A8L Quattro Sedan V8-4.2L (BVJ) (2007)
and Inspection/Scan Tool Testing and Procedures/Preliminary Check.
Start diagnosis
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Disconnect the Mass Air Flow (MAF) Sensor (G70)/Intake Air Temperature (IAT) Sensor (G42) electrical harness connector - 1 -.
Checking voltage supply
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Using a multimeter, check the Mass Air Flow (MAF) Sensor (G70)/Intake Air Temperature (IAT) Sensor (G42) electrical harness connector
terminal 2 to engine Ground (GND) for voltage.
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Crank the engine.
Specified value: battery voltage.
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Switch the ignition off.
If specified value was not obtained:
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Check the Mass Air Flow (MAF) Sensor (G70)/Intake Air Temperature (IAT) Sensor (G42) electrical harness connector terminal 2 to theEngine
Component Power Supply Relay (J757) socket 2/87 for an open circuit.
Specified value: 1.5 ohms max.
If no malfunction is detected in the wiring and if the voltage supply was OK:
Checking electrical circuit
If the manufacturers test box is being used. Perform the following step.