A/C Compressor Issues Due to Cooling Fan?


gungfudan

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I have a 94 Mazda B3000. I had the A/C compressor main seal blow on me two weeks ago. I changed it out had my friend who owns a shop charge it up for me. A few days later I start the truck and the compressor is dragging and almost destroyed my serpentine belt. So I took it to him he said it was leaking. So he put new o-rings in and it stopped but it started acting up again the next day. Took it back and wouldn’t you know leaking in the same place on the compressor. So I go to Advance Auto get a warranty exchange and I change it out got back to my friends shop charges it up and the mechanic figures out the problem.
I installed a new water pump, thermostat, hoses, heater core, radiator, and installed an electric fan about three months ago. Well apparently the radiator fan has to be running when the A/C compressor is on because the pressure will be to high the radiator fan is not on. I did not know this.
I also think this needs to be mentioned on the tech page for the 3.0 electric fan article.

But my question is this:
Is there a way to have the Radiator fan turn on when I have the compressor on that does not have me just bypassing the thermostatic switch I installed for the radiator fan?
 


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RonD

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I would change your AC high pressure switch, it should shut off AC compressor clutch power when pressure gets too high, this prevents fittings from blowing out.


Yes, you could install a 5 pin 12v relay on the thermostat activation wire to the current fan relay

Use relay pin 30 for the Fan relay activation
Pin 87A for thermostat activation
Pin 87 for AC compressor ON, relay ON

12v Relay diagram here: http://www.gtsparkplugs.com/images/mini-automotive-relay-wiring-840x.jpg

Not sure if you use Ground or 12v to activate Fan Relay but either way this can be used
30-87A are connected when added relay is OFF, so thermostat activation
30-87 are connected when added relay is ON, AC activation

Added relay would be activated by AC clutch 12volts, relay's coil(85, 86) is only .5 amps so won't effect AC power circuit
 
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