Got the check engine light and it indicated P0115 - "Engine Coolant Temperature Sensor Circuit". Took some pictures/notes of the process. Hope someone finds it useful!

http://www.lovehorsepower.com/SubaruDocs/CoolantTempSensor.html

 

-Joe

http://www.lovehorsepower.com//SubaruDocs/subaru_page.htm

Thank you very much for posting this. I went to Autozone and they provided this code a few months ago but I never did anything about it until it began to start hard after outside temps dropped to the 40's. I had no idea where to find the sensor until I started looking for help on here! Put a new sensor in and the service engine light is gone!

 

Thank you!

 

Chuck

Those pictures would have been immensely helpful when I changed mine two years ago. It took me a while to find the sensor and a while longer to decide what I needed to remove to get access to it.

 

I'd just add that it isn't necessary to drain the coolant when you change the sensor--you won't get much leakage through the sensor hole. Of course, if it needed doing anyway, why not do it at the same time?

Very glad you found it useful!

 

-Joe

http://videos.lovehorsepower.com

Good write up!

 

This is the safest way to do it, but I might suggest that you don't have to completely drain the cooling system. The crossover pipe which the sensor is mounted in is the highest point in the system. I've actually done 2 of these sensors now without draining anything, and I only lost about 1 cup worth of antifreeze. Draining the radiator only partially would bring the level in the system below that point, allowing you to change the sensor without spilling anything.

 

Keith