gjsauser

Soooo an odd one happened last night. Was driving on a long trip had the air on auto around 73 degrees, have never had any issues with the a/c & heat before. All the sudden I noticed my cabin was fogging up, and air was not coming out of any vents. Could hear the fan running, and it sounded like airflow was restricted. At first I thought a vacuum solenoid failed, but after pulling over and dropping the panel under the glove box there was ice all over the box to the left of the cabin air filter. As near as I can tell my A/C compressor was on, and had frozen shut a baffle inside the vents. Running it on high heat and ECON remedied the situation shortly, but seeing as how it was 20 degrees outside the A/C compressor should have never been on in the first place? Any one ever see anything similar to this?

deilenberger

Year of your pig? You get better answers if you ask better questions.

gjsauser

It's an 08 Base

deilenberger

OK. As long as the AC button is lit up - the compressor is running. It's a variable output compressor, so it probably isn't doing much at 20F - but what it does do is dry the interior air to prevent fogging just like you experienced. It shouldn't ice up even under those conditions - I suspect you are perhaps a bit low on R134 - which can cause icing of the evaporator and expansion valve.

If you don't want this to happen - you can turn the compressor off with the air-conditioning button on the HVAC panel.