A/C, Heater Blend Doors, Cold Air, Broken Recirculator Door...AAHHH!!!

[staylor423]

Last summer my A/C stopped working. The compressor never kicked in when the A/C button was pressed. I bypassed the control by hooking up a 12 volt power source to the compressor and...WOW cold air. NOT THE COMPRESSOR! I checked all fuses and any wire connections for a cause but no luck.

This winter my passenger side heat went cold on me. I suspect a blend door problem. I get the "blend door travel too large" error code from the diagnostic test. No problem, I can deal with just the heat from the driver's side.

Last week the driver side started blowing cold air. Same error code for the driver's side. Now that I had no heat, I ran the recalibration sequence and still had no heat. A day later the whole thing stopped blowing. The fan was running like a champ, but only a trickle of air was comming out of the vents. I pulled the fan housing out ( 3 screws in the passenger side up behind the glove box). Low and behold, the recirculator door was broken and covering the entire fan intake. I put a temp fix on that and now have full blown cold air.

After reading up on many sites, (thanks for all the posts ) I decided to bench test the driver's side blend door actuator to see if it or the door was broken. The servo moved fine in both directions with a 12 volt source (and when running the calibration sequence) but not when hooked up to the system. When you adjust the temp controls the freakin thing should move but it doesn't. I moved the white plastic knob that the actuator attaches to and WOW heat...only on the driver's side, but it was still heat. I reached up behind the heat unit and could feel the passenger side actuator (right against the firewall if you need to know) and it would not turn when I adjusted the passenger temp control. All this leads me to believe that the blend doors are OK, maybe the control unit is bad.

Anyone have the A/C go out and the temp controls not cause the actuators to rotate?

Do I need to replace the dash control unit?

I can hold off repairing the recirc door until the spring, but I can't take freezin my arse off all winter without heat!

[jeepheaterfix]

Hello Everyone,
As many of you know, Grand Cherokees have a notorious problem of their heaters going out between 50k and 70k miles. I have managed to fix my own jeep heater problem quite easily, and if anyone is interested in learning more about this, they can contact me at jeepheaterfix at yahoo. It's a much better alternative than taking apart the dash or paying 1200 to 2000 dollars for a mechanic/dealership to do it, and I wouldn't bet on a recall.
Best Wishes.