Hi all,
Car: 2006 base roadster, 6 speed manual.
Problem 1: The Climate Control unit keeps blowing warm air out.
Problem 2: The fan switch is not working properly (I'm assuming it's a bad potentiometer). When I turn the dial it seems to work at some speeds not at others. Also if I shake the **** it while it's on say position 4, the fan speed will studder.
What I've done so far: After reading some of the threads on here, I have changed the blower motor resistor with a unit from Amazon. I've rebuilt the Duo-Valve. Changed the cabin filter. I've also done the flushing procedure. (Let the car run on high temp for 30 minutes with windows shut).
It is still blowing warm air with the temperature controls set at neutral. If I go full A/C it blows semi cold air.

Any help would be appreciated. Thank you.

 

I have the same issue. I just recently saw a post involving Svengoolie and rebuilt duo-valve. He took the rebuild of the duo-valve to a whole new level compared to my rebuild job. Wait a sec, you are the famous Svengoolie! LOL! Nicely done there. I have three theories as to why there is "hot air". 1) There is a hot/cold deck mixer and a possible vacuum leak causing the door to flip to the hot side. 2) The climate control system is farked and just turns on the duo-valve flooding the cabin with unneeded hot air. 3) Almost like the theory 2, but the coils in the duo-valve are failing.

Does the duo-valve fail open? If it fails close, then just unplug the duo-valve.

 

Thanks about the rebuild post! LOL
I'll try unplugging it and see if there's any change. I'm also going to check for voltage. I might just bite the bullet and get a new one.

 

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Just an FYI, the duo-valves failsafe open (no power to them at all). Reason being if it is really cold you'll need the heat. Now for the fun part John. When the car is first started (hoses are cold) set the dials full range cold. Then take an analog voltmeter (with an old type scale meter movement), set for the (if memory serves me) 15 volt scale, and check for pulses from the control head at each solenoid while dials are set for cold and fan is on (leave the A/C button OFF so the compressor doesn't run). When calling for cool those duo-valve coils pulse faster closing the flow in the heater coils (test each side without touching them together). If your only by yourself, set the voltmeter up first and then start the car with dials full cool (your only checking the duo-valve pulses). You should get the highest pulse (farthest swing of meter movement) with the 2 dials full cold. IF you get no pulses with dials at full cool while the fan is ON, your not getting power to them and the coolant is circulating through the heater coils. Good luck! .


.

 

OK, if we don't get voltage pulses, does this mean replacement of the AC and Heat Control Unit?

 

I would first clamp off the duo-valve intake with a hose clamp. Thus preventing the flow of water through the valves, turn the A/C unit to full cold A/C and see what temp you get in the car. That should tell you if the A/C is working correctly and giving good cold air. If you do have cold air then the problem probably is the duo-valves. If the air isn't totally cold the A/C system needs refrigerant.

The control unit in the dash has an electrical contact connection on the rear which is a know source of problems. It can be repaired; use the search box. [ see "Index of Crossfire problems and repairs" in the in the TSB and How to Articles, look at the A/C section and then the PDF Heater-AC Fan Speed Control Removal and repair]

 

I have had two cars brought to me that blew warm (actually HOT) air no matter what. The first was a sluggish duovalve, the owner simply replaced it and did not want to "mess with cleaning a bad one".

The second was super easy - I had no power to the center pin on the duovalve. SOMEWHERE, this wire went open and the valve had no power - when it has no power, it defaults to full open which means full coolant flow to both sides of the heater core. Tearing into the harness to find the 'open' was going to take a long time, so I cut the wire near the valve, and ran a new wire from the center pin of the duovalve to the driver's side fuse box and tapped the output of fuse 15. Problem solved in 20 minutes.

Your problem 1:
REMEMBER:
Center pin must be 12 volts at all times, including when key is off.
Each outer pin feeds 1/2 the valve, one half is driver side vents, one half is passenger side vents.
Outer two pins must be at near zero volts to engage the valves and cut off coolant flow to provide for cold air
Outer two pins will be near 12 volts for warm air.
The outer pins get pulses that vary in width, the wider the time they are at zero, the cooler the air will be - but your digital meter will probably smooth these pulses and give you an average voltage reading, such that a voltage near zero = cool air and a voltage nearer to 12 volts = warm air.

The pulses come from the climate control module. If you have 12 volts on all three pins, the issue is in the climate control. If you have zero on all three pins, you have no power to the valve from fuse 15.

Problem 2:
The potentiometer in your climate control is bad - common issue. YOu can mail me the module and for $60 I will fix it and mail it back to you. DO NOT pull the module from the car until you and I talk, there are a few cautions we must discuss, or you will hate yourself when you try to put it back.

