The engine oil temperature sensor A is an NTC thermistor fed with 5 V through a resistor: the hotter the oil, the lower the signal voltage. The engine module uses the oil temperature for variable cam timing (Ford disables it with cold oil or a sensor fault), engine protection and the oil life monitor; many engines have no such sensor and use a calculated oil temperature instead. P0195 is the general circuit fault without telling low from high. With analogue sensors most manufacturers use P0197/P0198 instead. The documented use is Ford's 2023 diesels with a digital SENT oil temperature sensor: P0195 is set when the sensor reports a status or data fault for 5 s, while a complete loss of communication is U0667. The module then uses a substitute value (Saab: 100 °C), and functions relying on oil temperature are restricted.
High severity. Can I keep driving?If the red oil warning light comes on, stop the car in a safe place and turn off the engine. Do not continue until you have confirmed the level and pressure.
Symptoms
- Check engine light on (depending on manufacturer)
- Oil temperature display missing or fixed
- Restricted cam timing, slightly reduced power
- Oil life calculation less accurate
Most likely causes
- Connector or harness damaged, corroded or oil-soaked
- Sensor faulty internally (electronics fault on SENT sensors)
- 5 V reference or ground problem in the sensor circuit
- Control module or software
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: easy
- It affects emissions.
What each character of P0195 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 1: Air and fuel
- 95: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0195?
If the red oil warning light comes on, stop the car in a safe place and turn off the engine. Do not continue until you have confirmed the level and pressure.
What causes code P0195?
The most common causes are: connector or harness damaged, corroded or oil-soaked; sensor faulty internally (electronics fault on SENT sensors); 5 V reference or ground problem in the sensor circuit.
Related codes
- P0196Engine Oil Temperature Sensor A Range/Performance
- P0197Engine Oil Temperature Sensor A Circuit Low
- P0198Engine Oil Temperature Sensor A Circuit High
- P0199Engine Oil Temperature Sensor A Circuit Intermittent/Erratic
- P01B9Engine Oil Temperature Sensor B Circuit
- U0667Lost Communication With Engine Oil Temperature Sensor A
Sources
- law.cornell.edu: 13 CCR 1968.2
- fordservicecontent.com: obd summary diesel 2023
- saabwisonline.com: temperature sensor engine oil
- patents.google.com: en
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.