Check The Mass Air Flow Sensor Unit

Disconnect the ground cable from battery.

Fig 1: Identifying Battery Ground Cable
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Remove the mass air flow and intake air temperature sensor. Ref. to REMOVAL , Mass Air Flow and Intake Air Temperature Sensor.
Connect the battery positive terminal to terminal No. 3 and the battery ground terminal to terminal No. 4, the circuit tester positive terminal to terminal No. 5 and the circuit tester ground terminal to terminal No. 4.

Fig 2: Identifying Circuit Tester With Mass Air Flow And Intake Air Temperature Sensor Connector Terminals
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Check the voltage changes when air is blown to the mass air flow sensor unit in arrow direction.

Fig 3: Locating Mass Air Flow Sensor
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