 

Thank you all for your advice!
I believe I have an analog meter and I will take the readings as suggested.
@pizzaguy I appreciate your offer and I will send you a pm.

 

I replied to your PM.

And one last time:
A personal check is fine, just toss it into the box with the module.
DO NOT turn the ***** on the module after you remove it from the car! You will hate yourself if you do, I will return it without moving the *****. Moving the selector **** after removal will cause mis-alignment when putting it back in. (Moving the fan **** is not a big deal.)

 

I've replied to your PM and will send the unit out as soon as I can.
By the way pizzaguy, you nailed it! I tested for voltage and there was none. Fuse #15 was blown. After replacing the fuse I was able to see the correct voltage.
Then I tested for the pulses as George and you had mentioned and I was able to see them going from 0 to varying low voltages and down to 0 on both outer pins.
When I can get the car outside so I can drive it I will check if everything is working well. I will also have the refrigerant level checked as Zip suggested.
Thank you all for your help!

 

Check fuse # 15 in the engine fuse box. Mine looked good, but when I checked it, it was no good.
I replaced it and now I have voltage. See post # 7 above.

 

@M60A3Driver wrote an excellent post on removing the climate control module..
https://www.crossfireforum.org/forum...tml#post996771

After examining his post and some of the above answers, I have some more qualification questions:
1) Does the fan speed dial change any of the position of the white mechanical linkages at the back of the unit.
2) The two slider ***** for passenger and driver temperatures, must have a potentiometer. Do they go bad causing the temperature to fluctuate?

I can see how the potentiometer in the fan **** can go bad and cause erratic fan speed changes.

Personally I believe the white linkages go to a vacuum valve(s?) to control the various dampers for moving air to different positions. See red arrow.

 

1. Fan speed dial does not move the two shafts. 2. Have no idea if the temp ***** have ever been a problem going bad. Finally, the two shafts key into matching socket shafts coming out of the plenum of the heat/ac box, the inside of the plenum has ductwork vanes that direct air according to the dial icons in the Heat/AC head. Good luck!


.

 

I just went through this, but I also had a compressor clutch failure. Your blend door could be sticking. There are so many posts on this site where people claim the AC blows cold on one side and hot on the other or changes from cold to really hot and cold again. Just about everything on these cars is run off of vacuum and that includes the blend door. Vacuum is typically pulled off the intake manifold just like in your old carbureted Chevy PCV or Power Brakes. Remove the battery and the battery support that holds the battery. You will find a grey tube similar to what is used in windshield washer systems. This tube will be exiting from the firewall and runs under the battery. Follow this grey tube from the firewall checking for damage that could cause a leak. When you reach the back of the intake, the tube slips into a thin rubber hose that connects to the back of the manifold. This rubber hose deteriorates resulting in a loss of vacuum. I have fixed three other Crossfires just by replacing this hose. If that isn't it, remove the glove box and panel under the passenger dash. Once you get the panel out of the way, you will see a small connector with 2-3 green hoses connecting to it. Two of the hoses will run up to the "Blend Door Actuator". If the actuator is bad, you would have heard a "clicking" noise under the dash when adjusting from cool to hot and vice-versa. If you did not hear clicking, then most likely the cause is the connector I spoke of earlier with the two green tubes exiting from it. You can buy the connector and the actuator on eBay for $40. Let us know if this helps.

 

As for fan speed and control. There are a set of sixteen horizontal pins and two alignment pins that connect the climate controls with the control circuit board. This board controls everything from the blower fan to the electric fan on the radiator (in order to maintain enough air across the condenser). These 16 pins fit very loosely into the back of the controls board. In the library section, someone drafted a pdf explaining how he fixed the problem of his blower controls randomly failing. The controls aren't hard to remove just follow the many instruction pages in the library or the YouTube. Also, you don't need special radio removal tools to get the radio out. Separate a cheap set of thin (as in width) tweezers and slide one half in each slot. Feel around until you get the tweezer under the tab(s) holding the radio. Reach out to me if you have problems. How to reach me? I don't know because I've never personal messaged anyone from here before.

 

I appreciate your replies, this is what I've done so far.
I've read all of the posts that you have mentioned. I have checked the vacuum line under the battery, when I replaced the battery. I didn't have any clicking noises under the dash.
I did have a bad fuse, #15 that was not allowing voltage to get to the duo valve. This made it revert to blowing warm air.
I have removed the climate control unit and I have sent it off to be rebuilt by pizzaguy.
Thank you,
John

 

Good, I hope everything works out.
Cheers!