I do not get cold air from the right side vents on my 2012 XK. I get normal airflow but at ambient temperature - no cooling. The left side gets nice cold air and works as expected.

My initial thought was the temperature blend stepper motor was not working. But I do get heat if I set the temperature up so it is at least partially working.

Before I start tearing the dash apart, had anyone else had a similar problem or any recommendations?

thanks,
Dave Christensen

 

I may be over-simplifying here, but is your Dual Zone climate on?

 

I am not sure that it can be turned off. No matter what I set the temperature for the right side it will not blow cold air. I can make it blow hot air by setting the temperature up high, but not cold. So I don't think the right side climate control is off.

I can sync the right and left temperature controls and the right still blows ambient temperature air while the left blows cold. Something is preventing the air from flowing over the evaporator on the right side.

 

Ok, just checking the obvious. I miss obvious stuff myself sometimes.
My wife's old LS did something like this, but with the heat. The heater line mixing solenoids were bad there, so nothing like you have.
Wish I could help.

 

Mine is doing the same thing. Checked codes and 'low system pressure' came up... Maybe with reduced cooling capacity the drivers side get cooling priority.

 

Remind me how to synch the a/c please

 

It's under the climate screen on the center display.

 

OK- I need to find my manifold gauge set and look at the pressures. I assumed that since the left side was cooling OK that the R134a charge was OK.

thanks

 

I hope that low refrigerant is the only problem - looks like the instrument panel needs to be removed to secure access to the motor that controls air temp on the passenger side.

One way is to set the temp control on the driver's side to either the coldest setting; or the hottest setting. That will force the passenger's side temp to the same setting.

 

Thanks for everyone's help. The freon charge was low - about 35 to 40 psi on the suction side @ 100F ambient (I live in Tucson). Charged it up and both sides are blowing cool.

I don't understand why one side is affected and the other is not. I am not going to worry about that now. Hopefully it stays working so I can stay cool when it gets hot this summer!

 

Hi Dave,

What is the low side pressure reading, now that you've added some R-134a?

 

At 100F ambient, 55psi. It took one 12 oz can to get there.

 

That's an odd one to be sure.

 

I looked in the repair manual and could not find a spec for low-side/high-side pressures, and was wondering how you decided that 55 psi. is good.

Also, does your vehicle have a sight glass on the high-side, and if so did you notice the amount of bubbling in the glass prior to and subsequent to your adding refrigerant? Thanks!

 

If you look at typical AC charts they say at 100* F the low side pressure should be between 50-55 psi.
AC Pressure Chart | R-134a Temperature Pressure Chart

 

Internet search for the pressure. No sight glass.

From reading the service manual over I think they want the service guys to evacuate the system and then refill by weight, 1lb-8oz of R-134a. They assume that if it is low it is leaking and something should have been replaced to fix the leak which would require opening the system.

 

I agree with the assumption that there is a leak. I suspect depending on how much of a leak the OP will need an AC service where leak detector and visual inspection will find the problem. We use an electronic sniffer which to me is a cleaner way then using a UV dye .

 

I have a cheap electronic sniffer and could not find a leak with it. The car is about seven years old now. If it does not need a recharge for another seven years I will be happy. If it leaks down quickly I will find the leak and fix it.

 

That's kind of where I'm at on mine. I have no idea what it's AC history is but the PO said they hadn't driven it for 18 months before I bought it so I'm thinking charge and see.