P0197 is a generic OBD-II powertrain fault code that means Engine Oil Temperature Sensor Low Input. The ECM/PCM has detected a lower-than-expected electrical signal from the engine oil temperature sensor circuit.
P0197 may be encountered on applicable vehicles from Jeep, Nissan, Chevrolet, and Subaru. The exact sensor location, wiring configuration, reference voltage, resistance characteristics, and diagnostic strategy can vary by engine and model year.
Fault Code Description
P0197 = Engine Oil Temperature Sensor Low Input.
Code type: Generic OBD-II Powertrain Code.
Likely fault location: Engine oil temperature sensor, sensor signal circuit, wiring, electrical connector, sensor ground/reference circuit, or occasionally the ECM/PCM.
The word Low refers to the electrical input signal detected by the ECM/PCM. It does not automatically mean that the engine oil itself is too cold.
What Does P0197 Mean?
The engine oil temperature sensor monitors the temperature of the engine oil and provides the ECM/PCM with an electrical signal corresponding to the measured temperature.
When the control module detects a signal below the expected electrical range, it can store P0197. A short to ground, faulty sensor, damaged wiring, incorrect reference circuit, or electrical connector problem can produce this condition.
Engine Oil Temperature Sensor Location
The exact location varies by engine. Depending on the vehicle, the sensor may be installed in or near the oil pan, engine block, oil filter housing, or another part of the engine oil circuit.
Do not use a generic sensor location or pinout when diagnosing a specific Jeep, Nissan, Chevrolet, or Subaru. Always verify the exact component location using the vehicle-specific service information.
Symptoms of P0197
- Check Engine Light.
- Incorrect engine oil temperature data.
- Changes in engine-management strategy.
- Reduced fuel economy.
- Reduced engine performance in some applications.
- Unusual warm-up or temperature behavior.
- Additional temperature-related diagnostic codes.
- Cooling or engine-control strategy changes on some vehicles.
Common Causes of P0197
- Faulty engine oil temperature sensor.
- Short to ground in the sensor signal circuit.
- Damaged sensor wiring.
- Corroded or loose electrical connector.
- Damaged sensor terminals.
- Incorrect reference voltage.
- Poor electrical connection.
- Internal sensor failure.
- Oil contamination or abnormal engine operating conditions.
- Rarely, an ECM/PCM fault.
How to Fix P0197
1. Scan the Vehicle
Use a professional scan tool to confirm P0197 and check for additional engine-temperature, oil-temperature, or electrical codes.
2. Check Freeze-Frame Data
Review engine temperature, oil temperature, intake-air temperature, engine RPM and vehicle operating conditions recorded when P0197 was stored.
3. Check OBD Live Data
Monitor the engine oil temperature sensor PID with the engine cold and while the engine warms up.
An extremely low or implausible temperature reading compared with other engine-temperature sensors can indicate an electrical or sensor problem.
4. Inspect the Sensor and Connector
Inspect the engine oil temperature sensor, connector and terminals for corrosion, oil contamination, loose terminals, damaged insulation or physical damage.
5. Check the Signal Circuit
Using the manufacturer's wiring diagram, test the sensor signal circuit for a short to ground, open circuit, excessive resistance or incorrect voltage.
Do not assume that the wiring configuration is the same between Jeep, Nissan, Chevrolet and Subaru.
6. Test the Sensor
Compare the sensor's resistance or signal output with the manufacturer's specifications. If the circuit is correct but the sensor remains outside specification, the sensor may require replacement.
7. Verify the Repair
After the repair, clear the code and monitor the oil-temperature data during a complete warm-up cycle. Confirm that the reading changes plausibly and that P0197 does not return.
P0197 Diagnostic Signal Flow
P0197 OBD Live Data
OBD live data can help distinguish an actual temperature condition from an electrical signal problem. Compare the oil-temperature PID with coolant temperature, intake-air temperature and ambient temperature.
If the oil-temperature value suddenly becomes extremely low, remains fixed, or is clearly inconsistent with the engine's actual operating condition, inspect the sensor and circuit before replacing components.
P0197 Jeep
On applicable Jeep vehicles, P0197 indicates a low input from the engine oil temperature sensor circuit.
Check the sensor, connector, wiring and signal circuit. A short to ground or sensor failure should be considered when the oil-temperature PID is implausibly low.
P0197 Nissan
On applicable Nissan vehicles, P0197 indicates a low engine oil temperature sensor input.
Diagnosis should include the sensor circuit, connector, wiring and live-data reading. Nissan-specific service information should be used for the exact sensor location and electrical specifications.
