Q: My AC is only blowing through the defrost vent and rear defrost doesn't work.

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My AC is only blowing through the defrost vent and the temperature control doesn't do anything. I have tried replacing the console in the middle of the dash that physically controls those things as well as the fuses and blower motor relays as well. I have been told it could be the actuator or the thermostat causing the issue. I also have a smaller issue with the rear defrost, which replacing thefuses didn't fix. The light doesn't even come on when I try pressing the rear defrost button.

My car has 229000 miles.
My car has an automatic transmission.

Hi there. The blend doors on your vehicle are operated by a vacuum hose. Check the vacuum lines to the engine and see if any of them are broken, has a hole, or is disconnected. Check the vacuum hose on the blend door and see if it has came off or broke. For the rear defroster, check the switch to the defroster and make sure that it has power to it and power coming out. If there is no power to the switch, then check the fuses and see if any of them are blown. The rear defroster has a blend door that opens and closes that is electronically. If the fuse is blown, either the switch has failed or the blend door motor has failed. If you need further assistance with your vehicle, then seek out a professional, such as one from Your Mechanic, to help you with your defroster vents not blowing air.

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