P0103
Mass or Volume Air Flow Circuit High Input
The MAF sensor reports an air flow value above the plausible maximum for current engine speed and load. Often indicates a sensor that is failing in a way that produces excess output, or a short to supply voltage in the signal path.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: easy
Common causes
Ordered by how often each turns out to be the cause.
- MAF sensor failedCommon
- Signal wire shorted to supply voltagePossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Mass Air Flow Sensor
- Mass Air Flow Sensor Wiring
P0103 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.