Code Definition

P0103 — Mass Air Flow Circuit High

System: Powertrain  |  Type: Generic (OBD-II Standard)  |  Make: Generic

About P0103

P0103 is a generic (obd-ii standard) powertrain diagnostic trouble code. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.

When P0103 is stored, the module has detected a signal or supply voltage lower than the expected operating range; and a signal or supply voltage higher than the expected operating range.

Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.

Because P0103 is a generic OBD-II code, its base definition is shared across manufacturers. The specific diagnostic steps, reference values, and repair procedures can vary by vehicle, and the TaT Diagnostic Assistant includes verified procedures submitted by working technicians.

Code Information

The mass air flow (MAF) sensor measures the mass of air entering the engine and is one of the primary inputs the ECM uses to calculate fuel delivery and ignition timing. DTC P0103 is set when the ECM detects the MAF signal is higher than the range expected for the current engine speed and load, a high input. On an analog sensor the signal voltage rises with airflow, and on a frequency type sensor it rises in Hz, so a signal that reads too high tells the ECM that more air is entering than is physically realistic. This usually comes from a circuit fault such as a short to voltage, a contaminated...

Join TaT to view the complete code information and diagnostic details.

Quick Facts