2009 Hyundai Sonata. AC was ice cold. Couple months ago went down to barely chill. I was going to recharge it, but now have discovered that there is chilly air coming out of the two passenger side dash vents, but on the driver’s side, the vents only emit ambient temperature air. So this indicates to me there is something else wrong, like failing vent doors inside the dash? Can anyone shed any light on this? I am hoping that I don’t need to have a shop take the whole dash apart to solve it.
There’s either a problem with the blend door or HVAC control module for the drivers side.
The blend door actuator is usually accessible from under the dash.
Thanks! That helps. Since I posted this, I read about same problem others had with other makes and models of cars and they were told the advice that this problem is symptomatic of low freon because the upper part and lower part of the AC exchanger (not sure if exchanger is the right word) service the left and right AC vents, so when the freon gets low, only one side of the AC vents get supplied. So, if that is the case, the I suppose I should first recharge the Freon and only if that does not solve it, to handle the blend door actuator. - Fewix
whoever said that doesn’t know what they’re talking about.
I and others do not consider Air Conditioners a do it yourself item . As for adding refrigerant , what if that is not the real problem ? Just be safe and let a professional solve this.
To check if the refrigerant level is low set the system to cold, fan on high, open the hood and put your hand around the 3/4" A/C line near the firewall. The line should be cold, if the line is warm there is a problem with the system, possibly low on refrigerant, that can cause half of the evaporator core to be warm and one side of the vents to be warm.