Apparently, the cooling system is OK , the sensor is bad ,

Keeping send wrong info to CPU  , reminding  controller  the engine is over heating .  The controller say OK, I  need do something to protect the engine  ,and command engine to shut down.

Why is it (temperature sensor is  bad)? Cause once u unplug the temperature sensor , the code 197 disappear right way ,and  the engine run  without any trouble . This clearly indicates the sensor not function properly.

 

Actually , If coolant level is OK and no  obvious leaking sign, yet engine  running die because of " over heating" code, logic conclusion is the sensor is bad , u even don't bother do any check .