I get heat out of the defroster. when I switch to vents all that comes out is cool air not hot. what could be the problem ?
a vacuum leak^^^^^^ and or a bad heater controll switch.. VACUUM !!!!!!!!!! VACUUM LEAK / BROKEN HOSE / LINE
Have any of you had a bad battery or replaced a battery and than had this issue with your heater? Think back now, LOL! If so this is a cheap, easy, quick fix that solved the same problem you're all describing. http://sparkys-answers.com/2011/08/hvac- actuator-recalibration-procedure.html and here is a short video to help you along. I did not have the fuse described in the video so I disconnected the battery.
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