Coolant Temperature Sensor?

INSPECTOR58

MEMBER
2017 BUICK LA CROSSE
3.6L
60,000 MILES

When my temperature gauge stays on "C" then the A/C will not work, and the fans will run for exactly 5 minutes when the engine is turned off. Sometimes the gauge works normally (heats up) the A/C works, and the fans don't overrun (normal operation). Sometimes while driving the gauge suddenly drops to "C". Sometimes while driving with the gauge at C, the gauge will suddenly jump to normal temperature.

I suspect the coolant temperature sensor or its circuit. Does this sound plausible? Where is the sensor located on this motor?

Bob

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
42,895 POSTS

Yep, the sensor is the first stop on this kind of problem. Here is the location of the sensor so you can change it out. It looks like it is a little under the intake manifold. I would run the codes to see what comes up as well. You can get a CAN scanner (Controller Area Network) which will work on most cars from Amazon.

Here is a video to show you how:

https://youtu.be/u-4syLc-ifQ

and

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

Here is one for about $99.00 if you need it:

https://amzn.to/3ZixY4v

Check out the images (below). Please let us know what you find.

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