2001 INFINITI QX4 Factory Service Manual

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INFINITI QX4 2001  Factory Service Manual Wiring DiagramNBEC0056
MEC942C
DTC P0100 MASS AIR FLOW SENSOR (MAFS)
Wiring Diagram
EC-154

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INFINITI QX4 2001  Factory Service Manual Diagnostic ProcedureNBEC0057
1 INSPECTION START
Which malfunction (A, B, C, D or E) is duplicated?
MTBL0373
Type I or Type II
Type I©GO TO 3.
Type II©GO TO 2.
2 CHECK INTAKE SYSTEM
Check the followi

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INFINITI QX4 2001  Factory Service Manual 4 CHECK MAFS POWER SUPPLY CIRCUIT
1. Disconnect mass air flow sensor (MAFS) harness connector.
SEF960Y
2. Turn ignition switch ªONº.
3. Check voltage between MAFS terminals 2, 4 and ground with CONS

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INFINITI QX4 2001  Factory Service Manual 7 CHECK MAFS INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between MAFS terminal 1 and ECM terminal 61.
Refer to Wiring Diagram.
Continuity should exist.
2. Also check harness fo

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INFINITI QX4 2001  Factory Service Manual SEF052V
SEF946SB
Component DescriptionNBEC0725The absolute pressure sensor detects ambient barometric pressure
and sends the voltage signal to the ECM. As the pressure
increases, the voltage rises.
EC

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INFINITI QX4 2001  Factory Service Manual Possible CauseNBEC0728IHarness or connectors
(Absolute pressure sensor circuit is open or shorted.)
IAbsolute pressure sensor
DTC Confirmation ProcedureNBEC0729NOTE:
If ªDTC Confirmation Procedureº

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INFINITI QX4 2001  Factory Service Manual Wiring Diagram=NBEC0730
MEC943C
DTC P0105 ABSOLUTE PRESSURE SENSOR
Wiring Diagram
EC-160

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INFINITI QX4 2001  Factory Service Manual Diagnostic ProcedureNBEC0731
1 RETIGHTEN GROUND SCREWS
1. Turn ignition switch ªOFFº.
2. Loosen and retighten engine ground screws.
SEF959Y
©GO TO 2.
2 CHECK ABSOLUTE PRESSURE SENSOR CONNECTOR FOR