Welcome to 2CarPros. The expansion valve won't cause this issue. This is usually caused by a failed mode actuator under the dash on the drivers side. It selects the floor dash and defrost modes. To replace it you need to remove the duct extension from the HVAC box. Then you reach up and remove the screws that hold the actuator to the HVAC box. It will usually come off with the cam attached. Installing the replacement only adds the fact that you need to line the cam up with the slot and the AC cam as in the second image.
Then you need to re-calibrate. To do that you remove the HVAC fuse for 2 minutes, Reinstall the fuse and turn the key on and let the system calibrate. That should take less than a minute.
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Tuesday, September 24th, 2019 AT 5:18 PM