2001 INFINITI QX4 Factory Service Manual

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INFINITI QX4 2001  Factory Service Manual Diagnostic ProcedureNBEC0387
1 INSPECTION START
Turn ignition switch to ªSTARTº.
Is any cylinder ignited?
YesorNo
Ye s©GO TO 2.
No©GO TO 3.
2 CHECK OVERALL FUNCTION
With CONSULT-II
1. Start engine

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INFINITI QX4 2001  Factory Service Manual 3 CHECK INJECTOR POWER SUPPLY CIRCUIT
1. Turn ignition switch ªOFFº.
SEF023Z
2. Turn ignition switch ªONº.
3. Check voltage between injector terminal 1 and ground with CONSULT-II or tester.
SEF364

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INFINITI QX4 2001  Factory Service Manual 6 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors F100, F5
IHarness for open or short between harness connector F5 and ECM
IHarness for open or short between harness connector F100

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INFINITI QX4 2001  Factory Service Manual CONSULT-II Reference Value in Data Monitor
Mode
NBEC0388Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
START SIGNALIIgnition switch: ON,START,ON OFF,ON,OFF
ECM Terminals

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INFINITI QX4 2001  Factory Service Manual Wiring Diagram=NBEC0390
MEC975C
START SIGNAL
Wiring Diagram
EC-622

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INFINITI QX4 2001  Factory Service Manual Diagnostic ProcedureNBEC0391
1 INSPECTION START
Do you have CONSULT-II?
YesorNo
Ye s©GO TO 2.
No©GO TO 3.
2 CHECK OVERALL FUNCTION
With CONSULT-II
1. Turn ignition switch ªONº.
2. Check ªSTART SI

Page 1159 of 2395

INFINITI QX4 2001  Factory Service Manual 5 CHECK FUSE
1. Turn ignition switch ªOFFº.
2. Disconnect 7.5A fuse.
3. Check if 7.5A fuse is OK.
OK or NG
OK©GO TO 6.
NG©Replace 7.5A fuse.
6 CHECK START SIGNAL INPUT SIGNAL CIRCUIT FOR OPEN AND

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INFINITI QX4 2001  Factory Service Manual System DescriptionNBEC0392
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed (POS signal)
Fuel pump
controlFuel pump relay Crankshaft position sensor (REF)