Signal shape and setpoint values
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The hot film air mass meter has a frequency-coded output signal. The sensor is designed in such a way that return flows (dynamic pulsation in the intake pipe) can be detected and processed both with regard to their amount and direction of flow. The signal quality for the air mass is temperature-dependent. High accuracy is required to precisely determine the air mass. This is why the air mass signal received in the engine control unit must be corrected with the signal of the intake air temperature sensor.
| Item | Explanation |
|---|---|
| 1 | Period |
| 2 | Characteristic curve for hot film air mass meter |
| 3 | Air mass |
Observe the following setpoint values for the hot film air mass meter:
| Variable | Value |
|---|---|
| Voltage range | 7.5 to 17 volts |
| Maximum power consumption | Less than 0, 1 A |
| Measuring range of hot film air mass meter | -60 bis 850 kg/h |
| Measuring range of intake air temperature | -40 °C to 110 °C |
| Frequency range | 1 to 15 kHz |
| Temperature range | -40 °C to 120 °C |