The sensor consists of a wire with high specific resistance. When current flows through the wire, its resistance varies depending on whether it is in liquid or in air.
After a certain time, a certain voltage is established on the sensor terminals, which depends on how much the wire is immersed. This voltage is analyzed by a special electronic unit that controls the level indication and the output of the "minimum oil level" signal to the central liquid crystal display.
When the ignition is turned on, the central display shows the oil level in the form of "sectors" for about 30 seconds, then switches to displaying the total and daily mileage counters (that is, to the odometer function).
Note: If you start turning the daily trip meter reset knob before the timer expires, the odometer function will be activated.
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Diagnostics
If a short circuit or open circuit is detected during oil level measurement, the display will immediately switch to displaying the odometer and clock readings.
The sensor resistance should be between 6 and 20 Ohms.
If the resistance is less than 4 ohms, it is considered that the sensor is short-circuited. If the resistance is more than 22 ohms, it is considered that the sensor is open-circuited.