So I've had the car for around 8-9 months and never had a problem with it. CEL came on the other day even though the car is still driving fine. Ran the scanner and PO115 came up, which looks to be the coolant temperature sensor. Now should I start by replacing the sensor, or are there certain tests I can do to pinpoint the problem? I'm just curious if anyone else with experience with this code can give me some advice. Like I said there is no change or symptoms that I am aware of. Car is operating as it should.

 

Code is open/short in sensor or wiring or bad ECU.

Can your scanner readout the coolant temp? If so what temp does it show? Read the temp engine cold then disconnect the sensor from the wiring and check temp again.

If -40F there is a open circuit sensor connected and +284F when sensor disconnected confirm good electrical contact at sensor. If OK then bad sensor.

 

So I was looking closer at the ect sensor and noticed one of the wires looks a little corroded. Could this cause the p0115 code to pop up? I tried to wiggle the wire with the engine running to see if there was a change in performance but no change. I took a video to try and get a better view and noticed little sparks coming from the corroded portion of the wire as well. I'll add a picture below.

 

Bad wiring and plug connection can cause issues. The commuter checks for an open or shorted circuit and if so set the code.