A/C fan won’t kick on

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GMswin13

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Ok I’m not sure how more clear I can be.
The blower motor works fine the one behind / under the glove box. The 2 coolant fans in front of the engine attached to the radiator/condenser are always on low when the engine is running….now say you wanna turn on the AC turn the blower motor on high hit the A/C button the COOLANT FANS normally turn on high periodically all vehicles do this I’m not sure why it’s confusing.
In my case when I hit the AC button everything works fine but not so cold air cause the coolant fans won’t kick on high.. I’m trying to figure out if anyone has ever had this issue… I’m not sure how else to explain this other than making a video
 

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so basically all you get when you turn on the ac is hot air?
if so then you need to have some deeper trouble troubleshooting performed by someone with a gauge and/or scanner tool to determine what exactly is happening.
it could be a sensor, could the hvac controller, etc
do either of the hvac pipes under the hood that enter the firewall feel cool/cold or warm/hot? do they look frozen? any moisture/sweat on them?
 

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And does the engine coolant temp sensor report accurately? Usually when they fail the radiator fans are on all the time but at least rule out the sensor.
 
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GMswin13

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My buddy has a really nice scanner we’re gonna take a look. I do know one of the lines were cold no condensation nothing puddles. Haven’t checked the other line.
Back in the winter the thermosdat was bad causing the coolant fans to run on high constantly so I changed that and the temp sensor and fixed the issue. So I’m gonna have to runt some codes I suppose and proper equipment to test the Freon
 

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My buddy has a really nice scanner we’re gonna take a look. I do know one of the lines were cold no condensation nothing puddles. Haven’t checked the other line.
Back in the winter the thermosdat was bad causing the coolant fans to run on high constantly so I changed that and the temp sensor and fixed the issue. So I’m gonna have to runt some codes I suppose and proper equipment to test the Freon
A scanner should be able to command the system on and show if there is any electronic problem, you might want to do a.little YouTube 101 on what the sensors should normally read. There was one guy on here who was a pretty good hvac wizz but haven't seen him post anything in a while
 

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I wouldn't trust the gauge on the can. PERIOD.

Get yourself a decent set of gauges. Verify the compressor is even turning on.

Don't get caught dumping freon in the atmosphere.
 
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GMswin13

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Well I took it to my buddies shop put his ac gauges on it it’s full and correct where it needs to be.. a code was up for radiator coolant control sensor was reading 33 degrees. I’m not sure if this particular vehicle has more than one temp control sensors cause I changed the one that’s next to the thermostat housing 3 times already but that one is called coolant temp control sensor. And the fans aren’t working properly but I can’t find anywhere that the fans have a coolant fan control module or not?
 

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I hope you're using OE GM parts -- from a reputable source -- since aftermarket parts aren't always as reliable.

If you could monitor that sensor that reads 33° (is that F or C?) with a scanner, unplug it (the one you replaced before) to see if the temp reading changes. That should be a two-pin connector so you could short the pins to see if the scanner reading changes.
 

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