P0100 indicates the engine computer has detected a malfunction in the electrical circuit for the Mass Air Flow (MAF) or Volume Air Flow sensor. This is a circuit fault, meaning the sensor signal is missing, implausible, or outside the expected voltage/frequency range rather than simply a minor airflow reading error.
Internal failure of the sensing element or sensor electronics is the most common cause. The sensor may stop producing a valid signal or send an out-of-range voltage.
Damaged, corroded, loose, or chafed wiring at the MAF connector can interrupt power, ground, or signal. This is common and should be checked before replacing the sensor.
The MAF sensor requires proper battery voltage and ground. A blown fuse, poor ground, or upstream wiring fault can prevent the sensor from operating.
Oil, dirt, or debris on the sensing element can cause an implausible signal. This is less likely for a pure circuit code but possible on some vehicles.
Rare. The PCM may fail to read the signal correctly, but this should only be considered after all wiring, power/ground, and sensor checks are verified.
Almost never. PCM failure is very rare for this code. Verify the MAF sensor, connector, wiring, fuses, and power/ground first.
Not directly. A dirty filter may affect airflow readings but usually will not trigger a circuit code. Focus on the sensor and its electrical circuit first.
You may be able to drive, but the engine can run poorly, hesitate, or stall. Diagnose it soon to avoid drivability and emissions problems.
Cleaning may help if contamination is affecting the signal, but P0100 is a circuit fault. If cleaning does not restore a valid signal, the sensor or wiring is likely faulty.