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I have the issue of AC on the passenger side and warm air on the driver side. I reviewed the post on here saying that the actuator door sometimes sticks or needs replaced all together. Yesterday I pulled the actuator door motor off (driver side) and with the wire still attached I turned the car on and the motor worked properly. With the car still running and the AC still on I rotated the white-ish colored rod that the actuator motor attaches to. When I did this it went from semi cool air to extreme hot and back. I put everything back together and watched to make sure the actuator door was working properly. The passenger side remained ice cold during this test so I know that ac is on and working. The question that I have is that even after confirming that the AC is working and the Actuator door is not jammed why am I still only getting warm air on the driverside but the pass side is ice cold? Is there something I am missing. I know the mode actuator is working correctly as well.

The semi cool air feels just like when you set your thermostat on 60 degrees with ac off. But ice cold on passenger side. Does the AC split in to 2 systems once it comes in the dash?

Thanks ahead of time
BTW 2000 Booneville SSEi


Brandon

Pick youself up a AC re-charge from your local autoparts store. Your system needs a top up. That will fix you right up.

I did try that about a year or 2 ago, I have been dealing with this for about 4 years now. l will do it tomorrow and let you know how it goes. I'll try anything at this point.

Well I got home today after buying the ac charge system. When I connected it the gauge said 45psi already and was in the normal zone. I went ahead and hit it anyway it went up to 100psi the gauge was now in the red area. So I stopped, it only took a second to get up that high. Still same problem. Cold on pass. side warm air on the driver side. Is there a chance the refrigerant needs replaced or can it lose cooling properties? Should I vacuum out the old refrigerant and replace with new? I am getting cold air on the pass side so I know the AC system is working correctly. I have a feeling its with in the dash still, I will try any suggestions.


TY

Brandon

Silly question, but did you have the car running and the AC on high? 100 psi seems high. If you did then I would suggest getting the system re-charged. So yes, vacuum out the old and replace.

I did have the car on and ac was on high. I recently just bought a vacuum pump and a set of ac gauges so I will try that tomorrow afternoon. Thank you for your help so far. I will post what the outcome is tomorrow night.

Refridgerant doesn't lose it's cooling capability, when they evacuate your system at a shop they just run it through a filter and re-use it. All it has to do is gain and lose heat, it doesn't physically carry anything.

bc21 wrote:The semi cool air feels just like when you set your thermostat on 60 degrees with ac off. But ice cold on passenger side. Does the AC split in to 2 systems once it comes in the dash?

Hi Brandon,

Yes it does on the automatic climate control system. Per the manual, the automatic system ( CJ2 ) has an air mix door for the driver's side and a separate air mix door for the passenger side. The manual system ( C67 ) has only a single air mix door for the entire system.

Based on your description, I'm guessing the driver's air mix door is sticking so that it always allows air flowing through the heater core to mix with the air flowing through the AC evaporator. End result being the driver side never gets cold..you only have cool to hot air available. It's not a problem with the A/C system per se..it's just that the chilled air is getting reheated by the heater core on the driver's side of the car.

If you look at the HVAC box from under the instrument panel on the driver's side, do you see two door actuators motors? If so, the one closest to the bottom is the driver's side air mix door. The other one is the mode selector for the whole system (selects defrost, ac, heater, etc.) On the passenger side you always have two, one being the passenger side air mix and the other being the outside air control.

If you can confirm the mode and mix doors on the driver's side are working, the problem may be in the temp sensor on the driver's side or the electrical controls. (In other words, the air mix doors are working correctly, they are just getting told the driver's side is colder than it actually is so the system is intentionally mixing hot air from the heater on that side.)

Great i am glad you told me about the refrigerant. I had a feeling that it is in the dash and not the ac system. So I got home from work and it is 2 late to get under the dash so I will start 1st thing in the morning. So it sounds like what your saying I can swap out the temperature sensor from my other car (fyi: same type of car 2000 ssei) and see if it is the solution.



I will update in the morning.

Thank you.

That would be as good of a plan is any. At least you could eliminate a possible cause of the problem and focus on other parts of the control system.

The discharge temp sensors plug into the HVAC ductwork on either side of the instrument panel. Based on the line drawings in the manual, they are very close to the foot well courtesy lamps (the light bulbs under the dash that light up the floor of the car when you open the doors.) Swapping then left to right or with one from another car would tell you if the problem follows the sensor. The pinouts and connector shells on the temp sensors are identical, so they are probably interchangable.

