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Radiator fans always on high with AC. Never shuts off.

Nemesis_Dawn

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So as I said in the title, both my radiator fans on my Commodore VXII SS are always on and on high speed when I turn on the AC. They only shut off a few seconds after I turn the AC off.

I cannot use the AC like this, because the fans will definitely burn out, and the fans loom connector gets EXTREMELY HOT when the fans are on high speed, to the point where anything near the connector gets hot to the touch as well. (I'm not sure if it is normal for the connector to get this hot with the fans on high speed either).

Both my AC compressor and engine loom are new, so there are no problems there, as this particular problem occured even before changing my compressor and engine loom.

What could be causing this? Bad compressor pressure switch? A faulty wire somewhere in the dashboard? Something else?
 

accentstencil

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This is perfectly normal and won't burn out the fans. It would be a problem if they didn't come on.
 

Nemesis_Dawn

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This is perfectly normal and won't burn out the fans. It would be a problem if they didn't come on.
The thing is I read somewhere that they're supposed to turn off if the pressure reached a certain number or the car reached a certain speed. They don't. Ever.

Even if I was driving for hours on a highway they never turn off. I'm pretty sure that's not how they should be working.
 

Aus78Formula

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If your compressor is cycling constantly, or even never, it's something else. The fans are doing what they are meant to do.
 

EYY

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Fans will be on when the a/c is on. The condenser preheats the air going through the radiator, therefore coolant temps are higher and fans will need to run anyway. They're working as they're designed to.
 

Nemesis_Dawn

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I wish you could guys feel how hot it gets and how long the fans keep running. This is definitely not normal.

One thing I tested out of spite was to disconnect the compressor pressure switch while the AC was on. Absolutely nothing happened, the AC kept working as if nothing happened.

I'll try replacing the switch in a few days and come back to you guys.
 

losh1971

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Sometimes fans will continuously run on high if the temp sensor is faulty. It's a protection mechanism. I don't know if that is the issue you are having though.
 

BlackVXGTS

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Sometimes fans will continuously run on high if the temp sensor is faulty. It's a protection mechanism. I don't know if that is the issue you are having though.

Agree. The first time I changed the spark plugs on my VX GTS, I accidentally damaged the temp sensor connector when removing/replacing the spark plug for cylinder #2. Had exactly the symptoms described.
 

Nemesis_Dawn

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Sometimes fans will continuously run on high if the temp sensor is faulty. It's a protection mechanism. I don't know if that is the issue you are having though.

Actually had a problem with the temp sensor before. Its connector and the sensor itself were so damaged that the car stalled on me while I was driving. Replaced both the loom and the sensor thankfully.

Unfortunately (or fortunately I guess) the fans run on high constantly whenever I turn on the AC only. My theory now is that I have a bad compressor pressure switch and the ECM isn't reading the pressure of the refrigerant, so as a safety mechanism it's making the fans run constantly on high whenever the AC is on. My suspicions rose especially after disconnecting its connector with nothing happening.

I'll have time to replace it in two days and I'll definitely update you guys.
 
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