Motronic MED 9.1
SignalWaveform and Evaluation
Oil Level
The measuring element is briefly heated via the
present oil temperature (output = high) and then
cools down again (output = low).
The oil level is calculated from the amount of time it
takes for the sensor to cool down. The calculation is
accurate to approximately 0.08 in (2 mm).
This procedure is repeated continuously. The High
times are dependent on the oil temperature and the
Low times are proportional to the oil level.
The more oil there is in the oil sump, the quicker the
sensor cools down again.
• Long cool-down time = low oil level
• Short cool-down time = normal
Fill Level Sensor
Temperature Sensor
Temperature
Fill Level
233_050
OilTemperature
During the cool-down phase of the sensor, the oil temperature signal is also transmitted.
Heating
Phase
OilTemperature
Evaluation 25 – 85 ms
233_026
35
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