engine INFINITI QX4 2001 Factory Service Manual

INFINITI QX4 2001 Factory Service Manual QX4 2001 INFINITI INFINITI https://www.carmanualsonline.info/img/42/57027/w960_57027-0.png INFINITI QX4 2001 Factory Service Manual

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INFINITI QX4 2001  Factory Service Manual DIAGNOSTIC PROCEDURENBEC0049
1 INSPECTION START
Start engine.
Is engine running?
YesorNo
Ye s©GO TO 9.
No©GO TO 2.
2 CHECK ECM POWER SUPPLY CIRCUIT-I
1. Turn ignition switch ªOFFº and then ªONº.

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INFINITI QX4 2001  Factory Service Manual 9 CHECK ECM POWER SUPPLY CIRCUIT-II
1. Stop engine.
2. Check voltage between ECM terminal 67 and ground with CONSULT-II or tester.
SEF293X
OK or NG
OK©GO TO 11.
NG©GO TO 10.
10 DETECT MALFUNCTIONING

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INFINITI QX4 2001  Factory Service Manual 15 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors E1, M1
IHarness connectors M94, F27
I10A fuse
©Repair harness or connectors.
16 CHECK HARNESS CONTINUITY BETWEEN ECM RELAY AND E

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INFINITI QX4 2001  Factory Service Manual SEF958Y
Component DescriptionNBEC0050The mass air flow sensor is placed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. It consists of a ho

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INFINITI QX4 2001  Factory Service Manual On Board Diagnosis LogicNBEC0053Malfunction is detected when
(Malfunction A)an excessively high voltage from the sensor is
sent to ECM when engine is not running,
(Malfunction B)an excessively low vol

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INFINITI QX4 2001  Factory Service Manual SEF058Y
PROCEDURE FOR MALFUNCTION ANBEC0054S01With CONSULT-IINBEC0054S01011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 6 seconds.
4) If 1st trip DT

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INFINITI QX4 2001  Factory Service Manual SEF243Y
SEF175Y
PROCEDURE FOR MALFUNCTION DNBEC0054S04CAUTION:
Always drive vehicle at a safe speed.
With CONSULT-IINBEC0054S04021) Turn ignition switch ªONº.
2) Start engine and warm it up to norma

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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 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