have you verified the rear air compressor lines are connected? follow then under the hood all the way down the pass side frame rail and then thru the rear floor. if connected run the ac for 10-15 min and feel the lines under the rear to see if one is cold the other is warm or hot if not this will sya blockage in the lines if so then you got an issus with the heat / ac blend door motor. you will have to pull the whole quarter panel and get access to the syystem and clea and test the blend motor if it does not move swap it for the floor top motor and see if the issue changes. if so the motor is bad if not you might have a bad switch.......mike
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