My A/C has been acting erratically. The compressor is good and the coolant has been checked but when I first start the engine the air blows cool/to 70 degrees (I’m in Arizona and we are still experiencing high temps of 105), but doesn’t behave if I drop the interior temp to 69. For the most part the cool air continues, even though if I manually turn the fan down a notch or 2 it will adjust itself back up...so be it, at least the air is cool. I leave the settings on recirculated air and off automatic. Suddenly hot air is blowing out of the vents and sometimes I can tap on the control buttons and get cool air back, sometimes not. We’ve already replaced the HVAC Heater Control Water Valve but it didn’t make any difference. Now I’m told I might need to replace the thermostat control valve panel, so found a couple of options on eBay for less than $100 but apparently need to remove the current one to find the serial number to made sure I order the correct one. This appears to be a major/expensive endeavor (labor wise), as it seems the entire dash might need to be removed.


This is the part I am referring to as the thermostat control panel.

Is this a ‘99-02 model? I’ve had that panel out on my ‘02. It was no big deal. The curved trim piece at the bottom pops out for access to the fasteners.

Before you commit to a new panel, please read my HVAC troubleshooting guide linked in the post above. Please test the operation of the DCCV first. No assuming it’s good just because it’s new.

After that, drive the selected temperature down until LO is displayed. This bypasses many of the automatic features. If the AC now behaves itself in manual mode, please work through the relevant section of the guide. Hopefully we can save you some money and aggravation.