The diagnostic charts repeatedly say to cover the sun load sensor in the top of the dash when doing diagnostics. Probably not a bad idea to do while checking sensors if the system is using that to figure out which side of the car is getting more sunlight and altering the air mix accordingly. It is located in the center of the defrost grill, top side of the dash. It is pair of photo-cells.

Worst case you can take it to a dealer and have them plug into the system with a scan tool where they can see the sensor readings and signals the control head is sending to the mix door motors.

If you have a multi-meter, you can measure the resistance of the inside temp sensors while they are disconnected. The range is 1.5k ohm (hot - 104 degrees F) up to 16.9k ohm (cold - 14 degrees F) on a linear scale. (pretty simple sensor, resistance changes with the inverse of temp.)

Ok a little late on reply. I swapped the air temp sensor from my other car no luck. I swapped the hvac control module in the dash that controls everything still no luck. My next step is to try swapping the photo eye in the defroster grill. If not I will start taking the dash board apart untill I find why cold air is not entering and the duct work on the driver side.

Thanks

Watching this post because this is the same exact problem I am having as well on my 2000 SLE.. Cold on pass side.. But luke warm too hot when adjusting from 60 all the way to 90 on driver side but never cold.. Learning a bunch from this web site though .. thank all of you guys for your input and time..


Jeff

i have seen many times on different vehicles that have dual zone climate control a low or incorrect refrigerent charge cause the same exact problems your experiencing. unfortunately the gauge on a recharge can sucks. get yourself a manifold gauge set and find out what the pressures actually are. however, if your blowing cold on one side its saft to say your pressures are within spec. i know you mentioned that you pulled the actuator out and it moved? i would also reach up and try to manually twist the door and see if it moves freely or binds up. also make sure where the actuator attached to the door that there is no breakage. ive seen it and its only plastic.

Since my last update I decided to pull the dash apart and get down to the hvac unit and find out if something was jammed inside. I am going to attach some pics. i did not find and problems with it physically. Such as blockages or broken door. i have done the procedure of removing the actuator and operating the door by hand [by rotating the shaft back and forth from hot to luke warm and back again nothing changed still warm. With the dash apart I did find a second ambient temp sensor on each side located near the access panel on the dash when you open the door. I will be swapping this with the other side. I swapped the lower sensor under the dash but that did not change anything, and rightfully so I would not think that the lower sensor would be providing any feedback to the hvac unit for the a/c. I will swap tomorrow and update.

I will add pics when I figure out how to add them

Mind boggeling.. Im gonna try to find some gauges and top it off right and see if that fixes it.. after reading several others doing this cured it.. .. but yeah I would think if it is blowing cold on one side it should be cold on both .. I didnt pull the accutator motor.. I just simply reached up and could feel it moving when turning the drivers side temp knob from 60 to 90..

Can you post your results and pics- since I have exactly the same problem. Thanks

I keep trying to post pics but can't figure out how to do it. I tried pressing the Img icon and nothing happens, can't cut and paste, or drag and drop. Just trying to add pics for this post.

Try this:

viewtopic.php?f=9&t=146

I just bought my Bonneville 4/15/10. It's a beauty. I swear that I tested the a/c when I test drove it and it worked. However, I am now experiencing the same problem that you described... ICE Cold air on passenger side. Warm (sometimes cool NOT COLD) air on Driver's side. Dual Climate Control
I'm a girl and I don't have a lot of money to mess with this but I swear it's been the hottest Spring/Summer EVER! Can you give me some ideas of where to start?!

A friend of a friend said that he would have to take apart the whole dash board to check to see if the air/mix door actuators are functioning. Is this correct?

I'm also having trouble with an intermittent no start / no crank.
I got stranded one night about an hour away from home, went back the next day to have the car towed to my mechanic and when I got there it started right up! I took it to my mechanic anyway and he kept it for a week. He couldn't get it to fail so per a GM service bulletin he decided it was probably the Ignition Switch and he replaced that...$160 later, that wasn't the problem. I initially thought it had something to do with rain or moisture but I really can't connect it to anything. It randomly happens. Aside from the time I described where I was stranded, it has always started on the 2nd or 3rd try and sometimes even if I just keep it turned all the way to the right when it doesn't start right up. There's just a few second delay. Just wondering if anyone has any ideas or has experienced the same thing?