Air conditioning light blinks


masterjedi73
06-28-2005, 08:03 PM
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
06-29-2005, 01:44 PM
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
06-29-2005, 04:28 PM
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
06-29-2005, 04:33 PM
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
06-29-2005, 04:45 PM
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
06-29-2005, 05:06 PM
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
06-29-2005, 05:40 PM
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
06-29-2005, 06:14 PM
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
06-30-2005, 09:51 AM
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
06-30-2005, 01:43 PM
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
06-30-2005, 04:05 PM
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. http://instagiber.net/smiliesdotcom/contrib/legionxs/wavey.gif

BlazerBoyLT98
06-30-2005, 08:22 PM
What he said. http://instagiber.net/smiliesdotcom/contrib/legionxs/wavey.gif

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
06-30-2005, 11:09 PM
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
07-01-2005, 04:38 PM
I am just giving the reasing on why the light is blinking.

Tangent
07-01-2005, 06:04 PM
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. :D

masterjedi73
07-02-2005, 07:53 AM
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.

But it's set the same way i left it when i turned the car off. Then when i start the car again, sometimes it won't work.

I took it to the dealership and had them look at it. Of course it was working fine when i took it in but they ran some codes on it and said that there was a short in the low pressure guage.

Then yesterday (after I had it repaired) it stopped again, for about 1 minute. So I have to take it back.

wolf pack 359
07-24-2005, 03:15 PM
I have been battling this problem for a year. Very intermittant and annoying to boot. I think it may be the beginning of a low voltage sittuation. I replaced the battery and alternator and after I charged the battery really good it seamed like it worked fine for a few days then it acted up again and the next day the truck wouldnt start. I charged the battery and took it over to check out the alt and batt and they said maybe a bad batt cable. So anyway after my blazer cools down abit I am going outside to check it out. Maybe related maybe not.

luscombe8
07-05-2007, 09:17 PM
Climate Control Blazers have two sensors. One is above your head to the right in the headliner above the drivers door. It gets mold and dirt on it. Gentle unscrew the waffle grille and blow some compressed air across it to clean it. There are two fuses, number 9 and 21, both are 20 amp, please check that you have both in good condition. Check them with the ignition OFF and re-seat them well before turning the ignition back on. I have not found the second sensor yet, but it is somewhere in the dash, dealers aren't talking. Mine blinked when the outside air was warmer than 75 and then after 3 minutes, the thing will turn on if both knobs are set to AUTO. I have better luck with mine, but it still requires some experimentation before I get cooled air. If it works when the temp knob is set (goes off and on) then I think the temp control is OK, it does go off and on (holding 70 degrees). This leads me to believe it is some sort of sensor, (touchy in warmer weather). Any other help is appreciated. Thanks

ZL1power69
07-05-2007, 10:03 PM
luscombe8, this thread is now over two years old. please refrain from posting in old threads. feel free to start a new thread in the problem diagnosis section.

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