Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Engine Oil Temperature Sensor, Basic Function - GF18.30-P-2000A
Engine All (4xWD, CAR)
Example of engine oil temperature sensor
Overview
This document contains information on:
- General
- Function
General
The engine oil temperature sensor detects the engine oil temperature.
Function
The engine oil temperature sensor has an integrated precision resistor with a negative temperature coefficient (NTC).
The NTC resistor changes its electrical resistance according to the engine oil temperature.
The electrical NTC resistance decreases as the temperature increases (NTC thermistor).
The resistance variation results in a voltage signal. The combustion engine control unit calculates the engine oil temperature from the voltage signal.
The combustion engine control unit permanently evaluates the voltage signal. If the engine oil temperature is too high, a power output limitation is initiated by the combustion engine control unit.
Any fault in the engine oil temperature sensor is detected by the combustion engine control unit and entered in the fault memory.
| Component descriptions | |||
| Engine oil temperature sensor, component description | Engine 656 in model 223 | GF18.30-P-2013A |
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.