2010 Coolant Temperature Sensor

So then more than likely the temperature sensor is acting up and lighting the dash at inopportune times or there is an air bubble still in the system once it gets around that sensor the sensor sets the light if this is what's happening usually a few days of driving works the air out I don't know how often this car sits or how much. Usually when you do this you fill up to that b mark or whatever it is it's above full then you drive around and when you get finished it should be at the full mark when you're done or a little below it and you top it up. So if it's not air and we know it's not air and that's what we're standing on then the sensor must be acting up whenever this happens I guess electronics usually don't act like this but I guess anything could be possible If I know my car is not overheating by any metric smell temperature gun etc I would probably keep driving after looking at this other p code I'm working on now it seems like wiring harnesses and things can get fubar really quick in these cars I'm dealing with a p lock code that may have this problem but it has nothing to do with this here but possibly wire damage that's affecting not being able to actuate park.

 

Do you mean the high temperature warning light comes on?

How long have you owned the car?
Has the engine ever been replaced?
Has stop leak ever been put into the engine coolant system?
Where did you buy the engine coolant pump that you installed?

 

There are two engine coolant temperature sensors, and many sensors for the (completely separate) inverter/transaxle cooling system. With Techstream or some similarly-capable scan tool, you might try to datalog those readings while you drive for a while, then see what they all were when the warning light came on.

The engine temperature sensor in the cylinder head is an "Engine and ECT" PID. The one in the EHRS return hose is a "Combination Meter" PID. The ones for the inverter/transaxle are "Hybrid Control" PIDs.