A/C Light Blinking
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Instructor
Joined: May 2004
Posts: 165
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From: Austin TX
A/C Light Blinking
The titles pretty on the money. When I select any of my A/C buttons (OFF, AUTO, etc.) they blink and the air comes out hot. Is this a system malfunction, or do I just need a recharge? 
Keep the wave alive
Keep the wave alive
Race Director
Joined: Nov 2002
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From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
If you have the automatic climate control (which I'm assuming you do since the light is blinking) you need to put the system into diagnostic mode to get the codes. I did this to mine and it works.
1.)Turn the key to the on position, but don't start the car.
2.)Press both fan buttons (up and Down) at the sametime for at least 5 seconds.
3.)The LCD will show "-00"
4.)Push the "Auto Fan" and the LCD will show any fault DTC (or trouble codes).
If you get "09" you have low freon and will shut the system down.
If you get another code let me know and I will look it up for you.
Dan
1.)Turn the key to the on position, but don't start the car.
2.)Press both fan buttons (up and Down) at the sametime for at least 5 seconds.
3.)The LCD will show "-00"
4.)Push the "Auto Fan" and the LCD will show any fault DTC (or trouble codes).
If you get "09" you have low freon and will shut the system down.
If you get another code let me know and I will look it up for you.
Dan
Race Director
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From: San Diego, CA
What will it read if nothing is wrong...nothing I take it? Also do you hold the buttons UNTILL you get the -00, or will that happen when I stop pressing them?
Last edited by saniterium; Aug 29, 2005 at 06:27 PM.
Race Director
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From: San Diego, CA
Originally Posted by wzdads
Once you get the -00 use the fan buttons to cycle thru the codes.
Race Director
Joined: Nov 2002
Posts: 19,149
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From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Originally Posted by vetteusa
Yes, hold Until you see the -00. Then let go, and then press the "Auto Fan" button
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Here's a link to the HVAC Diagnostic Codes that you can print for reference.
In most cases like you are seeing, the 09 code "Low Freon Detected" will show. The system takes 2.2 lbs of R-12 and being down just over 1 lb will usually set the code. A good indication of low freon is the compressor clutch cycling every 5 seconds or so with the A/C in the Auto position.
You might consider doing a conversiont to R-134a at this point as R-12 is pretty expensive and if the system was operating before, it may need repairs anyway. Have a competent shop do the conversion for you. They can evacuate your system and they recover the R-12 so it can be re-used. Not a good idea to vent it into the atmosphere.
In most cases like you are seeing, the 09 code "Low Freon Detected" will show. The system takes 2.2 lbs of R-12 and being down just over 1 lb will usually set the code. A good indication of low freon is the compressor clutch cycling every 5 seconds or so with the A/C in the Auto position.
You might consider doing a conversiont to R-134a at this point as R-12 is pretty expensive and if the system was operating before, it may need repairs anyway. Have a competent shop do the conversion for you. They can evacuate your system and they recover the R-12 so it can be re-used. Not a good idea to vent it into the atmosphere.
