Circuit Description

MAF sensor uses a platinum hot wire maintained at a constant temperature. Airflow past sensor affects temperature and current flow through sensor. See Fig 1-Fig 2 . DTC P0100 is set when ECM detects an open or short circuit for 3 seconds, with engine speed around 4000 RPM. Possible causes are:

• Open or short in MAF circuit.
• Faulty MAF sensor.
• Faulty ECM.

Fig 1: Identifying MAF Operation

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Fig 2: Identifying MAF Circuit

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