What P0102 means
Mass or Volume Air Flow Sensor A Circuit Low
How to diagnose
- Read freeze frame data. When P0102 set, your ECU snapshotted every sensor at that moment. This tells you what the car was doing when the fault triggered — RPM, load, coolant temp, throttle position, fuel trims. Almost always enough info to figure out the cause without further testing.
- Check for related codes. If you have P0102 plus other codes, fix the earliest one in the chain first — a single root cause often triggers multiple codes.
- Cheap fixes first. For most codes, the order is: inspect connectors + wiring (free), check for vacuum leaks (cheap), replace sensor (moderate), replace mechanical part (expensive). Follow that ladder before dropping money on parts.
Manufacturer-specific descriptions
Different manufacturers use P0102 for slightly different failure modes:
| AUDI | The Mass Airflow Sensor (MAF) Sensor is unplugged or the wiring is damaged, Loose or corroded electrical terminals in the MAF Sensor circuit, Faulty MAF Sensor |
| BMW | Mass or Volume Air Flow Circuit Low Input |
| FORD | MAF Circuit Low Input |
| GM | Mass Air Flow (MAF) Sensor Circuit Low Frequency |
| HONDA | Mass Airflow (MAF) Sensor Circuit Low Voltage |
| MITSUBISHI | Mass or Volume Air Flow Circuit low Input; AFS low input |
| NISSAN | Mass or Volume Air Flow Circuit low Input |
| VOLKSWAGEN | Mass Air Flow (MAF) Sensor Circuit Low Frequency |
Read P0102 on your own car
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