Trouble codes › P0115
P0115 Engine Coolant Temperature Circuit
Cooling
P0115 means the engine computer isn't getting a usable signal from the coolant temperature sensor.
The engine computer isn't getting a usable signal from the engine coolant temperature (ECT) sensor. It uses that reading for fuel, idle, the cooling fans and the temperature gauge, so it falls back on a default value.
Watch the temperature gauge (it may not be accurate now). The fans may run all the time as a precaution. Get it fixed soon, and stop if you see steam or the engine overheats.
Common causes
- A failed coolant temperature sensor
- An unplugged, damaged or corroded connector
- Damaged wiring
Symptoms
- Temperature gauge reading cold, hot or erratic
- Radiator fans running constantly
- Hard starting, rough idle or poor fuel economy
What to check first
- Check the sensor's connector and wiring.
- With a scan tool, compare the coolant temperature reading with the air temperature on a cold engine (they should be close).
- Measure the sensor's resistance against your service information's chart.
- Replace the sensor if the wiring is good.
What does P0115 mean on your vehicle?
The likely cause depends on your engine. iRepair researches your exact year, make, model and engine (service bulletins, recalls and owner reports) and tells you what to check first. Your first 3 questions are free.
Ask iRepair about P0115No scanner? Most auto parts stores read check-engine codes for free.
Related codes
General guidance for P0115 on most vehicles. Some makers use the same code a little differently; confirm in the service information for your vehicle, put safety first, and see a professional when in doubt.