DTC P0103: MAF Sensor Circuit - High Frequency: Description

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The Mass Airflow (MAF) sensor is an airflow meter that measures the amount of air entering the engine. The Powertrain Control Module (PCM) uses the MAF sensor frequency signal in order to provide the correct fuel delivery for a wide range of engine speeds and loads. A small quantity of air entering the engine indicates a deceleration or idle. A large quantity of air entering the engine indicates an acceleration or high load condition. The MAF sensor has the following circuits:

An ignition 1 voltage circuit.
A ground circuit.
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 air flow through the sensor bore. The frequency varies within a range of around 2,000 Hertz at idle to about 10,000 Hertz at maximum engine load. DTC P0103 sets if the PCM detects a frequency signal higher than the possible range of a properly operating sensor.