so as the title states, when it gets 25 degrees or colder out, my air conditioning doesn't seem to want to work. When I push the button for air conditioning to defrost the windows in the blazer, the light just flashes for a few seconds then turns off. I looked up the issue in the manual and it said that when light flashes, "this function is not available at the time" Just wondering why this is doing this and is it normal? BTW the ac works normally when its ~25 or warmer out. any helps appreciated.

 

Functional Check
Complete the following steps in order to determine if the system is functioning correctly:
[ol]Cycle the ignition switch from the ON position to the OFF position and then back to the ON position. Verify that the following actions occur: [align=left]



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The heater A/C temperature LED lights. [/align][align=left]



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The mode LED lights. [/align][align=left]



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Both of the LEDs repeat at the same positions while the ignition is cycled. [/align]Turn on the ignition. Leave the ignition on for at least three minutes in order to allow the blower delay to time out.
Important:The compressor does not operate at ambient temperatures below 3°C (38°F).

Inspect the mode sequences in order to verify that the mode sequences are operating correctly:
[ol]Set the temperature to the 16°C (60°F) setting. Verify that the following results occur: [align=left]



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Cold air flows from the instrument panel. [/align][align=left]



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The blower motor runs at a high speed. [/align][align=left]



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The noises level changes when the air is in recirculation. [/align][align=left]



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Hold a small piece of paper against the inside air temperature sensor holes. If the sensor hose is aspirating correctly, the paper will remain against the sensor holes. If the sensor hose is not aspirating correctly, the paper will fall to the floor. [/align]Set the temperature to the 32°C (90°F) setting. Verify that the following results occur: [align=left]



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Warm air flows from the heater outlet. [/align][align=left]



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The blower motor runs at high speed. [/align]Set the temperature to the 32° (90°F) setting. Select the DEFROST setting. Verify that the following results occur: [align=left]



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Warm air flows from the defroster outlets. [/align][align=left]



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The blower motor runs at high speed. [/align]Important:Ensure that the vehicle is in a garage at room temperature.
If the vehicle is hot or cold, the system will run at a high blower motor speed at 24°C (75°F) and BI-LEVEL.

Set the temperature to the METRIC 24°C (75°F) setting. Select the BI-LEVEL setting. Verify that the following results occur: [align=left]



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Air flows from the instrument panel outlets and the heater outlets. [/align][align=left]



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The blower motor speed slows down. If the blower motor speed remains at high speed, the blower motor may be faulty. [/align][/ol][/ol]
You may have a faulty mode door actuator.

If this doesn't help, then you'll have to have the A/C codes read on a scanner.

 

The compressor will not engage when the ambient temp is below 35 degrees F. This is a normal operating charecteristic of your blazer's HVAC system.

 

well that makes no sense! why would they not want the a/c on when its cold out? It defrosts the windows faster and with a car load of people in your blazer when its cold out isn't fun when the windows completely fog up! and in my old '95 cavalier, the a/c would stay on no matter what when you put the defrost on.

 

you could be low on Freon?

 

All cars AC will not work when the temp is under 35 degrees as mentioned above.

 

The A/C pump still cycles on and off when defrost is selected...