Another heater blend door issue

[Jleal]

2010 Liberty Sport. I went to use the heater the other day and only got cold air. I jumped on this forum and found a library of no heat posts, read a handful and decided to check out the blend door actuator. I quickly confirmed that the heat blend door actuator want moving when heat was adjusted. So I peeled the tape back on the wiring harness and was able to swap the plug for the vent for actuator with that for the heat blend actuator. After doing so I adjusted both knobs and while under the control of the vent knob, the heat blend door actuator works. Under heat knob control the vent selector actually doesn't work. This leads me to believe that the heat control knob is bad. It's there any way to test the hvac controls? Does anybody have a pinout for the controller? Any help/advice is appreciated.
Thanks

 

[WestlakeOH]

There are two blend doors in the unit, one directly connected to the blend door actuator and the other is linked to the first blend door. I have an 03 liberty that was blowing cold air a few years back and I started by replacing the actuator, then cutting a hole in the front of the A/C by the front blend door and neither fixed anything. The real problem was linking bar from the main blend door to the other blend door that makes it rotate with the main door had broke and the only way to repair was pull the dash completely off, open the HVAC unit and either repair the link bar or replace it and the blend door altogether. I ended up at Pull-A-Part salvage yard and pulled a whole HVAC unit out of another wrecked unit as I wasn't sure what was wrong with mine until I opened it up. It's a PIA either way. the only good news is the liberty dash is not that hard to remove because it is so shallow.

 

[Jleal]

I ended up ordering a replacement climate control off of ebay. It came today and I tried it out. After I plugged it in and tried to adjust the heat, it opened the blend door to full heat but then wouldn't adjust back. I unplugged the unit and plugged in my original unit to see if I could get it off of full heat. It adjusted back to full cool and now it is working properly allowing me to adjust the temp, weird.

 

[Craig R]

I ended up ordering a replacement climate control off of ebay. It came today and I tried it out. After I plugged it in and tried to adjust the heat, it opened the blend door to full heat but then wouldn't adjust back. I unplugged the unit and plugged in my original unit to see if I could get it off of full heat. It adjusted back to full cool and now it is working properly allowing me to adjust the temp, weird.

My '02 was stuck on hot, not cold like most posts here. I just finished replacing the actuator. Still stuck on hot. So I started experimenting. And here is what it does. Start Jeep with selector set to cold - blows cold air. Turn selector to hot - blows hot air, but stays on hot. Start car with selector on cold, then turn selector to the right 5 clicks past the 12:00 position and it will still blend back to cold. Turn it 6 - 9 clicks to the right past 12:00 and it stays hot....will not blend back to cold. To get it to cold again, turn the car off, set to cold, then restart. Even pulled a used temperature selector at a junk yard. Results same for original and replacement selector. Still troubleshooting.

 

[ltd02]

Almost sounds like the door itself is sticking. Cold is the default so maybe somehow when the Jeep is shut off it is sufficient to move it from its sticking point. Have you tried to do all this with the fan on full blast? Maybe it'll clear something out?

 

[Craig R]

Almost sounds like the door itself is sticking. Cold is the default so maybe somehow when the Jeep is shut off it is sufficient to move it from its sticking point. Have you tried to do all this with the fan on full blast? Maybe it'll clear something out?

Thanks for the reply. I've tried it in all four fan settings. Setting it to cold, shutting the engine off and either turning ignition to ON or starting the Jeep is the only way to get it back to cold. Until I find another explanation, I put a little piece of white electrical tape at click 5 and told my wife how to reset it to cold if she needs full blast heat, which is pretty much all the time for the described "Freezy Weasy".

Your instructions on disassembly were excellent! Gave me what I needed to start the job. Re-assembly only went long because of the troubleshooting I did before sealing it all back up. Plus I cleaned all the console and dash components before putting it back together. The car hasn't looked this good in years.