1990 a/c issues
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Joined: Jun 2008
Posts: 51
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From: Nashua NH
1990 a/c issues
Hi ...
My dad has a 1990 coupe that has had an interesting a/c issue the last year or so. The basic issue is that the climate control button blinks and the system will only blow hot air. It doesnt sound like the compressor is kicking on. I have tried to disconnect and reconnect the battery and the a/c will work fine for a while then all of a sudden stop. We had the system pressure checked and there are no issues there either. Any thoughts?
My dad has a 1990 coupe that has had an interesting a/c issue the last year or so. The basic issue is that the climate control button blinks and the system will only blow hot air. It doesnt sound like the compressor is kicking on. I have tried to disconnect and reconnect the battery and the a/c will work fine for a while then all of a sudden stop. We had the system pressure checked and there are no issues there either. Any thoughts?
Instructor
Joined: Jan 2012
Posts: 201
Likes: 6
From: Atlanta Georgia
Hi ...
My dad has a 1990 coupe that has had an interesting a/c issue the last year or so. The basic issue is that the climate control button blinks and the system will only blow hot air. It doesnt sound like the compressor is kicking on. I have tried to disconnect and reconnect the battery and the a/c will work fine for a while then all of a sudden stop. We had the system pressure checked and there are no issues there either. Any thoughts?
My dad has a 1990 coupe that has had an interesting a/c issue the last year or so. The basic issue is that the climate control button blinks and the system will only blow hot air. It doesnt sound like the compressor is kicking on. I have tried to disconnect and reconnect the battery and the a/c will work fine for a while then all of a sudden stop. We had the system pressure checked and there are no issues there either. Any thoughts?
Melting Slicks
Joined: Sep 2008
Posts: 2,376
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From: Cherokee National Forest TN
Has the Bose radio been changed out? If so aftermarket resistors are required when connecting the new radio to the Vette harness. AC control issues will develop without the resistors. IIRC 90 thru 92 models are effected. Info in the audio section.
Drifting
Joined: Jul 2012
Posts: 1,796
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From: Nampa Idaho
Wow, thanks for the info, I'm getting a new system tomorrow and I would have never known this! Called the stereo guys and they said they have never heard of this and never had any issues, is this a 1990 specific problem or C-4's all together?
Advanced
Joined: Jun 2009
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From: Victoria Harbour
I would jump the pressure switch and see if it is the compressor. If it is new ones sell on ebay for a LOT less.
Got one for my 87 $600 at dealer, $169 on ebay for the same thing exact same thing.
Got one for my 87 $600 at dealer, $169 on ebay for the same thing exact same thing.
Safety Car
Joined: Mar 2005
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From: Fredonia WI
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[IIRC = If I Recall Correctly]
Good luck
Melting Slicks
Joined: Sep 2008
Posts: 2,376
Likes: 110
From: Cherokee National Forest TN
Had some time, link to TSB:
http://www.corvetteforum.net/c4/dave8476/index4.shtml
Aftermarket radio head installed in my 90 without resistors = AC would blow cold at engine start up, control panel had a flashing light for a minute then AC would blow hot air. 2 resistors from the Shack fixed the AC problem. Resistors cost about 2.50 for a 5 pack.
GL (good luck)
http://www.corvetteforum.net/c4/dave8476/index4.shtml
Aftermarket radio head installed in my 90 without resistors = AC would blow cold at engine start up, control panel had a flashing light for a minute then AC would blow hot air. 2 resistors from the Shack fixed the AC problem. Resistors cost about 2.50 for a 5 pack.
GL (good luck)
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Joined: Jun 2008
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From: Nashua NH
Well I pulled the code last night, it is an 09 (Low refrigerant). The weird part is it worked before one the way to lunch and didnt work after lunch. I cant imagine the refrigerant leaked out in 20 minutes. The system was also checked a few months ago and it was full
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From: Fredonia WI
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Probably not. The freon pressure is based upon a number of factors including air temperature. The pressure might have been "borderline." Have the pressure checked and remember you have to clear the code from the HVAC before the compressor will engage again.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
My guess is the system is low on freon. You have the C68 (electronic) climate control, correct? If so, you can "pull" the error code that's causing the light to blink. Press and hold both the [fan up] and [fan down] button simultaneously for 5 seconds, and then press [fan auto]. An error code should appear on the display. Error code 09 is low freon. Once the code is set, the compressor will not start again until the code is cleared.
[IIRC = If I Recall Correctly]
Good luck
[IIRC = If I Recall Correctly]
Good luck