Range check

P115A,P115B 

Depending on the engine design the mass airflow must lie within a valid range during all engine conditions.

If the measured mass airflow from the MAF sensor lies below the valid minimum mass airflow for a calibrated period of time, a minimum fault HFMR is set.

If the measured mass airflow from the MAF sensor exceeds the valid maximum mass airflow for a calibrated period of time, a maximum fault HFMR is set.