DTC P0100 - Mass Airflow (MAF) Sensor Circuit Malfunction: Condition

WARNING: This page is about a different car, the 1997 Mazda Millenia. However, it is still accessible from the selected car via links, so may be relevant.

DTC is set when input voltage from MAF sensor is less than .64 volt or greater than 4.9 volts once engine has operated (idle) for 3 seconds. Possible causes are:

MAF sensor malfunction.
Open or short circuit between terminal No. 3E on Engine Control Module (ECM) and terminal "B" on MAF sensor.
Open or short circuit between terminal No. 4A on Engine Control Module (ECM) and terminal "C" on MAF sensor.
Open or short circuit between terminal No. 4D on Engine Control Module (ECM) and terminal "A" on MAF sensor.
Throttle Position (TP) sensor malfunction.