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. Refer to REMOVAL , Mass Air Flow and Intake Air Temperature Sensor.
Connect terminal No. 3 to the battery positive terminal and terminal No. 4 to the battery ground terminal, terminal No. 5 to the circuit tester positive terminal and No. 4 to the circuit tester ground terminal.

Fig 2: Connecting Terminal No. 3 To Battery Positive Terminal And Terminal No. 4 To Battery Ground Terminal
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Check the voltage changes when air is blown to the mass air flow sensor unit in arrow direction.

Fig 3: Checking Voltage To Mass Air Flow Sensor

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