The Mass Airflow Meter (MAF) is only applicable to the 2TZ-FZE engines. The MAF uses a platinum hot wire. The hot wire air flow meter consists of a platinum hot wire, thermister and control circuit installed in a plastic housing. The hot wire air flow meter works on the principle that the hot wire and thermister are located in the intake air bypass of the housing detect any changes in the intake air temperature.
| Fig. 1: Cutaway view of the thermister in the airflow
meter
|
The hot wire is maintained at the set temperature controlling by the current flow though the hot wire. This current flow is then measured as the output voltage of the air flow meter.
