Checking the resistance of the air mass flow sensor when the engine is warming up (1MZ-FE V6 engine)
The air mass flow sensor is located in the intake duct. The sensor operates by measuring the resistance of a heated conductor cooled by the air flow.
1. Disconnect the electrical connector from the sensor and with the ignition on, check that battery voltage is present on the black/orange wire.
2. Connect the electrical connector to the mass air flow sensor and connect a voltmeter to the VG and VG- terminals. With the ignition on but the engine not running, the voltage should be less than 1.0 V. After the engine starts, the voltage should increase to 2 V.
3. Check the resistance between the THA and E2 terminals of the air mass sensor connector. The resistance of the sensor should change as the engine warms up.
4. To remove the air mass flow sensor, disconnect the electrical connector from it, remove the air filter housing, unscrew the 4 bolts and remove the sensor.