Code P0101, MAF Sensor Circuit: Notes

The Mass Air Flow (MAF) sensor measures the flow of air which passes through it in a given time. PCM uses this information to monitor the operating condition of the engine for fuel delivery calculations. A large quantity of air movement indicates acceleration, while a small quantity indicates deceleration or idle. MAF sensor produces a frequency signal, which cannot be easily measured. Diagnose sensor using procedures on this chart.

Code P0101 will set when the following conditions are present.

• Engine is running.
• No MAF signal for over 4 seconds.

With Code P0101 set, PCM will use a default value for airflow based on throttle position, IAC motor position and engine speed. PCM will illuminate Malfunction Indicator Light (MIL).

1. This step checks to see if PCM recognizes a problem.
2. Voltage reading at sensor harness terminal "A" of less than 4 volts or greater than 6 volts indicates a fault in circuit No. 492 (Yellow wire), or poor connection.
3. Verifies that both ignition feed voltage and a good ground circuit are available.