ECO mode INFINITI QX4 2001 Factory Repair Manual
Page 714 of 2395
SEF305X
With GST=NBEC0078S03021) Start engine and warm it up to normal operating temperature.
2) Maintain the following conditions for at least 10 consecutive
seconds.
Gear position Suitable position
Engine speed More than 2,000 rpm
Engine coolant temperature More than 70ÉC (158ÉF)
Voltage between ECM termi-
nal 91 (Mass air flow sensor
signal) and groundMore than 3.2V
3) Select ªMODE 7º with GST.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-181.
GI
MA
EM
LC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P0120 THROTTLE POSITION SENSOR
DTC Confirmation Procedure (Cont'd)
EC-179
Page 718 of 2395
8 CHECK THROTTLE POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 91 and throttle position sensor terminal 2.
Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK (With CONSULT-II)©GO TO 9.
OK (Without CONSULT-
II)©GO TO 10.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
9 CHECK THROTTLE POSITION SENSOR
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine (ignition switch OFF).
3. Remove the vacuum hose connected to the throttle opener.
4. Connect suitable vacuum hose to the vacuum pump and the opener.
5. Apply vacuum [more than ±40.0kPa (±300mmHg, ±11.81inHg)] until the throttle drum becomes free from the rod of the
throttle opener.
SEF793W
6. Turn ignition switch ON.
7. Select ªDATA MONITORº mode with CONSULT-II.
8. Check voltage of ªTHRTL POS SENº under the following conditions.
Voltage measurement must be made with throttle position sensor installed in vehicle.
SEF062Y
OK or NG
OK©GO TO 12.
NG©GO TO 11.
GI
MA
EM
LC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P0120 THROTTLE POSITION SENSOR
Diagnostic Procedure (Cont'd)
EC-183
Page 723 of 2395
Possible CauseNBEC0431IHarness or connectors
(High resistance in the circuit)
IEngine coolant temperature sensor
IThermostat
SEF174Y
DTC Confirmation ProcedureNBEC0083CAUTION:
Be careful not to overheat engine.
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-IINBEC0083S011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Check that ªCOOLAN TEMP/Sº is above 10ÉC (50ÉF).
If it is above 10ÉC (50ÉF), the test result will be OK.
If it is below 10ÉC (50ÉF), go to following step.
4) Start engine and run it for 65 minutes at idle speed.
If ªCOOLAN TEMP/Sº increases to more than 10ÉC (50ÉF)
within 65 minutes, stop engine because the test result will
be OK.
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-190.
WITH GSTNBEC0083S02Follow the procedure ªWITH CONSULT-IIº above.
DTC P0125 ENGINE COOLANT TEMPERATURE SENSOR (ECTS)
Possible Cause
EC-188
Page 727 of 2395
SEF463R
SEF288D
Component DescriptionNBEC0086The heated oxygen sensor 1 (front) is placed into the front tube. It
detects the amount of oxygen in the exhaust gas compared to the
outside air. The heated oxygen sensor 1 (front) has a closed-end
tube made of ceramic zirconia. The zirconia generates voltage from
approximately 1V in richer conditions to 0V in leaner conditions.
The heated oxygen sensor 1 (front) signal is sent to the ECM. The
ECM adjusts the injection pulse duration to achieve the ideal air-
fuel ratio. The ideal air-fuel ratio occurs near the radical change
from 1V to 0V.
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0087Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 (B1)
HO2S1 (B2)
IEngine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V+,Approx. 0.6 - 1.0V
HO2S1 MNTR
(B1)
HO2S1 MNTR
(B2)LEAN+,RICH
Changes more than 5 times during
10 seconds.
ECM Terminals and Reference ValueNBEC0652Specification 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)
63 GHeated oxygen sensor
1 (front) (bank 1)[Engine is running]
IWarm-up condition
IEngine speed is 2,000 rpm.0 - Approximately 1.0V (Peri-
odically change)
SEF059V
DTC P0130, P0150 HEATED OXYGEN SENSOR 1 (FRONT) (BANK 1)/(BANK 2)
(CIRCUIT)
Component Description
EC-192
Page 729 of 2395
SEF332Z
DTC Confirmation ProcedureNBEC0090
SEF333Z
SEF645Y
CAUTION:
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.
TESTING CONDITION:
Before performing the following procedure, confirm that bat-
tery voltage is more than 11V at idle.
WITH CONSULT-IINBEC0090S011) Start engine and warm it up to normal operating temperature.
2) Select ªHO2S1 (B1)/(B2) P0130/P0150º of ªHO2S1º in ªDTC
WORK SUPPORTº mode with CONSULT-II.
3) Touch ªSTARTº.
4) Let it idle for at least 3 minutes.
NOTE:
Never raise engine speed above 3,600 rpm after this step. If
the engine speed limit is exceeded, return to step 4.
5) When the following conditions are met, ªTESTINGº will be dis-
played on the CONSULT-II screen. Maintain the conditions
continuously until ªTESTINGº changes to ªCOMPLETEDº. (It
will take approximately 10 to 60 seconds.)
ENG SPEED 1,500 - 2,800 rpm
Vehicle speed 70 - 100 km/h (43 - 62 MPH)
B/FUEL SCHDL 3.0 - 10 msec
Selector lever Suitable position
If ªTESTINGº is not displayed after 5 minutes, retry from
step 2.
6) Make sure that ªOKº is displayed after touching ªSELF-DIAG
RESULTSº. If ªNGº is displayed, refer to ªDiagnostic
Procedureº, EC-198.
During this test, P1148 and P1168 may be stored in ECM.
SEF308XB
Overall Function CheckNBEC0091Use this procedure to check the overall function of the heated oxy-
gen sensor 1 (front) circuit. During this check, a 1st trip DTC might
not be confirmed.
WITH GSTNBEC0091S011) Start engine and warm it up to normal operating temperature.
2) Set voltmeter probes between ECM terminal 63 (HO2S1 bank
1 right signal) or 62 (HO2S1 bank 2 left signal) and engine
ground.
DTC P0130, P0150 HEATED OXYGEN SENSOR 1 (FRONT) (BANK 1)/(BANK 2)
(CIRCUIT)
DTC Confirmation Procedure
EC-194
Page 735 of 2395
3 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 adjust ªTRIGGER POINTº to 100% in ªDATA MONITORº mode with CONSULT-II.
3. Select ªHO2S1 (B1)/(B2)º and ªHO2S1 MNTR (B1)/(B2)º.
4. Hold engine speed at 2,000 rpm under no load during the following steps.
5. Touch ªRECORDº on CONSULT-II screen.
SEF967Y
6. 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 below.
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 6.
NG©GO TO 5.
DTC P0130, P0150 HEATED OXYGEN SENSOR 1 (FRONT) (BANK 1)/(BANK 2)
(CIRCUIT)
Diagnostic Procedure (Cont'd)
EC-200
Page 737 of 2395
SEF463R
SEF288D
Component DescriptionNBEC0094The heated oxygen sensor 1 (front) is placed into the front tube. It
detects the amount of oxygen in the exhaust gas compared to the
outside air. The heated oxygen sensor 1 (front) has a closed-end
tube made of ceramic zirconia. The zirconia generates voltage from
approximately 1V in richer conditions to 0V in leaner conditions.
The heated oxygen sensor 1 (front) signal is sent to the ECM. The
ECM adjusts the injection pulse duration to achieve the ideal air-
fuel ratio. The ideal air-fuel ratio occurs near the radical change
from 1V to 0V.
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0095Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 (B1)
HO2S1 (B2)
IEngine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V+,Approx. 0.6 - 1.0V
HO2S1 MNTR
(B1)
HO2S1 MNTR
(B2)LEAN+,RICH
Changes more than 5 times during
10 seconds.
ECM Terminals and Reference ValueNBEC0653Specification 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)
63 GHeated oxygen sensor
1 (front) (bank 1)[Engine is running]
IWarm-up condition
IEngine speed is 2,000 rpm.0 - Approximately 1.0V (Peri-
odically change)
SEF059V
DTC P0131, P0151 HEATED OXYGEN SENSOR 1 (FRONT) (BANK 1)/(BANK 2)
(LEAN SHIFT MONITORING)
Component Description
EC-202
Page 739 of 2395
SEF334Z
SEF335Z
SEF651Y
WITH CONSULT-IINBEC0098S011) Start engine and warm it up to normal operating temperature.
2) Stop engine and wait at least 10 seconds.
3) Turn ignition switch ªONº and select ªHO2S1 (B1)/(B2) P0131/
P0150º of ªHO2S1º in ªDTC WORK SUPPORTº mode with
CONSULT-II.
4) Touch ªSTARTº.
5) Start engine and let it idle for at least 3 minutes.
NOTE:
Never raise engine speed above 3,600 rpm after this step. If
the engine speed limit is exceeded, return to step 5.
6) When the following conditions are met, ªTESTINGº will be dis-
played on the CONSULT-II screen. Maintain the conditions
continuously until ªTESTINGº changes to ªCOMPLETEDº. (It
will take approximately 50 seconds or more.)
ENG SPEED 1,300 - 2,800 rpm
Vehicle speed 80 - 100 km/h (50 - 62 MPH)
B/FUEL SCHDL 3 - 10 msec
Selector lever Suitable position
If ªTESTINGº is not displayed after 5 minutes, retry from
step 2.
7) Make sure that ªOKº is displayed after touching ªSELF-DIAG
RESULTSº. If ªNGº is displayed, refer to ªDiagnostic
Procedureº, EC-205.
SEF308XB
Overall Function CheckNBEC0099Use this procedure to check the overall function of the heated oxy-
gen sensor 1 (front) circuit. During this check, a 1st trip DTC might
not be confirmed.
WITH GSTNBEC0099S011) Start engine and warm it up to normal operating temperature.
2) Set voltmeter probes between ECM terminal 63 (HO2S1 bank
1 right signal) or 62 (HO2S1 bank 2 left signal) and engine
ground.
3) Check one of the following with engine speed held at 2,000
rpm constant under no load.
IThe maximum voltage is over 0.6V at least one time.
IThe minimum voltage is over 0.1V at least one time.
4) If NG, go to ªDiagnostic Procedureº, EC-205.
DTC P0131, P0151 HEATED OXYGEN SENSOR 1 (FRONT) (BANK 1)/(BANK 2)
(LEAN SHIFT MONITORING)
DTC Confirmation Procedure (Cont'd)
EC-204
Page 741 of 2395
3 CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªSELF-LEARNING CONTº in ªWORK SUPPORTº mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching ªCLEARº.
SEF968Y
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 or P0174 detected?
Is it difficult to start engine?
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch ªOFFº.
3. Disconnect mass air flow sensor harness connector, and restart and run engine for at least 5 seconds at idle speed.
4. Stop engine and reconnect mass air flow sensor harness connector.
5. Make sure 1st trip DTC P0100 is displayed.
6. Erase the 1st trip DTC memory. Refer to ªHOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATIONº,
EC-72.
7. Make sure DTC P0000 is displayed.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 or P0174 detected?
Is it difficult to start engine?
YesorNo
Ye s©Perform trouble diagnosis for DTC P0171, P0174. Refer to EC-294.
No©GO TO 4.
DTC P0131, P0151 HEATED OXYGEN SENSOR 1 (FRONT) (BANK 1)/(BANK 2)
(LEAN SHIFT MONITORING)
Diagnostic Procedure (Cont'd)
EC-206
Page 743 of 2395
5 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 adjust ªTRIGGER POINTº to 100% in ªDATA MONITORº mode with CONSULT-II.
3. Select ªHO2S1 (B1)/(B2)º and ªHO2S1 MNTR (B1)/(B2)º.
4. Hold engine speed at 2,000 rpm under no load during the following steps.
5. Touch ªRECORDº on CONSULT-II screen.
SEF967Y
6. 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 below.
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 8.
NG©GO TO 7.
DTC P0131, P0151 HEATED OXYGEN SENSOR 1 (FRONT) (BANK 1)/(BANK 2)
(LEAN SHIFT MONITORING)
Diagnostic Procedure (Cont'd)
EC-208