P0195: The engine computer found a fault in the engine oil temperature sensor circuit.
Engine oil temperature sensor circuit fault
Severity: Severity not verified — if the car runs badly, have it inspected
The sources describe the code and its causes but do not say how urgent it is. The usual symptoms are a check engine light and some loss of fuel economy, so have it read and checked rather than ignored.
P0195 in short
P0195 means the engine computer found a fault in the engine oil temperature sensor circuit. TroubleCodes.net lists broken or corroded wiring, poor connections, blown fuses or relays, and a faulty thermostat among the causes, with the computer rarely at fault. Check the oil level and connector first.
The oil temperature sensor tells the computer how hot the engine oil is. P0195 is set when that circuit does not behave as the computer expects.
The code points at the circuit, not necessarily the sensor. Wiring, connectors and fuses are checked before the sensor is replaced.
Most likely causes
These are general causes for this code across vehicles. None is specific to one make or model.
Cause 1: Wiring, connector or fuse fault in the sensor circuit
Common general cause- Why it ranks here
- TroubleCodes.net lists broken or corroded wiring, poor connections and blown fuses or relays first for this circuit code.
- What would change this
- Rises if the connector is corroded or the reading jumps when the harness is moved. Falls if wiring and connectors test normal.
Cause 2: Failed temperature sensor
Common general cause- Why it ranks here
- TroubleCodes.net lists the sensor itself as a possible cause, though less common than the wiring.
- What would change this
- Rises if the circuit tests good and the sensor resistance is outside the manual figures. Falls if the resistance is correct.
Cause 3: Engine computer fault (rare)
Possible — needs testing- Why it ranks here
- TroubleCodes.net lists the computer as a rare cause, often after water or collision damage.
- What would change this
- Rises only after wiring and sensor test good. Falls if either is faulty.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Read all stored codes and freeze-frame data, and check the oil level.
IfOther codes are stored with it
It meansSort out the other codes first, since a shared wiring or power fault can set several.
IfP0195 is the only code
It meansMove on to the connector and wiring checks.
Step 2: Inspect the oil temperature sensor connector and wiring for damage, bent pins or corrosion.
IfA damaged, corroded or loose connection is found, or the reading jumps when the harness moves
It meansThe wiring or connector is the likely cause.
Points to: Wiring, connector or fuse fault in the sensor circuit
IfWiring and connectors look and test normal
It meansTest the sensor and its reference voltage next.
Step 3: Check the sensor circuit voltage with the key on and the continuity back to the computer with the key off.
Warning:Keep clear of hot exhaust and moving belts, and turn the ignition off before checking continuity.
IfVoltage, resistance or continuity is outside the repair manual figures
It meansThe wiring or the sensor is at fault, so repair the wiring or replace the sensor.
Points to: Wiring, connector or fuse fault in the sensor circuit
IfEverything tests normal
It meansThe fault may be intermittent or in the computer, so have a shop retest.
Symptoms
- Check engine light on
- Oil temperature reading that does not change, if your car displays it
How to fix
Step 1: Check the oil level and look over the sensor connector for damage or corrosion with the engine off and cool.
Step 2: Ask a dealer or shop to check the circuit before buying a sensor for P0195.
On your vehicle
We don't have reviewed vehicle-specific evidence for P0195 yet. The causes and tests above apply across vehicles.
Related codes
No curated relationships for P0195 yet.
P0195 questions
Is it safe to drive with P0195?
The sources list a check engine light and poorer fuel economy as the usual signs, but they do not rate urgency. Have it read and checked soon.
Sources and review
- P0195 - Engine oil temperature sensor circuit malfunction
- On-Board Diagnostic Trouble Codes (generic code title list)
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error