DTC P0103: Mass Airflow Sensor Circuit High Frequency: Description

Mass Airflow (MAF) sensor is an airflow meter that measures the amount of air entering the engine. Powertrain Control Module (PCM) uses MAF sensor frequency signal in order to provide correct fuel delivery for a wide range of engine speeds and loads. A small quantity of air entering the engine indicates deceleration or idle. A large quantity of air entering the engine indicates an acceleration or high load situation. MAF sensor has an ignition 1 voltage circuit, a ground circuit and a signal circuit. The PCM applies a voltage to the sensor on the signal circuit. The sensor uses the voltage in order to produce a frequency based on inlet airflow through sensor bore. Frequency will vary within a range of about 2000 Hz at idle to about 10,000 Hz at maximum engine load. DTC P0103 will set if the PCM detects a frequency signal higher than the possible range of a normally operating sensor.

PCM monitors MAF sensor frequency and can determine if sensor is stuck low, stuck high, not providing airflow value expected for a given operating condition, or that signal variation expected during normal operation is not present.