Causes and Fixes P0118 Code: Engine Coolant Temperature Sensor 1 Circuit High

How to fix a P0118 Code: Engine Coolant Temperature Sensor 1 Circuit High
The engine Coolant Temperature Sensor (ECT) reports the temperature of the engine to the computer.
The (ECT) is a Thermistor that changes resistance with the temperature.
Possible Causes of a P0118 Engine Code:
Engine Coolant Temp Sensor
Wiring Problem (Open/Short)
Overheating Cooling System Issues
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[@m60user]

On a 2018 GMC Acadia, I had the Steering Assist is Reduced code, so I replaced the thermostat and ECT Sensor. That code is gone, but now I have this P0118 code. I'm hoping it is the wiring harness, which I will replace next.

[@terrykale5610]

I don't have any power to my coolant temp sensor