Circuit Description

WARNING: This page is about a different car, the 2003 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0100 Mass Air Flow (MAF) sensor circuit diagnostic detects an out of range sensor signal. MAF sensor measures changes in intake air volume that result from changes in throttle opening and air density. Airflow measurements are used by the Powertrain Control Module (PCM) to determine engine fueling requirements.

MAF sensor is a hot wire design. A platinum hot wire and a thermistor are located in the intake air bypass passage of MAF sensor housing. Temperature of the platinum hot wire is affected by exposure to airflow and by exposure to air temperature. Platinum hot wire is maintained at a set temperature by controlling current flow through the wire. MAF sensor converts changes in current flow to a voltage signal. Voltage signal from MAF sensor enables PCM to detect changes in air density and changes in air volume.