The fan will blow but the compressor is not actually engaged. A mechanic will usually need to refill the refrigerant system and add UV dye or use an electronic leak detector to determine where the leak is. Working with pressurized refrigerant can be dangerous and sometimes requires a license, so getting professional assistance from a mechanic such as one from YourMechanic to help you is advised.
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