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Circuit continuity check

P0100, P0102, P0103 

To detect a circuit continuity malfunction the period duration of the mass airflow signal is compared with an upper and a lower calibration limit to identify an intermitted contact. A short circuit is identified with a period duration equal to zero.

If the period duration of the mass airflow signal from the MAF sensor equals zero for a calibrated period of time, a short circuit is detected and a signal fault HFME is set.

If the period duration of the mass airflow signal from the MAF sensor lies below the lower calibration limit for a calibrated period of time, an intermitted contact (high frequency) is detected and a minimum fault HFME is set.

If the period duration of the mass airflow signal from the MAF sensor exceeds the upper calibration limit for a calibrated period of time, an intermitted contact (low frequency) is detected and a maximum fault HFME is set.