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Old 09-01-2018, 12:49 AM   #1
putnam00
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A/c not engaging

Ok. I’m trying to install my A/C from classic auto air. I checked the compressor wire and had power. Got it all hooked up and added Freon and It wouldn’t kick the compressor on. I then checked the wire and it didn’t have power. So I checked the a/c fuse and it was ok. So what else should I check
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Old 09-01-2018, 09:34 AM   #2
Andy4639
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Thumbs up Re: A/c not engaging

On the inside the truck at the unit the micro switch that sends power to the compressor. I had to tweak mine in the 56 to make contact.
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Old 09-01-2018, 02:27 PM   #3
Stocker
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Re: A/c not engaging

Quote:
Originally Posted by Andy4639 View Post
On the inside the truck at the unit the micro switch that sends power to the compressor. I had to tweak mine in the 56 to make contact.
x2. I cleaned it thoroughly and cycled it manually at least a hundred times, finally got it to where it would "usually" work. Got a new switch, no problems now.
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Old 09-01-2018, 03:10 PM   #4
Coley
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Re: A/c not engaging

Yep....its up under the dash and if you reach way up behind the glovebox you should be able to find that little switch and activate the button on the end.
Without the a/c underdash vent linkage aligned and pushing on that button....your compressor (and clutch) won't click in and spin.

worth checking.
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Old 09-01-2018, 10:43 PM   #5
Wrenchbender Ret
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Re: A/c not engaging

You may have to use a jumper wire to engaug the compressor clutch until you get enough Freon in to build up pressure. The low pressure keeps the comp. from coming on when the pressure is low.

George
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Old 09-01-2018, 11:17 PM   #6
weq92f
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Re: A/c not engaging

Be careful jumping the compressor.

If you pulled a good vacuum on the system before releasing the refrigerant, there should be plenty of pressure to kick the compressor on.

It's probably best to go and get support from ClassicAutoAir with respect to the setup and the issues.
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