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  #1  
Old 09-03-2008, 06:54 PM
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A/C Aux fan

Is the A/C Aux fan in front of the radiator supposed to run any time
the A/C is on and the compressor is acutated? No thermostat correct?
Mine isn't coming on, and looking at a schematic for not my year 85, but
the only I have for a 79, it looks like it should run anytime the compressor
is engaged. Is this correct? Thanks

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  #2  
Old 09-03-2008, 07:41 PM
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Acutally

I think that there is a sensor on the drier plus engine temp that will turn on the aux. fan. Someone correct me if I'm wrong.........
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  #3  
Old 09-03-2008, 07:43 PM
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The aux fan relay is actuated by a temp switch on the receiver/drier. There is no direct connection between the compressor and the fan. There are no other mechanisms that actuate the fan.

If the refrigerant level is low, the temp won't get high enough to trigger the switch. You can test the circuit (excluding the switch) by jumpering the temp switch with the key in the "run" position.
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  #4  
Old 09-03-2008, 07:44 PM
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Drier

That pressure switch on the drier also controls the compressor. My compressor is working fine. I just need to know that if the compressor
is engaged does the fan always come on?
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  #5  
Old 09-03-2008, 07:46 PM
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Quote:
Originally Posted by NoSparkNeeded View Post
That pressure switch on the drier also controls the compressor. My compressor is working fine. I just need to know that if the compressor
is engaged does the fan always come on?
The fan only come on when the temperature exceeds a specific value........such as when the vehicle is not moving and there is no airflow across the condenser.
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  #6  
Old 09-03-2008, 07:46 PM
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Is the drier a temp or pressure

Is the drier a temp or pressure switch? I thought that one was a protection against low refrig. pressure and it also stopped the compressor?
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  #7  
Old 09-03-2008, 07:48 PM
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Quote:
Originally Posted by NoSparkNeeded View Post
That pressure switch on the drier also controls the compressor.
The pressure switch only controls the compressor. It has nothing directly to do with the fan.

Quote:
Originally Posted by NoSparkNeeded View Post
I just need to know that if the compressor
is engaged does the fan always come on?
No.
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  #8  
Old 09-03-2008, 07:49 PM
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To clarify

Can the compressor be working fine, and the fan not come on for a reason
OTHER than a broken fan?
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  #9  
Old 09-03-2008, 07:49 PM
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Quote:
Originally Posted by NoSparkNeeded View Post
Is the drier a temp or pressure switch? I thought that one was a protection against low refrig. pressure and it also stopped the compressor?
There are two switches.........the temp switch controls the fan and the pressure switch allows the compressor to run.
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  #10  
Old 09-03-2008, 07:50 PM
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So there are TWO switches on the drier?

I'll put my shoes on and go take a look. Thanks guys
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  #11  
Old 09-03-2008, 07:53 PM
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Quote:
Originally Posted by NoSparkNeeded View Post
Can the compressor be working fine, and the fan not come on for a reason
OTHER than a broken fan?
1. Low refrigerant level.
2. Temp switch inop.
3. Fan relay inop.
4. Wiring/fuse.
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  #12  
Old 09-03-2008, 07:54 PM
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Yep two switches

I'm embarrased. Yes two switches I check the fan one after work tomorrow. Just needed a god place to start thanks again.
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  #13  
Old 09-03-2008, 07:57 PM
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The temp switch normally has pigtails. If you remove the wires and connect them together, the fan should run. If it does, chances are good that your refrigerant level is low.
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  #14  
Old 09-03-2008, 08:12 PM
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You guys are THE BEST!!

I couldn't wait 'till tomorrow. I went out in my jammies ( I go to work at 3AM). and
pulled the temp switch connections. Jumpered ,the fan came
right on. Cleaned off the spade connectors. Warmed the switch
a bit with a glass gun and checked with an ohm meter. Seems to work.N/O
cold ,warmed to ? 150, clicked to closed. Cleaned the connections with emery. Put it all back. Can't warm up the car now, but I KNOW it will work tomorrow. Thanks to you folks that was a Staples commercial Easy Button.
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  #15  
Old 09-04-2008, 12:37 AM
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I'm not familiar with the term "glass gun"". Enlighten please. I'm gathering it's a heat gun, but what's the glass part. Thanks.

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