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GF07.07-P-4118-02C Hot Film Mass Air Flow Sensor Function



GF07.07-P-4118-02C Hot Film Mass Air Flow Sensor Function







The electronics in the hot film mass air flow sensor (B2/5) controls the temperature of the heating resistor (RH) by means of a variable voltage so that its temperature is 160 degrees C above the intake air temperature detected by the temperature resistor (RL). The temperature of the heating resistor (RH) is detected by the sensor resistor (RS).

If a change in temperature occurs because of an increase or reduction in the air flow, the electronics (9/5) adjusts the voltage of the heating resistor (RH) until the temperature difference is again achieved. This control voltage is used by the engine control module as a measure for the metered air mass.