P0103

  • Powertrain
  • Generic (SAE)
  • Emissions
SeveritySeverity level 3 of 5: Diagnose soon.

Diagnose soon

Usually safe to drive short distances, but the fault will not clear itself and can worsen or fail an emissions test.

Standard definition

Mass or Volume Air Flow Circuit High Input

This code is in our catalogue but has not yet been through editorial review, so the guidance below is limited to what our structured data supports. We publish deeper diagnostic content only after a code has been reviewed — here is why.

In plain English

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.

A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.

Can I keep driving?
Safe to drive
Usually safe to drive short distances, but the fault will not clear itself and can worsen or fail an emissions test.
Urgency
Diagnose soon
Will it pass emissions
No
Check engine light
Solid
Clearing the light
A completed drive cycle is normally required before the monitor re-runs and the light can clear.
Likely causes
#CauseHow oftenComponent
1MAF sensor failedVery common
2Signal wire shorted to supply voltageCommon
3Connector pins corroded - high contact resistanceOccasional

Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.

Components involved
Sources
Definition
Generic code set (SAE J2012 / ISO 15031-6) via the OBDexopen database, dedicated to the public domain under CC0-1.0.
Diagnostic guidance
Written and reviewed in-house. See our editorial policy.
Review status
Awaiting review

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