I had my battery replaced in my 2008 Pontiac Grand Prix and my engine temp gauge quit working. When you start the car it still goes through the normal gauge check but then just sets at cold mark.
Which engine/ the coolant temp sensor not only provides your pcm(engine computer) with info but also to your instrument cluster via the bcm or inst cluster module. Check the cts harness connector at the sensor first.
Engine's a 3.8 series 3. Kinda scratching my head on this one because everything worked fine until the battery was changed.
Check to see if the sensor wire is connected to the sensor, it may have been knocked off during the installation of the battery.
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