Keep getting "coolant below temp" code?

2002 KIA SPORTAGE
146,000 MILES • 4 CYL • 2WD • AUTOMATIC
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JWFITZ69
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I've changed both coolant temperature sensors. Cleared code, and I'm still getting it again. Checked voltage at the connectors of the temperature sensors and one is reading 12v and the other is reading 5v. I've checked the wiring I can see, and it looks fine. I'm stumped.
Jun 24, 2023 at 1:38 AM
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STRAILER
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This happens when the engine cooling system thermostat goes out and is stuck open.

Here is a generic guide to help you step by step with instructions in the diagrams below to show you how on your car:

https://www.2carpros.com/articles/replace-thermostat

Clear the codes once completed, check out the images (below). Please let us know what happens.
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Jun 24, 2023 at 12:30 PM
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JWFITZ69
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The cooling system thermostat is a new one, as well as the coolant pump. I was experiencing the same codes even before the thermostat and coolant pump were replaced.
Jun 26, 2023 at 12:28 AM
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STRAILER
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It sounds like the PCM is going bad, what is the code exactly so we can be sure.

This guide can help:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please go over this guide and get back to us.
Jun 26, 2023 at 12:15 PM