What it means
The control module checks whether engine oil temperature sensor B gives a plausible reading under current operating conditions. It sets this code when the reading is outside the expected range or does not change as expected.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Engine oil temperature sensor B reports oil temperature to the control module, which uses the reading to assess engine operating conditions. This range/performance code sets when sensor B's reading is implausible for the engine's conditions or fails to respond as expected; it does not by itself prove the sensor has failed.
Common causes
Most likely first.
- Sensor reading drifted
- Sensor element aged beyond calibration window
- Sensor mounting loose - signal damping
Symptoms
- Check-engine light on
- Oil temperature reading may be inaccurate, fluctuate, or be unavailable
How to diagnose it
- Check the scan-tool freeze-frame and live data for oil temperature sensor B, noting whether the reading is implausible or remains fixed as the engine warms.
- Compare sensor B's reading with a cold engine's ambient temperature and, as the engine warms, with any available independent oil-temperature reading.
- Inspect sensor B's connector, mounting, and nearby wiring for looseness, damage, contamination, or signs that the sensor is not seated securely.
- With the engine safely accessible, monitor sensor B while gently moving its connector and harness to see whether the reading changes or drops out.
- Test sensor B and its wiring against the manufacturer's specification, including continuity and signal response, before replacing the sensor.
Common fixes
- Secure a loose sensor B mounting or connector.
- Clean and reconnect contaminated sensor B terminals if they are serviceable.
- Repair damaged wiring or connector terminals at sensor B.
- Replace engine oil temperature sensor B if its response is outside the manufacturer's specification.
Can I keep driving?
If the engine runs normally and there are no oil-pressure warnings, a short, gentle trip is usually reasonable, but monitor for warning lights or abnormal engine behavior. An inaccurate oil-temperature reading can hide overheating, so stop if an oil-pressure warning or signs of overheating appear.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.