DTC P0102 - MAF SENSOR CIRCUIT LOW FREQUENCY GMC Envoy I

Note. For circuit reference, see WIRING DIAGRAMS - 4.3L article.

Circuit Description

Mass Airflow (MAF) sensor measures amount of air entering engine during a given time. VCM uses MAF sensor information for fuel delivery calculations. MAF sensor readings during acceleration are much higher than those during deceleration or idle.

VCM calculates what MAF sensor reading should be received from sensor under certain conditions using engine speed (RPM), throttle position, and altitude parameters. When these test conditions are met, VCM will compare its calculated MAF value to actual value received from sensor.

Condition for setting DTC

1. Engine running.
2. Engine run time greater than .4 second.
3. System voltage is at least 8 volts.
4. Conditions must be present for a period of greater than zero seconds.