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Q: No air through vents only defrost. Heat only in rear

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I have checked all vacuum lines and conection on climate control dials and I can not get any air flow through my vents and nothing for rear only heat.

My car has 178000 miles.
My car has an automatic transmission.

Hello.

If no air is flowing through your vents it may be possible that one of the AC components has failed. Common causes for the symptoms you describe are a faulty blend door actuator or blower motor. The blend door actuator is the component that directs the flow of the air through the vents. If the actuator fails or jams it may not be able to properly direct the system’s airflow, or may even cut it off completely. The blower motor is the component that produces the airflow for the vehicle’s AC system. If it fails no air will come from the vents at all. It may also be possible that some of the associated components, such as the fuses or relays may be having an issue. I would check those components and then go from there. If you need assistance with this, consider YourMechanic, as a certified technician can come to your home or office to diagnose the issue with your AC and help you repair it as necessary. Best of luck.

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