Air conditioning light blinks

[masterjedi73]

Hi Everyone -

Ihave a 2000 blazer. the air conditioning works just fine sometimes, but once in a while the A/C light will just blink (3 times each time I press it) and the a/c won't work. Then a little bit later, it might come back on.

any ideas?

thanks!

[BlazerBoyLT98]

The A/C will only work when the vent setting is on the front vents, the floor, or both. If you put it on defrost or defrost and floor it will just blink and then shut off.

[Tangent]

Originally Posted by BlazerBoyLT98

The A/C will only work when the vent setting is on the front vents, the floor, or both. If you put it on defrost or defrost and floor it will just blink and then shut off.

While I'm not flat-out saying you're wrong because I don't know what might have changed between my wife's '99 and jedi's 2000, having the A/C work in the vent setting only would be downright retarded. The only settings on the A/C controls that will not work at the same time are recirc and defrost because recirc draws air in through the defrost vents. Trying to draw air in through the same vent you're trying to blow it out of is a problem they haven't quite resolved... Running the A/C while using defrost is actually the recommended way to clear your windows faster because the A/C dehumidifies the air.

[BlazerBoyLT98]

Originally Posted by Tangent

While I'm not flat-out saying you're wrong because I don't know what might have changed between my wife's '99 and jedi's 2000, having the A/C work in the vent setting only would be downright retarded. The only settings on the A/C controls that will not work at the same time are recirc and defrost because recirc draws air in through the defrost vents. Trying to draw air in through the same vent you're trying to blow it out of is a problem they haven't quite resolved... Running the A/C while using defrost is actually the recommended way to clear your windows faster because the A/C dehumidifies the air.

in my 98 blazer I can not run the A/C while the defrost is on, in my friends 2000, you can not run the A/C while the defrost is on. The defrost uses the A/C evaporator anyway to take the moisture out of the air. Before you say something is retarded check into it. I have seen other cars and other car makers allow you to run the A/C whenever you want, in the Blazer, or at least the years I have tried it on, you can not.

[Tangent]

Originally Posted by BlazerBoyLT98

in my 98 blazer I can not run the A/C while the defrost is on, in my friends 2000, you can not run the A/C while the defrost is on. The defrost uses the A/C evaporator anyway to take the moisture out of the air. Before you say something is retarded check into it. I have seen other cars and other car makers allow you to run the A/C whenever you want, in the Blazer, or at least the years I have tried it on, you can not.

Umm, you're contradicting yourself there. You say that you cannot run the A/C with the defrost on, then you say that the defrost uses the A/C evaporator to take the moisture out of the air. Before you call me retarded perhaps you would like to investigate how exactly the evaporator takes moisture out of the air. I'll help you out some: the evaporator does only one thing - it gets cold when the A/C is running. Cold air has lower capacity for carrying moisture, therefore it dehumidifies the air. Ergo the evaporator is only capable of removing moisture from the air when the A/C is running.

[BlazerBoyLT98]

First off, I did not call you a retard, I asked you to look into what you are talking about before you call something retarded. The question here is why his light blink and does not stay on. If you try to use your A/C by pushing the A/C button on any other option then vent, floor and vent, or floor, the button will blink and the A/C will not come on. Yes the defrost uses the evaporator, but when you run the defrost it does not have to blow cold air, do you use the cold setting in the middle of the winter to defrost the windsheild? I think not. Anyway, as I said, if you have the push button A/C in your blazer it will only work with the vent, floor, or floor and vent, other then that you will not get the A/C button to stay lit, I have tried it and it does not work. And once again, if youc ould read you would see I did not call you retarded, I asked you to do some research before you called something retarded.

[blazee]

Sounds to me like you guys are arguing over the same thing. In the systems that I have seen, the push button doesn't turn on the A/C...it turns on max A/C, which is recirculate. That means that Tangent is correct about it not being able to blow out and draw in from the defrost vents at the same time and BlazerBoyLT98 is correct, because it won't work when the button is pressed.

I could be mistaken, though, because I'm not familar with the operation of the systems on newer Blazers. Mine just has three knobs....no buttons.

[Tangent]

Yeah, we're probably talking past each other trying to say much the same thing... I mis-read what BlazerBoy was saying by one word. He said "before you say something is retarded" while I read "before you say something retarded". My bad.

In any case running A/C really has nothing to do with wether the air coming out it hot or cold. That's why all automotive A/C systemshave air drawn in from the outside pass through the evaporator before the heater core. That way in defrost mode you have the A/C running cooling down the evaporator. Air is drawn in from the outside, cooled by the evaporator which condenses moisture out of it, then the now dry air passes through the heater core and is heated (assuming you've done the normal thing and turned the temp control to full hot for this) and then the now hot dry air if blown out the defroster vents onto the windshield.

[BlazerBoyLT98]

Sorry I was not trying to start a war. Here is the situation in my 98 LT. I have 3 knobs, one for fan speed, one for temp and one for where the air is blowing. Below the first know on the left (the fan speed knob) I have two buttons, one is for taking in air from the outside and the other is for recirculation. Under the knob all the way on the right (the direction of the air) I have two more buttons, one is for A/C and the other is for the rear defrost. If I have the defrost, or defrost and floor set as where I want the A/C coming out of and I hit the A/C button, I get the light to flash 3 times and shut off and the A/C will not come on. if I have it set to anything but those, the A/C works fine and the button stays lit. I hope that clears up what I was trying to say and maybe that is jedi's problem.

And again I did not mean to offend anyone here

[BlazayBlazerious]

Simply put, the AC light blinking and going off when the vents are set to defrost and the AC button is pressed is just your blazer's way of saying, don't worry brutha, I got it covered...you're going to get AC and like it!

Nice battle, by the way!

[Tangent]

Originally Posted by BlazayBlazerious

Simply put, the AC light blinking and going off when the vents are set to defrost and the AC button is pressed is just your blazer's way of saying, don't worry brutha, I got it covered...you're going to get AC and like it!

Nice battle, by the way!

What he said.

[BlazerBoyLT98]

Originally Posted by Tangent

What he said.

Exactly, but you are not going to get cold air from the defrost, you will get cool air from the outside but not like when it is on the front vents.

[Tangent]

Originally Posted by BlazerBoyLT98

Exactly, but you are not going to get cold air from the defrost, you will get cool air from the outside but not like when it is on the front vents.

What does the temperature have to do with the A/C copressor running? The heater core is after the evaporator and the temperature is entirely controlled by the mix flap which is in turn controlled entirely by the temperature knob.

[BlazerBoyLT98]

I am just giving the reasing on why the light is blinking.

[Tangent]

Gotcha.

Umm, I disagree with you about something else though.

I don't know what yet, but we've been going back and forth for too long to just stop cold turkey.