Engine Oil Temperature Sensor Malfunction
What does P0195 mean?
The P0195 code means the vehicle's onboard diagnostic system has detected: Engine Oil Temperature Sensor Malfunction. This is a moderate severity code.
Common Symptoms
- Check Engine Light on
- Oil temperature gauge reads incorrectly (if equipped)
- Transmission may shift differently (uses oil temp for shift strategy)
- Engine cooling fan may not operate correctly
- Possible reduced fuel economy
Probable Causes (Ranked by Likelihood)
- Failed engine oil temperature sensor Very High
- Wiring issue in the sensor circuit High
- Corroded or damaged sensor connector Moderate
- Low engine oil level affecting sensor reading Moderate
- PCM internal fault Low
Step-by-Step Diagnostic Procedure
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Read engine oil temperature on a scan tool with the engine cold. It should match ambient temperature (within 10 degrees F). A reading of -40 degrees F or 300+ degrees F indicates a circuit fault.
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Start the engine and monitor oil temperature. It should rise gradually and reach 200-230 degrees F during normal driving.
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Disconnect the sensor and measure resistance (similar to a coolant temp sensor: 2,000-3,000 ohms at 68 degrees F).
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Check the 5V reference and ground at the sensor connector with the sensor disconnected.
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Inspect wiring and connector for damage, corrosion, or oil contamination.
Frequently Asked Questions
Can I drive with code P0195?
You can drive short distances. The main concern is that other systems may use oil temperature data for their operation. Some transmissions adjust shift patterns based on oil temperature, and cooling fans may not operate correctly.
What does the oil temperature sensor do?
The oil temperature sensor measures engine oil temperature. The PCM uses this information to optimize fuel delivery, adjust oil pressure, control cooling fans, and on some vehicles, determine transmission shift strategy.
Is the oil temperature sensor the same as the oil pressure sensor?
No, they are different sensors. The oil temperature sensor measures heat, while the oil pressure sensor measures the pressure of oil in the lubrication system. They are typically located in different positions on the engine.