I have a Mazda 2014 GT 2.5L with fully automated dual zone climate control system. The air conditioner works on the passenger side and not on the driver side. And I know the driver-side air mix actuator is working fine. I am looking for idea on what could be the problem please.

As you can see in the attached table below (all temperature in F), I have placed 4 temperature sensors, one in each of the 4 air vents. I have set the dual zone temperature to different temperature with and without the A/C on. As you can see, when the A/C is ON and the driver side temperature is dial to low temperature, the air coming out on the left is by far not as cold as if I do the same for the right side. I have looked at the driver-side air mix actuator and I do see it moving when I change the driver side temperature dial from cold to hot. I have also looked at the passenger-side air mix actuator and I do see it moving as well. The air flow mode actuator is also working fine as I can change where the air comes out and it works fine.

From what I can see, there is only one A/C unit in the car, correct ? If so, what do you think the problem can be ?

 

I'm on my first Mazda so this is only my best guess based on a previous car. When the refrigerant level got a bit low (due to a slow leak) on my previous car (a SAAB 9-3), the 1st indication was the vent temperatures got warmer going from left to right. What causes this is that only a portion of the evaporator gets cold when the charge is low an therefore only the air going thru that side of the evaporator is chilled. I'm guessing that on your Mazda that is what is going on; only mirrored due to a different the layout of the evaporator in the air plenum.