First check if the air recirculation mode is turned on. If its set to fresh air, the fresh air will come out of the vents even with AC off and it can be warm if the outside air is warm, if heating mode is selected, or if the blend door actuator is malfunctioning.
The blend door in the HVAC (Heating, Ventilation, and Air Conditioning) system controls the flow of air and temperature. If the blend door is malfunctioning or stuck in the hot position, it may result in hot air being directed into the cabin. This could be due to a faulty actuator or blend door motor.
