# "A/C off due to high temp" loud fan sound



## vickiecosta (Sep 12, 2019)

Hi, everyone! 

So, long story short, I'm getting this error message. The first time I came across is, I was able to drive about 10 miles before it showed up again. My husband was able to change the temp sensor and it has been working fine ever since. 

But now, a year later, we're dealing with the same problem. The car has sat for over 24 hours, and it is currently 60° outside, and it immediately pops up on our dash, and the fan kicks on. I know it might be a sensor problem, but I get this nagging feeling there's something more, since the coolant levels are topped off and have been for the past month and a half. Could there be a clog? Should we change the sensor again? Anything helps!


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## TDCruze (Sep 26, 2014)

If this immediately pops up upon cold engine start up there is a problem with the coolant temperature sensor or the wiring to that sensor. The ECU is detecting a problem with that sensor and to protect the engine in case it actually is overheating turns the cooling fan on to "high" speed. This is usually accompanied by a CEL.


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## vickiecosta (Sep 12, 2019)

TDCruze said:


> If this immediately pops up upon cold engine start up there is a problem with the coolant temperature sensor or the wiring to that sensor. The ECU is detecting a problem with that sensor and to protect the engine in case it actually is overheating turns the cooling fan on to "high" speed. This is usually accompanied by a CEL.


Thank you so much! I'll have my hubby take a look at the wiring when he gets home.


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## Blasirl (Mar 31, 2015)

Remember there are two sensors. *EDIT* at least on a 1.4T anyways.


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## Ravenkeeper (Sep 10, 2017)

vickiecosta said:


> Hi, everyone!
> 
> So, long story short, I'm getting this error message. The first time I came across is, I was able to drive about 10 miles before it showed up again. My husband was able to change the temp sensor and it has been working fine ever since.
> 
> But now, a year later, we're dealing with the same problem. The car has sat for over 24 hours, and it is currently 60° outside, and it immediately pops up on our dash, and the fan kicks on. I know it might be a sensor problem, but I get this nagging feeling there's something more, since the coolant levels are topped off and have been for the past month and a half. Could there be a clog? Should we change the sensor again? Anything helps!





TDCruze said:


> If this immediately pops up upon cold engine start up there is a problem with the coolant temperature sensor or the wiring to that sensor. The ECU is detecting a problem with that sensor and to protect the engine in case it actually is overheating turns the cooling fan on to "high" speed. This is usually accompanied by a CEL.


If it came on after the engine got to/above operating temperature, then your coolant is LOW, you will need to start looking for a leak. Mine ('14 ECO, 1.4T) did this, and the union between the Water Outlet Housing and the Reservoir Tube was cracked, had coolant all over/around it. Then the hose from the Water Outlet Housing to the Heater Block had an allergic reaction to the oil that was blowing back on it from my oil leak. NOW, I only have the oil leak to fix.


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## Allyzul (Sep 18, 2019)

its the coolant temperature sensor


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