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AC Always On?

Fitty

By Fitty
in Ask A GM Technician

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Fitty New Member

Fitty

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I've got an '01 Silverado, standard cab, Z-71. The heat and AC seem to work fine EXCEPT, the AC seems to never really shut off. If I turn it off it still blows in chilled air (no, it's not the chilled duct-work -- it stays cold for as long as I'm driving). I can over-ride it with heat, but that's not the way it's supposed to be (is it?).

 

Fitty :banghead:

GM-Tech Senior Enthusiast

GM-Tech

Posted
Posted

No, the A/C does not stay on when you turn it off. It does come on automatically when you put it in defrost though.

 

If you turn it off, go out and look at the compressor clutch and see if it's turning. I'm not talking about the pulley that the belt is on, because that's always turning. Look at the plate on the front of that pulley. If it's stationary, the compressor is not on.

Fitty New Member

Fitty

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No, the A/C does not stay on when you turn it off.  It does come on automatically when you put it in defrost though.

 

If you turn it off, go out and look at the compressor clutch and see if it's turning.  I'm not talking about the pulley that the belt is on, because that's always turning.  Look at the plate on the front of that pulley.  If it's stationary, the compressor is not on.

 

 

 

 

 

Then why does it continue to blow chilled air for as long as I drive it? If I stop, restart later, it still blows chilled air. I know the difference between chilled ait and outside air. :banghead:

GM-Tech Senior Enthusiast

GM-Tech

Posted
Posted
Then why does it continue to blow chilled air for as long as I drive it? 

 

I have no idea. You're there and I'm not. I'm not debating what you're saying. I can only tell you that the a/c is not SUPPOSED to be on all the time. I'm not saying yours isn't. If you don't even want to take the first step to find out what's going on, I can't help you.

Fitty New Member

Fitty

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Hey GM-Tech, why are you being so touchy? I just asked a question. Why do you assume I hadn't already checked the compressor clutch?. Trust me, I know HOW an AC system works. What I don't know is why the AC is always working even when the AC switch and indicator light is "off". Bad switch? Wiring problem? Never happened before to a Chevy truck? I just wanted some advice before I take it to the dealership. Sorry.

 

Fitty :confused:

 

Then why does it continue to blow chilled air for as long as I drive it? 

 

"If you don't even want to take the first step to find out what's going on, I can't help you."

 

 

 

 

GM-Tech Senior Enthusiast

GM-Tech

Posted
Posted
Why do you assume I hadn't already checked the compressor clutch?.  Trust me, I know HOW an AC system works.

 

I guess I'm touchy because you postings, including this one, come across with a somewhat snotty attitude. How the heck am I supposed to know what you checked and what your level of expertise is? Some people that ask questions here can barely change their own oil.

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