This could be because the temperature gauge has gone out but I have heard of people doing a hard system reboot to fix it, you can try a hard reboot which is done by removing the negative side of the battery, with the cable loose from the negative side of the battery, hold it to the positive terminal for 1 minute this will discharge the memory capacitors in the BCM and PCM allowing the system to reboot. This this doesn't work you need to install a rebuilt cluster. here is a video of the job being done on a similar vehicle:
Check out the images (below). Please let us know what happens.
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Tuesday, May 2nd, 2023 AT 5:00 PM