P0197 Chevrolet
On applicable Chevrolet vehicles, P0197 indicates that the ECM has detected a low input from the engine oil temperature sensor circuit.
Inspect the sensor and wiring and compare the oil-temperature data with other available temperature readings. The exact diagnostic procedure depends on the engine and model year.
P0197 Subaru
On applicable Subaru vehicles, P0197 indicates a low input from the engine oil temperature sensor circuit.
Check the sensor signal, connector, wiring and related electrical circuits. Use Subaru-specific wiring diagrams and specifications before testing or replacing the sensor.
P0197 vs P0196
P0196 indicates an engine oil temperature sensor range/performance problem, while P0197 specifically indicates a low input from the sensor circuit.
P0197 vs P0198
P0197 indicates a low input from the engine oil temperature sensor circuit, while P0198 indicates a high input.
Is P0197 Serious?
P0197 should be diagnosed rather than ignored. The code may be caused by a relatively simple sensor or wiring fault, but the underlying problem should be confirmed before continued operation.
If the vehicle also has an overheating warning, low oil-pressure warning, severe engine noise or major loss of power, stop driving and investigate the underlying problem.
Can I Drive With P0197?
Limited driving may be possible if the engine is operating normally and there are no overheating or lubrication warnings. However, the fault should be diagnosed as soon as possible.
P0197 Repair Cost
- Electrical diagnosis: approximately $50–$150+.
- Wiring or connector repair: approximately $50–$250+.
- Engine oil temperature sensor: approximately $80–$300+.
- ECM/PCM diagnosis or repair: potentially considerably more.
These are general estimates only. Actual costs depend on the vehicle, engine, parts prices and labor rate.
Common Repair Mistakes
- Replacing the sensor without testing the signal circuit.
- Ignoring a possible short to ground.
- Using the wrong wiring diagram or sensor pinout.
- Failing to compare oil-temperature live data with other temperature sensors.
- Assuming that “low input” means the engine oil itself is cold.
Related Codes
- P0195 – Engine Oil Temperature Sensor Circuit
- P0196 – Engine Oil Temperature Sensor Range/Performance
- P0198 – Engine Oil Temperature Sensor High Input
- P0199 – Engine Oil Temperature Sensor Intermittent
FAQ About P0197
What does P0197 mean?
P0197 means Engine Oil Temperature Sensor Low Input. The ECM/PCM has detected an electrical signal from the sensor circuit that is lower than expected.
How do I fix P0197?
Check the freeze-frame and live data, inspect the sensor and connector, test the signal circuit for a short to ground or other wiring fault, and test the sensor according to manufacturer specifications.
What is the most common cause of P0197?
Possible causes include a faulty engine oil temperature sensor, shorted signal wiring, damaged connectors or other electrical circuit problems.
Does P0197 mean the engine oil is too cold?
No. P0197 describes a low electrical input signal from the sensor circuit. It does not automatically mean that the actual engine oil temperature is too low.
Can a short to ground cause P0197?
Yes. A short to ground in the sensor signal circuit can pull the signal voltage lower than expected and may trigger P0197.
What does P0197 mean on Jeep?
On applicable Jeep vehicles, P0197 indicates a low input from the engine oil temperature sensor circuit. Check the sensor, wiring, connector and signal circuit.
What does P0197 mean on Nissan?
On applicable Nissan vehicles, P0197 indicates a low engine oil temperature sensor input. The exact sensor location and diagnostic procedure depend on the engine.
What does P0197 mean on Chevrolet?
On applicable Chevrolet vehicles, P0197 indicates a low input from the engine oil temperature sensor circuit. Inspect the sensor and circuit before replacing components.
What does P0197 mean on Subaru?
On applicable Subaru vehicles, P0197 indicates a low engine oil temperature sensor input. Verify the wiring, connector, sensor signal and manufacturer specifications.
Is P0197 the same on every vehicle?
The base definition is generic, but the sensor design, location, wiring, monitoring conditions and diagnostic specifications can differ between Jeep, Nissan, Chevrolet, Subaru and other manufacturers.
Final Result
P0197 is a generic OBD-II powertrain code meaning Engine Oil Temperature Sensor Low Input. The ECM/PCM has detected a lower-than-expected electrical signal from the engine oil temperature sensor circuit.
The correct diagnosis is to check live data, inspect the sensor and connector, test the signal circuit and look for a short to ground or other wiring fault before replacing the sensor.
For applicable Jeep, Nissan, Chevrolet and Subaru vehicles, the exact sensor configuration and diagnostic procedure can differ by engine and model year. Always use the manufacturer-specific service information for the final test.