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2019 Acadia - Radiator Fan runs constantly, No AC, Power Assist Reduced, Thermostat Gauge to Cold

977 Views 25 Replies 17 Participants Last post by  Aces' dad
We have this 2019 Acadia where all of a sudden, at random, the radiator fan runs on high constantly, the AC stops blowing cold air, the thermostat gauge on the dash drops to the C, and the Power Assist is reduced and pops up as a message on the dash as well. Sounds like this may be a common problem among Acadia's. It resets at random and everything appears to be normal for a while. In addition, there are no check engine lights and no codes to check.

What is the issue so I can fix what needs to be fixed?

I don't want the dealer to tell me 8 different things and my bill to be astronomical.

Thanks for the help!
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It is a common issue with the '19. Almost certainly a failed thermostat assembly. It's a $1200-1500 job at the dealer, but should be covered by your powertrain warranty if still in effect.

There are reports that the some of the replacement parts are on nationwide backorder.
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If I purchased extended power train warranty would that cover it? Mine is also doing the same thing
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If I purchased extended power train warranty would that cover it? Mine is also doing the same thing
It may. It depends on the content covered int the extended warranty . . . . and somewhat on how it is interpreted.
Some have even gotten it replaced under the normal power train warranty. . . some not.
What year Acadia do you have and how many miles?
If I purchased extended power train warranty would that cover it? Mine is also doing the same thing
Are you talking about a warranty from one of those guys that calls you once a week at dinner time?
It may or may not cover that repair and will most certainly be a pain to deal with.

You are better off just paying the dealer for the repair.
Same happened to my 2017 SLT.. it's the thermostat... they usually be back oreded.. I got mine from Rock Auto over a year ago.. Took me a few hours to do... been good ever since
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We have this 2019 Acadia where all of a sudden, at random, the radiator fan runs on high constantly, the AC stops blowing cold air, the thermostat gauge on the dash drops to the C, and the Power Assist is reduced and pops up as a message on the dash as well. Sounds like this may be a common problem among Acadia's. It resets at random and everything appears to be normal for a while. In addition, there are no check engine lights and no codes to check. What is the issue so I can fix what needs to be fixed? I don't want the dealer to tell me 8 different things and my bill to be astronomical. Thanks for the help!
Replace Thermostat Assembly. Cost: over $1200. Sorry, I had same problem, 2019 Acadia
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We have this 2019 Acadia where all of a sudden, at random, the radiator fan runs on high constantly, the AC stops blowing cold air, the thermostat gauge on the dash drops to the C, and the Power Assist is reduced and pops up as a message on the dash as well. Sounds like this may be a common problem among Acadia's. It resets at random and everything appears to be normal for a while. In addition, there are no check engine lights and no codes to check.

What is the issue so I can fix what needs to be fixed?

I don't want the dealer to tell me 8 different things and my bill to be astronomical.

Thanks for the help!
I would do some visual look and compare between outside temperature display and engine temperature display if they are not too far off or if they way too far between the 2 gauges then it would be your ambient temperature sensor. If you have good heat at idle the thermostat is good, if your engine is not overheating then your thermostat is good, majority of people replace the thermostat for no reason.
We have this 2019 Acadia where all of a sudden, at random, the radiator fan runs on high constantly, the AC stops blowing cold air, the thermostat gauge on the dash drops to the C, and the Power Assist is reduced and pops up as a message on the dash as well. Sounds like this may be a common problem among Acadia's. It resets at random and everything appears to be normal for a while. In addition, there are no check engine lights and no codes to check.

What is the issue so I can fix what needs to be fixed?

I don't want the dealer to tell me 8 different things and my bill to be astronomical.

