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Discussion Starter · #1 ·
In the last month or so, my temperature gauge is intermittently not responding and then I get a warning "ENGINE HOT A/C TURNED OFF". Fans are working overtime and loud. All other gauges are working fine, engine is NOT hot and everything else seems status quo. Then randomly, everything returns to normal. Where do I begin?
 

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I would suggest starting at the connector at the engine temp sensor, examining it and the sensor pins for corrosion and how the wires look there. Might also ohm the wires between that connector and the pcm, while flexing the wires at the connector a bit.
 

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Discussion Starter · #4 ·
So, earlier I read some advice on another forum and gave it a try. I disconnected the battery and then turned the ignition key over for 15 seconds. This did the trick and immediately I had a temperature and the warning disappeared. Would this indicate something more specific?
 

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Not sure, but it may mean that the MIL (malfunction Indicator Light) code was cancelled by the battery reboot. It is possible that the warning will reappear. And if you keep disconnecting the battery the warning will be cancelled again.
 

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Discussion Starter · #6 ·
It's more the return of the temperature on the gauge that has me confused. If there were a thermometer/connection issue, I would think that the gauge issue would persist whether the battery was disconnected or not.
 

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Is there diagnostic code to go with the engine light? I think there should be given the warning that is shown. Let me know if any codes.
 

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I may have missed something. When you disconnected the battery, did you turn the ignition key while battery was disconnected? I got the impression you waited 15 seconds than reconnected the battery and all was good. It that correct? Your note was a little confusing on this point.
 

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Discussion Starter · #10 ·
I may have missed something. When you disconnected the battery, did you turn the ignition key while battery was disconnected? I got the impression you waited 15 seconds than reconnected the battery and all was good. It that correct? Your note was a little confusing on this point.
Yes, I turned the ignition key, for 15 seconds, while the battery was disconnected per advice from another forum. Then reconnected the battery and it was immediately able to sense a temperature.
Also, no code on diagnostics.
The battery reboot was successful the one and only time that I did it. Just want to know if I can narrow down what the issue was incase this issue persists. Disconnecting the battery every time will not work as a "fix" for me! :)
 

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Discussion Starter · #11 ·
Yes, I turned the ignition key, for 15 seconds, while the battery was disconnected per advice from another forum. Then reconnected the battery and it was immediately able to sense a temperature.
Also, no code on diagnostics.
The battery reboot was successful the one and only time that I did it. Just want to know if I can narrow down what the issue was incase this issue persists. Disconnecting the battery every time will not work as a "fix" for me! :)
I see now why that was confusing. I missed the step in between where I reconnected the battery and my temp gauge came to life! I may be a woman and new to fixing my own car but I would NEVER turn the engine over for 15 seconds!!!;) Only my teenage daughter would do something like that!!
 

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well it is a puzzle, as I was not aware that turning the key with a disconnected battery would do anything. Could you let me know if the problem comes back?
 

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Discussion Starter · #13 ·
well it is a puzzle, as I was not aware that turning the key with a disconnected battery would do anything. Could you let me know if the problem comes back?
I didn't either but figured it was worth a try, as it wasn't going to hurt anything! I will let you know for sure!
 

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Have you even checked the coolant level? Why did know one say this?

It’s not 1960. Coolant temp sensor is digital. You have ran out of water and the coolant sensor is now reading steam or air inside the head.
 

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I see now why that was confusing. I missed the step in between where I reconnected the battery and my temp gauge came to life! I may be a woman and new to fixing my own car but I would NEVER turn the engine over for 15 seconds!!!;) Only my teenage daughter would do something like that!!
temp gauge is a constant hot, battery don’t care. You let it cool down, lowing the temps to a readable degree. Let’s hope she’s not home schooled.
 
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