OBD-II code · Powertrain (generic)
P012F Engine Coolant Temperature / Engine Oil Temperature Correlation
Engine coolant and oil temperature readings disagree beyond plausible limits. The engine coolant temperature sensor feeds warm-up enrichment, fan control and closed-loop entry — a stuck-cold reading keeps the engine in open loop and rich forever.
Is it safe to drive with P012F?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOne sensor drifted
Symptoms
- Check engine light on
- Cooling fan runs constantly or not at all
- Cabin heater weak or excessively hot
- Possible long warm-up time or hard cold start
Repair at a glance
- Difficulty
- Easy
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.3–2 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Ect Sensor, Oil Temp Sensor
Related codes
- P012CTurbocharger/Supercharger Inlet Pressure Sensor A Circuit Low
- P012DTurbocharger/Supercharger Inlet Pressure Sensor A Circuit High
- P012ETurbocharger/Supercharger Inlet Pressure Sensor A Circuit Intermittent/Erratic
- P0130O2 Sensor Circuit Malfunction (Bank 1, Sensor 1)
- P0131O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1)
- P0132O2 Sensor Circuit High Voltage (Bank 1, Sensor 1)
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.