my temp selector is reversed(hot is col cold is hot). what could be wrong??

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jeepguy4276

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I checked vac lines and everything seems right. Everything works great otherwise, and as it should. I turn the knob to hot and get cold air, turn it to cold and get hot. It blends the air fine other than being reversed. Do these temp selectors go bad?

Any ideas on what could be wrong? Is it possible the wires for the blend doors is wrong? What wires would control this?
 

Bushmonster73

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I just did the heater core on mine and the vac lines are the only thing that control the temp selector. The only possible idea I have, is that somehow the blend door actuator arm got flipped so that it is working in reverse. Not sure that is even possible, just a thought. Worse part is having to pull the whole dash just to get to it.
 

jeepguy4276

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I just did the heater core on mine and the vac lines are the only thing that control the temp selector. The only possible idea I have, is that somehow the blend door actuator arm got flipped so that it is working in reverse. Not sure that is even possible, just a thought. Worse part is having to pull the whole dash just to get to it.

But the blend door actuator is electric on these, not vacuum I thought? I did do the heater core so something could have gotten flipped. Any idea what vac lines go to the blend door?
 

Bushmonster73

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Ok, I was wrong on that one, the blend door actuator IS controlled all electronically. On the other hand I did end up having to change my blend door actuator seeing as I somehow did not get it set properly after I did the heater core. Low and behold with the new replacement (which you can only get from the dealer for an 03 Libby) it came with some instructions and troubleshooting tips. I'll pick up with the final install steps:
3) Install the actuator connector making sure to fully insert the connector until the latch becomes engaged.
4)Connect the battery negative cable.
5) Calibrate the actuator.
i) With ignition off, move the temperature selector knob on the HVAC control to the mid position.
ii) Turn on the ignition.
iii) Move the temp selector knob to full cold. Wait 5 seconds until the actuator finishes positioning.
iv) Move the temp selector know to full hot. Wait 5 seconds until the actuator finishes positioning.
6) Test the actuator for temperature change at different temperature selector positions.

Troubleshooting: (this may not work with the original blend door actuator but the replacement matched numbers and looked the exact same).
If the actuator does not seem to be functioning properly or the air seems to be too warm in full cold or too cool in full hot then a manual calibration can be performed.
A) With ignition off, move the temp selector knob to mid position.
B) Turn on the ignition.
C) Within 10 seconds of ignition turn on:
a) Sweep the temp selector knob to full cold, wait 0.5 seconds.
b) Sweep the temp selector knob back to full hot, wait 0.5 seconds.
c) Sweep the temp selector knob back to full cold, wait 0.5 seconds.
d) Sweep the temp selector knob back to full hot, wait 0.5 seconds.
e) Sweep the temp selector knob back to full cold.

Manual calibration can only be started within the first 10 seconds after ignition is applied. The 0.5 second pause on each end is important. If the pause is too short (<0.5s) or too long (>1.5s), then the calibration may not occur correctly.

I finally got mine to work correctly but had to do the manual calibration about 5 times.
Hope this helps.
 

jeepguy4276

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Thanks! That's helpful. The heat is working great other than being flipped and it's already damn cold here so I'm not going to meds with it until spring. Plus I'm having surgery Thursday that has a 3 month recovery so I won't be able to work on the jeep until after that.
 

dallas6099

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jeepguy4276, did you ever get this straightened out?
I recently bought an 03 Liberty and I am having this same problem.
I replaced the control switch because I was also having issues with the modes. It stayed on defrost. That has been corrected, but I still have hot from cold and cold from hot.
 

jeepguy4276

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jeepguy4276, did you ever get this straightened out?
I recently bought an 03 Liberty and I am having this same problem.
I replaced the control switch because I was also having issues with the modes. It stayed on defrost. That has been corrected, but I still have hot from cold and cold from hot.



No I actually ended up leaving it alone after getting frustrated with it. I know I need to get it done but other projects have been more important. My next check is to pull the dash again to see if the actuator or blend door got flipped somehow. But that takes pulling the dash and I haven’t had the time.

I’ve thought about switching things at the switch itself but don’t know what wires would be switched for a cheesy fix I guess. So I’ll just spend the time to figure it out one of these days. Ugh
 

Billwill

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I think Bushmonsters reply from 2014 on how to calibrate the system is very valid.

The heat control is electrical so if the calibration procedure does not help download the relevant year Jeep KJ Service Manual here.....there is a Theory Of Operation section on how the Blend Door works and section 8W has the wiring diagrams. I believe that you can get a good view of the Blend Door action by removing the Glove Box.

The control of where the air gets directed to foot well, demist etc. is vacuum controlled so if the vacuum pipe from the manifold....vacuum pump on CRD....tears or comes off then it defaults to Demister mode.

Index of /manuals/Jeep/KJ
 

CWBenjamin

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When I install a new actuator, do I do the calibration with the actuator plugged in, but not installed?

Also, should the new actuator gear line up already or do I need to open it up and rotate it to fit?
 

Robochop

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Has anyone figured this out yet? I have tried 3 different actuators and they all do the same thing. Neither of the above directions seem to be working. I have taken an HVAC unit apart at the junkyard and it seems impossible for the door to break or become reversed. It has to be something with the motor it self. I have taken it in and out several times and tried to rotate it but it still acts backwards. I'm open to other suggestions at this point. Thanks
 

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