P0102

DESCRIPTION
The Mass Air Flow (MAF) Sensor is located near the air cleaner. The sensor measures the mass of air passing through the air intake and generates a pulsed signal. The Engine Control Module (ECM) counts the pulses generated by the sensor and uses the signal to set fuel injector base pulse width and ignition timing.

To operate, the MAF sensor requires a battery voltage at sensor terminal 2, sensor supply voltage (5 V) at sensor terminal 4 and ground at sensor terminals 3. As air passes through the sensor, the sensor generates pulses at sensor terminal 5. The frequency of the pulses increases as mass air flow increases.

FAILURE CONDITIONS
The ECM will set P0102 and the Malfunction Indicator Lamp (MIL) will turn on if the MAF sensor output indicates an open circuit, or less than 0.5 grams/second for 0.5 seconds with an engine speed greater than 200 RPM during two driving cycles. This code indicates an unusually low air flow rate being read by the MAF sensor or ECM.

The ECM will set P0103 and the Malfunction Indicator Lamp (MIL) will turn on if the MAF sensor output indicates an air flow exceeding the expected flow by 2 grams/second or more during two driving cycles. This code indicates an unusually high air flow rate is being read by the MAF sensor or ECM.

Circuit Diagram:

Test Procedure Part 1:

Test Procedure Part 2: