ac compressor trying to engage when heater is on?
#11
03-15-2010, 01:18 PM
My Blazer does the same thing when I have the climate control set to top and bottom. If I just leave it on the top or the bottom vents, it stops. My AC works fine otherwise.
#12
03-16-2010, 08:26 AM
Defrost setting... to defrost. Frost is frozen moisture. It is designed to run the A/C to remove moisture from the air, and dry the glass. Your truck is completely normal if the compressor runs with the defrost on. Generally, the compressor will not run if you are set to heat settings, not defrost.
#13
03-16-2010, 12:39 PM
Yes, I'm aware of the concept of "defrost" but thanks for the tutorial. However, it's not set on defrost. It's set on a normal setting of the top vents actives as well as the bottom vents.
I don't know if mine is different than yours, but I have the following options:
MAX AC > AC > Top & Bottom > Only Top > Only Bottom > Defrost & Bottom > Defrost
My compressor runs in ALL settings except for Only Top or Only Bottom. None of my other vehicles do this, and that's why I decided to mention it to the OP.
I don't know if mine is different than yours, but I have the following options:
MAX AC > AC > Top & Bottom > Only Top > Only Bottom > Defrost & Bottom > Defrost
My compressor runs in ALL settings except for Only Top or Only Bottom. None of my other vehicles do this, and that's why I decided to mention it to the OP.
#14
03-16-2010, 01:45 PM
Yep, if it's running when the control is set to 'Only Top' or 'Only Bottom' as you show above, then something is wrong. Those are fresh air and heater, respectively.
#15
03-17-2010, 10:07 AM
Sorry bro... misunderstood ya. The compressor should only run in the defrost mode, or any A/C mode, not vents or heat, as you know. If it does, there may be a problem with the dash controls. Must not be telling it to turn off. Maybe a vacuum issue... hear any hissing coming from the dash? You have visually verified that the clutch is turning on in all setting except just top, or just bottom?
#16
03-17-2010, 12:57 PM
Sorry bro... misunderstood ya. The compressor should only run in the defrost mode, or any A/C mode, not vents or heat, as you know. If it does, there may be a problem with the dash controls. Must not be telling it to turn off. Maybe a vacuum issue... hear any hissing coming from the dash? You have visually verified that the clutch is turning on in all setting except just top, or just bottom?
Sorry to hijack the OP's post, but yes, the clutch is definitely engaging. It cycles pretty quickly though. Not like in the AC/Defrost modes. I thought this was normal though (though I haven't seen it on other cars) because on my climate control there's a line that connects the Max AC, AC, and Top & Bottom settings. Here's a pic of what mine looks like with what I mean highlighted in red. I thought this behavior is what the OP was referring to.
#18
12-23-2021, 01:46 PM
Hi guys, after letting the car seat for about a week I turned it on and opened the hood and I noticed that I would hear a click and then the ac compressor would engage for about 3 seconds and then disengage, it would continue to do this until you turned the heater off(I did not have the ac on). Once the blower inside the car was off it would not try to engage.
I decided to try and see if the ac worked and it did not (the light on the button kept flashing and the compressor would engage and disengage every 3 seconds). Any idea to what this could be? the ac worked fine last year. Thanks for the help in advance.
I decided to try and see if the ac worked and it did not (the light on the button kept flashing and the compressor would engage and disengage every 3 seconds). Any idea to what this could be? the ac worked fine last year. Thanks for the help in advance.
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