01 Why Spare Parts Shops Are One of the Most Profitable Busine… • 02 B0004 - PCM Discrete Input Speed Signal Not Present • 03 Milling Machine Basics: A Complete Guide for Beginners • 04 What Happens When the Throttle Body Gets Dirty • 05 Unveiling the Mystery of Gaskets: Your Key to Automotive Se… • 06 How do driverless cars navigate without road markings? • 07 This Overlooked Factor In Car Engines Might Be The Real Rea… • 08 Ignoring These Fuel Usage Signs Can Lead to Expensive Engin… • 09 This Is Why Your Car’s Exhaust Smells Like Sulfur • 10 Your Car Might Be Heading For Total Failure Because Of One … •

DTC codes / P01xx · Fuel and air metering / P0195

P0195Engine Oil Temperature Sensor Malfunction

P0195 means the powertrain control module (PCM) has detected a fault in the engine oil temperature sensor circuit, so the signal it receives is outside the expected range for the current operating conditions. The PCM compares the oil temperature sensor voltage to a calculated model and sets this code when the reading is implausibly high, low, or intermittent.

SystemPowertrain
Code typeGeneric (all makes)
SeverityLow
Fix difficultyIntermediate
AreaFuel and air metering

Symptoms you may notice

  • Illuminated check engine light, often with no other noticeable symptoms
  • Oil temperature gauge or dashboard display reading incorrectly or not moving
  • Rough running or poor fuel economy if the PCM substitutes a default oil temperature value
  • Hard starting or stalling in extreme cold if the sensor reads warmer than actual
  • Reduced engine power or limp mode on some vehicles that rely on oil temperature for protection strategies

Common causes, most likely first

  1. Faulty engine oil temperature sensor itself, worn or contaminated internally
  2. Damaged or corroded sensor connector pins or terminals
  3. Open or shorted wiring in the sensor circuit, often from chafing or heat damage
  4. Poor ground connection at the sensor or engine block
  5. PCM internal fault or software issue misinterpreting a valid signal
  6. Low oil level or severely degraded oil causing the sensor to read outside normal range

How to diagnose and fix it

  1. Check engine oil level and condition; top up or change oil if it is low or heavily contaminated
  2. Inspect the oil temperature sensor connector and wiring for corrosion, looseness, or chafing
  3. Measure sensor resistance with a multimeter and compare to the manufacturer's temperature-resistance chart
  4. Backprobe the sensor signal wire at the PCM and verify voltage changes as the engine warms
  5. Check for continuity and resistance to ground on the sensor ground circuit
  6. Replace the engine oil temperature sensor if resistance is out of specification or the signal is erratic
  7. Clear the code and perform a road test to confirm the repair and ensure the code does not return

What the oil temperature sensor really does

  • Many engines use the oil temperature sensor to validate the coolant temperature sensor during cold starts, so a failing oil sensor can cause a false coolant sensor code.
  • A common misdiagnosis is replacing the coolant temperature sensor when the oil temperature sensor is actually skewing the PCM's temperature model.
  • On some vehicles the oil temperature sensor is integrated into the oil level sensor or oil pressure sensor, so the entire assembly must be replaced.
  • Wiring harness damage near hot exhaust components is a frequent cause that is missed when only the sensor is checked.
  • The PCM may use a default oil temperature value when the sensor fails, allowing the engine to run almost normally and hiding the fault from the driver.

Can I keep driving with P0195?

You can usually continue driving with P0195 because the PCM substitutes a default oil temperature value, but avoid heavy towing or sustained high-speed driving until the fault is repaired. If the engine runs roughly or enters limp mode, have it diagnosed promptly.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage