Page 845 of 2395
DTC Confirmation ProcedureNBEC0179NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
SEF174Y
WITH CONSULT-IINBEC0179S011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 10 seconds.
If the result is NG, go to ªDiagnostic Procedureº, EC-312.
If the result is OK, go to following step.
4) Check ªCOOLAN TEMP/Sº value.
If ªCOOLAN TEMP/Sº is less than 60ÉC (140ÉF), the result will
be OK.
If ªCOOLAN TEMP/Sº is above 60ÉC (140ÉF), go to the follow-
ing step.
5) Cool engine down until ªCOOLAN TEMP/Sº is less than 60ÉC
(140ÉF).
6) Wait at least 10 seconds.
7) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-312.
WITH GSTNBEC0179S02Follow the procedure ªWith CONSULT-IIº above.
DTC P0180 FUEL TANK TEMPERATURE SENSOR
DTC Confirmation Procedure
EC-310
Page 856 of 2395

SEF213Y
DTC Confirmation ProcedureNBEC0183CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
WITH CONSULT-IINBEC0183S011) Turn ignition switch ªONº, and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and warm it up to normal operating temperature.
3) Turn ignition switch ªOFFº and wait at least 10 seconds.
4) Start engine again and drive at 1,500 to 3,000 rpm for at least
3 minutes.
Hold the accelerator pedal as steady as possible.
NOTE:
Refer to the freeze frame data for the test driving conditions.
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-321.
WITH GSTNBEC0183S02Follow the procedure ªWith CONSULT-IIº above.
Diagnostic ProcedureNBEC0184
1 CHECK FOR INTAKE AIR LEAK
1. Start engine and run it at idle speed.
2. Listen for the sound of the intake air leak.
OK or NG
OK©GO TO 2.
NG©Discover air leak location and repair.
2 CHECK FOR EXHAUST SYSTEM CLOGGING
1. Stop engine and visually check exhaust tube, three way catalyst and muffler for dents.
OK or NG
OK©GO TO 3.
NG©Repair or replace it.
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DTC P0300 - P0306 NO.6-1CYLINDER MISFIRE, MULTIPLE CYLINDER
MISFIRE
DTC Confirmation Procedure
EC-321
Page 860 of 2395

11 CHECK HEATED OXYGEN SENSOR 1 (FRONT)
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªMANU TRIGº and ªHI SPEEDº in ªDATA MONITORº mode with CONSULT-II, and select ªHO2S1 (B1)/(B2)º and
ªHO2S1 MNTR (B1)/(B2)º.
3. Hold engine speed at 2,000 rpm under no load during the following steps.
4. Touch ªRECORDº on CONSULT-II screen.
SEF967Y
5. Check the following.
IªHO2S1 MNTR (B1)/(B2)º in ªDATA MONITORº mode changes from ªRICHº to ªLEANº to ªRICHº 5 times in 10 seconds.
5 times (cycles) are counted as shown left:
SEF647Y
IªHO2S1 (B1)/(B2)º voltage goes above 0.6V at least once.
IªHO2S1 (B1)/(B2)º voltage goes below 0.3V at least once.
IªHO2S1 (B1)/(B2)º voltage never exceeds 1.0V.
SEF648Y
CAUTION:
Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
OK or NG
OK©GO TO 14.
NG©GO TO 13.
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DTC P0300 - P0306 NO.6-1CYLINDER MISFIRE, MULTIPLE CYLINDER
MISFIRE
Diagnostic Procedure (Cont'd)
EC-325
Page 863 of 2395

SEF332I
Component DescriptionNBEC0185The knock sensor is attached to the cylinder block. It senses
engine knocking using a piezoelectric element. A knocking vibration
from the cylinder block is sensed as vibrational pressure. This
pressure is converted into a voltage signal and sent to the ECM.
Freeze frame data will not be stored in the ECM for the knock
sensor. The MIL will not light for knock sensor malfunction.
The knock sensor has one trip detection logic.
ECM Terminals and Reference ValueNBEC0663Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
93 W Knock sensor[Engine is running]
IIdle speedApproximately 2.5V
On Board Diagnosis LogicNBEC0187Malfunction is detected when an excessively low or high voltage
from the knock sensor is sent to ECM.
Possible CauseNBEC0491IHarness or connectors
(The knock sensor circuit is open or shorted.)
IKnock sensor
SEF058Y
DTC Confirmation ProcedureNBEC0188NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that bat-
tery voltage is more than 10V at idle.
DTC P0325 KNOCK SENSOR (KS)
Component Description
EC-328
Page 864 of 2395
WITH CONSULT-IINBEC0188S011) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II
2) Start engine and run it for at least 5 seconds at idle speed.
3) If DTC is detected, go to ªDiagnostic Procedureº, EC-331.
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DTC P0325 KNOCK SENSOR (KS)
DTC Confirmation Procedure (Cont'd)
EC-329
Page 871 of 2395
SEF058Y
DTC Confirmation ProcedureNBEC0194NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that bat-
tery voltage is more than 10.5V.
WITH CONSULT-IINBEC0194S011) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II.
2) Crank engine for at least two seconds.
3) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-338.
WITH GSTNBEC0194S02Follow the procedure ªWith CONSULT-IIº above.
DTC P0335 CRANKSHAFT POSITION SENSOR (CKPS) (POS)
DTC Confirmation Procedure
EC-336
Page 878 of 2395
![INFINITI QX4 2001 Factory Service Manual Possible CauseNBEC0494IHarness or connectors
[The camshaft position sensor (PHASE) circuit is open or
shorted.]
ICamshaft position sensor (PHASE)
IStarter motor (Refer to SC section.)
IStarting system INFINITI QX4 2001 Factory Service Manual Possible CauseNBEC0494IHarness or connectors
[The camshaft position sensor (PHASE) circuit is open or
shorted.]
ICamshaft position sensor (PHASE)
IStarter motor (Refer to SC section.)
IStarting system](/manual-img/42/57027/w960_57027-877.png)
Possible CauseNBEC0494IHarness or connectors
[The camshaft position sensor (PHASE) circuit is open or
shorted.]
ICamshaft position sensor (PHASE)
IStarter motor (Refer to SC section.)
IStarting system circuit (Refer to SC section.)
IDead (Weak) battery
DTC Confirmation ProcedureNBEC0200NOTE:
IPerform ªPROCEDURE FOR MALFUNCTION Aº first. If 1st
trip DTC cannot be confirmed, perform ªPROCEDURE
FOR MALFUNCTION B AND Cº.
IIf ªDTC Confirmation Procedureº has been previously
conducted, always turn ignition switch ªOFFº and wait at least
10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that bat-
tery voltage is more than 10.5V at idle.
SEF013Y
PROCEDURE FOR MALFUNCTION ANBEC0200S01With CONSULT-IINBEC0200S01011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Crank engine for at least 2 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-345.
With GSTNBEC0200S0102Follow the procedure ªWith CONSULT-IIº above.
SEF058Y
PROCEDURE FOR MALFUNCTION B AND CNBEC0200S02With CONSULT-IINBEC0200S02011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and run it for at least 2 seconds at idle speed.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-345.
With GSTNBEC0200S0202Follow the procedure ªWith CONSULT-IIº above.
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DTC P0340 CAMSHAFT POSITION SENSOR (CMPS) (PHASE)
Possible Cause
EC-343
Page 883 of 2395

SEF344Z
DTC Confirmation ProcedureNBEC0215
SEF345Z
SEF560X
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
WITH CONSULT-IINBEC0215S01TESTING CONDITION:
IOpen engine hood before conducting the following proce-
dure.
IDo not hold engine speed for more than the specified
minutes below.
1) Turn ignition switch ªONº.
2) Select ªDTC & SRT CONFIRMATIONº then ªSRT WORK SUP-
PORTº mode with CONSULT-II.
3) Start engine.
4) Rev engine up to 3,000±500 rpm and hold it for 3 consecutive
minutes then release the accelerator pedal completely.
5) Wait 5 seconds at idle.
6) Rev engine up to 2,500±500 rpm and maintain it until ªINCMPº
of CATALYST changes to ªCMPLTº (It will take approximately
5 minutes).
If not ªCMPLTº, stop engine and cool it down to less than 70ÉC
(158ÉF) and then retest from step 1.
7) Select ªSELF-DIAG RESULTSº mode with CONSULT-II.
8) Confirm that the 1st trip DTC is not detected.
If the 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-349.
SEF329X
SEF330X
Overall Function CheckNBEC0216Use this procedure to check the overall function of the warm-up
three way catalyst. During this check, a 1st trip DTC might not be
confirmed.
CAUTION:
Always drive vehicle at a safe speed.
WITH GSTNBEC0216S011) Start engine and drive vehicle at a speed of more than 70 km/h
(43 MPH) for 2 consecutive minutes.
2) Stop vehicle with engine running.
3) Set voltmeters probes between ECM terminals 63 [heated oxy-
gen sensor 1 (front) right bank signal], 62 [heated oxygen
sensor 1 (front) left bank signal] and engine ground, and ECM
terminals 72 [heated oxygen sensor 2 (rear) right bank signal],
71 [heated oxygen sensor 2 (rear) left bank signal] and engine
ground.
4) Keep engine speed at 2,000 rpm constant under no load.
5) Make sure that the voltage switching frequency (high & low)
between ECM terminals 72 and engine ground, or 71 and
engine ground is very less than that of ECM terminals 63 and
engine ground, or 62 and engine ground.
Switching frequency ratio = A/B
DTC P0420 (RIGHT BANK, -B1), P0430 (LEFT BANK, -B2) THREE WAY
CATALYST FUNCTION
DTC Confirmation Procedure
EC-348