Thanks for the help!
I had the exact same issue and the dealer fixed it under the power train warranty. They said the issue was the thermostat. I just had this fixed last week so to early to tell if the issue will return. I will update this post at a later date. Hopefully you are still within the 60k miles and 5 years on the original sale. Good luck. FYI, my Acadia is a 2019 SLT2 with the V6.
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We have this 2019 Acadia where all of a sudden, at random, the radiator fan runs on high constantly, the AC stops blowing cold air, the thermostat gauge on the dash drops to the C, and the Power Assist is reduced and pops up as a message on the dash as well. Sounds like this may be a common problem among Acadia's. It resets at random and everything appears to be normal for a while. In addition, there are no check engine lights and no codes to check.

What is the issue so I can fix what needs to be fixed?

I don't want the dealer to tell me 8 different things and my bill to be astronomical.

Thanks for the help!
Disconnect negative battery cable for 5 minutes and reconnect this resets the ECM
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Disconnect negative battery cable for 5 minutes and reconnect this resets the ECM
The thermostat gets stuck open.$ 765.00 to replace.
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We have this 2019 Acadia where all of a sudden, at random, the radiator fan runs on high constantly, the AC stops blowing cold air, the thermostat gauge on the dash drops to the C, and the Power Assist is reduced and pops up as a message on the dash as well. Sounds like this may be a common problem among Acadia's. It resets at random and everything appears to be normal for a while. In addition, there are no check engine lights and no codes to check.

What is the issue so I can fix what needs to be fixed?

I don't want the dealer to tell me 8 different things and my bill to be astronomical.

Thanks for the help!
The thermostat sticks open sending false information to the computer. This creates all the issues. I finally had the t stat replaced for $765.00. It’s under the intake manifold.
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My 2017 2nd Generation had the same problem... Thermostat and housing assembly was replaced...problem solved.
AMT extended warranty paid for the repair, $1200. Parts were on back order during Covid19, and it took 2 weeks to get parts.
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We have this 2019 Acadia where all of a sudden, at random, the radiator fan runs on high constantly, the AC stops blowing cold air, the thermostat gauge on the dash drops to the C, and the Power Assist is reduced and pops up as a message on the dash as well. Sounds like this may be a common problem among Acadia's. It resets at random and everything appears to be normal for a while. In addition, there are no check engine lights and no codes to check. What is the issue so I can fix what needs to be fixed? I don't want the dealer to tell me 8 different things and my bill to be astronomical. Thanks for the help!
You likely have a faulty temp sensor ,usually on left side, top front of engine. Causes AC to stop, fan to blow and temp gauge irradict. Auto store OBD tester could confirm.
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I had the same problem on my 2013 Chevy Equinox, happened intermittently over last year and a half. Changed Coolant Temp Sensor twice, Thermostat once, changed coolant, changed Engine Control Module but still had the problem and had to disconnect the battery to reset the ECM. May have been a week to a month plus between the problem. What appears to have solved it for me has been replacing the Coolant Temperature Sensor Connector, I cut the wires from the old connector and used butt connectors to attach the new connector, got it from local Chevy dealer parts dept, but I see they're out there on ebay, amazon etc. Been over a month and seems to have corrected the problem. I attached a picture of a connector that looks similar. Circuit component Automotive lighting Cable Composite material Electrical wiring
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We have this 2019 Acadia where all of a sudden, at random, the radiator fan runs on high constantly, the AC stops blowing cold air, the thermostat gauge on the dash drops to the C, and the Power Assist is reduced and pops up as a message on the dash as well. Sounds like this may be a common problem among Acadia's. It resets at random and everything appears to be normal for a while. In addition, there are no check engine lights and no codes to check.

What is the issue so I can fix what needs to be fixed?

I don't want the dealer to tell me 8 different things and my bill to be astronomical.

Thanks for the help!
The dealer will cost way too much and what to change out parts until fixed 1200 to 1500 I know painfully. It needs a thermostat so take it to some body else or do it your self.
Any thoughts on the following issue... I attempted to replace the temp sensor. Part of the brass thread broke off in the block. Normally, I'd say there are probably ways to get the rest of the sensor out without too much difficulty, but space is such an issue. Any possibility of tapping a new hole at a different location for the temperature sensor? Not good.
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