1980 heat and ac dont work.. Please help
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Instructor
Joined: Aug 2011
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1980 heat and ac dont work.. Please help
Ok.. I just got this car two weeks ago.. so far.. i have repaired the non opening headlight doors.. great info up here... a non working horn... again great info from the site.. turned out to be the button was not making contact..
Now my biggest delima.. the seller said something about a fuse but I cannot remember... There is no response at all when I move the speed lever or any switches on the ac unit controls. The compressor does not run nor does the fan blow...
When do I start.. I saw a post about the vacuum control unit but where is that located.. I have never done AC before so I need very specific guidance to get the system working again..
Any help is much appreciated..
Also as I saw in another post.. there is no hissing in the cabin when I move the switches..
Now my biggest delima.. the seller said something about a fuse but I cannot remember... There is no response at all when I move the speed lever or any switches on the ac unit controls. The compressor does not run nor does the fan blow...
When do I start.. I saw a post about the vacuum control unit but where is that located.. I have never done AC before so I need very specific guidance to get the system working again..
Any help is much appreciated..
Also as I saw in another post.. there is no hissing in the cabin when I move the switches..
Pro
Joined: Sep 2011
Posts: 613
Likes: 11
From: EVANSVILLE Wisconsin
Just fixed the same issue with my 80'. There's a relay under the hood that went bad, It's on the right side near the hood spring. It was a quick fix and the system works great now. Of course there are other things that could have gone wrong like a bad motor switch, but the relay is more likely the issue.
Here's the part I ordered: http://www.ecklerscorvette.com/corve...1980-1982.html
Hope this helps!
Here's the part I ordered: http://www.ecklerscorvette.com/corve...1980-1982.html
Hope this helps!
Thread Starter
Instructor
Joined: Aug 2011
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I just found the 25amp fuse and repalced it... the fan runs fine on the defrost.. heat and vent.. as soon as I move the control to the ac side it blows the fuse.. I disconnected the ac compressor to see if the short was there when engaging.. it blows regardless if its connected or not... does this still sound like the relay on the firewall?
Thread Starter
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ok.. I checked the ac leads.. they had been spliced but not touching.. I removed the tape and they had electrical connectors on them.. then I noticed the solinoid lead was not connected... I hooked it up and the fuse did not blow.. the compressor did not run but I am assuming its not charged.... am I getting closer to a fix?
Race Director
Joined: Apr 1999
Posts: 11,520
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From: CORVETTE 77 385 C.I. TEXAS
The lead may have been grounding since fuse did not blow so sounds like you got it.
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
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Thread Starter
Instructor
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when I turned the key.. the solenoid on the carb bumped but the clutch on the Ac compressor did not engage... is it the switch or low... can I bypass the switch without damage to my electrical (over ride it) to see if the clutch is forced to engage?
Last edited by driddick; Sep 5, 2011 at 01:01 PM.
Race Director
Joined: Apr 1999
Posts: 11,520
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From: CORVETTE 77 385 C.I. TEXAS
Yes you can jump the switch & hear it click on w/o running....
Race Director
Joined: Apr 1999
Posts: 11,520
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From: CORVETTE 77 385 C.I. TEXAS
You can check further by briefly inserting something into one of the valves to get an idea of pressure & keep eyes away from valve!
You can call around for R-12.
Note for R134, I would use a smaller orifice tube like the Ford (2 O-Rings) Red .062 in place of the GM White .072.
You can call around for R-12.
Note for R134, I would use a smaller orifice tube like the Ford (2 O-Rings) Red .062 in place of the GM White .072.
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Instructor
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Thank you so much for all your help... This forum is great and the members are very knowledgeable... I was able to diagnose every issue this car had that previous owner did not address..
Now if I can figure out how to remove the console cover / gauge cluster I can install new bulbs.
Now if I can figure out how to remove the console cover / gauge cluster I can install new bulbs.
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
They would not need to take it completely apart- they might flush it.
You did good on this yourself.
The thing you need to know about removing the gauge cluster is it attaches to the console underneath in front so remove both console sides.
You did good on this yourself.
The thing you need to know about removing the gauge cluster is it attaches to the console underneath in front so remove both console sides.
Thread Starter
Instructor
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Hey.. YOU really helped.... you have Corvette repair to a science..
Thank you very much for your help and quick responses.. I was running outside and back to the computer diagnosing... It was very cool havign the fast responses waiting... THANK YOU AGAIN SOOOO MUCH
Thank you very much for your help and quick responses.. I was running outside and back to the computer diagnosing... It was very cool havign the fast responses waiting... THANK YOU AGAIN SOOOO MUCH
