2016 Express 2500. Rear AC and heat are not really blowing. if you put your hand right on the vent you can feel a little bit of cool but it doesn't really change the temperature in the back cabin and it is definitely not blowing.

 

All speeds?

 

Yep, The AC and heat in the front work great, ac is cool and it blows pretty hard. Back not so much. Nothing I change on the controls seems to change it. (I can make the the vent feel a little warm or cold but can't make it blow harder or less, no difference between feet or head).

 

what's the voltage at the motor?