I have a 2008 Prius. It has 155k miles. Car runs great, but Im getting a check engine light. I ran the code and it comes up as “Coolant Temperature Sensor”. I replaced it, and I still have the code. Coolant level is full. Can it be the “pump” or the component that the temp sensor connects to? Thanks
What is the location of the sensor that you replaced? The problem with "running the code" (by using google) is that it does come up with "engine coolant temperature sensor", but likely not the correct one. A code that reads "P0xxx" has a standardized definition (should be the same for all cars), while "P1xxx" is defined by the manufacturer. For this generation of Prius, P1116 means that the ECM doesn't like something about the coolant temperature sensor that's located at the bottom the the coolant heat storage tank (thermos) by/under the left headlight. I would suggest getting a capable scantool (that can read prius specific data from the ECM) & see what the "water outlet" temperature sensor reads. Could be the sensor, or wiring, or a coolant flow problem (seem to remember one time getting this code for a bad 3-way valve). I have seen one where there was impact damage from a parking curb. You'll want to read up on the diagnostic procedure in the service manual before replacing parts. Posted via the PriusChat mobile app.
You'd remember changing that tank temp sensor because you've got to move the fender liner out of the way and all that nonsense so it's not like one up there mounted on the engine or any of that stuff.
There's a three way coolant control valve that has a position sensor that wears out that sounds like an old floppy disk drive when it starts to fail in the front right corner of the engine compartment of the car. It takes a while to show up as an error code. If you don't hear your coolant being pumped into the thermos when you shut off the car as often as you used to that's also another warning sign. And in general, as long as there's no air in the cooling system this isn't something that is going to prevent you from using your car... I've known people who went many years before I replaced that part for them. And they're cheap if you don't buy OEM: https://www.ebay.com/itm/394097566363