P0103 — Mass or Volume Air Flow "A" Circuit High Input
Category: Powertrain Severity: Medium
Updated:
DTC code P0103 means: Mass or Volume Air Flow "A" Circuit High Input. It falls under the "Powertrain" category, with an estimated severity of Medium. Common causes include failed MAF sensor, signal wire shorted to voltage and poor sensor ground; it's worth confirming the diagnosis before replacing parts.
Possible causes
- Failed MAF sensor
- Signal wire shorted to voltage
- Poor sensor ground
- Misfitted or over-oiled air filter
Symptoms
- Rough idle
- Black smoke
- Higher fuel consumption
- Hesitation
How to diagnose it step by step
- Check the air filter and duct.
- Measure MAF signal engine-off and at idle.
- Check ground and supply.
- Replace the MAF if the signal is wrong.
How to fix it
Check MAF signal voltage at idle (typically 0.6–1.2 V). If it reads high with the engine off, check wiring and ground; if wiring is fine, replace the MAF.
Estimated repair cost
MAF sensor: $100–300.
Frequently asked questions
What does DTC code P0103 mean?
Mass or Volume Air Flow "A" Circuit High Input.
Is code P0103 serious?
Severity Medium. Not urgent, but worth diagnosing to avoid bigger damage.
Can I keep driving with code P0103?
You can drive, but with higher fuel use and poorer response.
Related codes
P0102 P0101 P0106 P0107 P0108 P0110 P0112 P0113 P0115 P0116
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🛒 Buy mass air flow sensor (MAF) at Autodoc (affiliate link)