Cool INFINITI FX35 2006 Service Manual

DTC P0125 ECT SENSOR EC-223
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Revision: 2006 December 2006 FX35/FX45
DTC Confirmation ProcedureNBS003O8
CAUTION:
Be careful not to overheat engine.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Check that “COOLAN TEMP/S” is above 10 °C (50 °F).
If it is above 10 °C (50 °F), the test result will be OK.
If it is below 10 °C (50 °F), go to following step.
4. Start engine and run it for 65 minutes at idle speed. If “COOLAN TEMP/S” increases to more than 10 °C (50 °F)
within 65 minutes, stop engine because the test result will
be OK.
5. If 1st trip DTC is detected, go to EC-223, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureNBS003O9
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-154, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-224, "
Component Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Replace engine coolant temperature sensor.
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PBIB2625E

EC-224
[VQ35DE]
DTC P0125 ECT SENSOR
Revision: 2006 December 2006 FX35/FX45
3. CHECK THERMOSTAT OPERATION
When the engine is cold [lower than 70 °C (158 °F)] condition, grasp lower radiator hose and confirm the engine
coolant does not flow.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace thermostat. Refer to CO-27, "
WATER INLET AND THERMOSTAT ASSEMBLY"
.
4. CHECK INTERMITTENT INCIDENT
Refer to EC-148, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
Refer to EC-212, "
Wiring Diagram" .
>> INSPECTION END
Component InspectionNBS003OA
ENGINE COOLANT TEMPERATURE SENSOR
Check resistance between engine coolant temperature sensor termi-
nals 1 and 2 as shown in the figure.

If NG, replace engine coolant temperature sensor.
Removal and InstallationNBS003OB
ENGINE COOLANT TEMPERATURE SENSOR
Refer to CO-27, "WATER INLET AND THERMOSTAT ASSEMBLY" .
PBIB2005E
Engine coolant temperature °C ( °F) Resistance k Ω
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
SEF012P

DTC P0127 IAT SENSOR EC-225
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Revision: 2006 December 2006 FX35/FX45
DTC P0127 IAT SENSORPFP:22630
Component DescriptionNBS003OC
The intake air temperature sensor is built into mass air flow sensor.
The sensor detects intake air temperature and transmits a signal to
the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.

*: This data is reference values and is measured between ECM terminal 34 (Intake
air temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicNBS003OD
DTC Confirmation ProcedureNBS003OE
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
CAUTION:
Always drive vehicle at a safe speed.
TESTING CONDITION:
This test may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road
test is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-II
1. Wait until engine coolant temperature is less than 90 °C (194 °F)
a. Turn ignition switch ON.
PBIB1604E
Intake air temperature ° C ( °F) Voltage* V Resistance k
Ω
25 (77) 3.30 1.800 - 2.200
80 (176) 1.22 0.283 - 0.359
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0127
0127 Intake air temperature
too high Rationally incorrect voltage from the sensor is
sent to ECM, compared with the voltage signal
from engine coolant temperature sensor.

Harness or connectors
(Intake air temperature sensor circuit is
open or shorted)

Intake air temperature sensor

EC-226
[VQ35DE]
DTC P0127 IAT SENSOR
Revision: 2006 December 2006 FX35/FX45
b. Select “DATA MONITOR” mode with CONSULT-II.
c. Check the engine coolant temperature.
d. If the engine coolant temperature is not less than 90 °C (194 °F),
turn ignition switch OFF and cool down engine.

Perform the following steps before engine coolant tempera-
ture is above 90 °C (194 °F).
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-II.
4. Start engine.
5. Hold vehicle speed at more than 70 km/h (43 MPH) for 100 con- secutive seconds.
6. If 1st trip DTC is detected, go to EC-226, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureNBS003OF
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-154, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. CHECK INTAKE AIR TEMPERATURE SENSOR
Refer to EC-227, "
Component Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Replace mass air flow sensor (with intake air temperature sensor).
3. CHECK INTERMITTENT INCIDENT
Refer to EC-148, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
Refer to EC-207, "
Wiring Diagram" .
>> INSPECTION END
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PBIB2625E

EC-228
[VQ35DE]
DTC P0128 THERMOSTAT FUNCTION
Revision: 2006 December 2006 FX35/FX45
DTC P0128 THERMOSTAT FUNCTIONPFP:21200
On Board Diagnosis LogicNBS003OI
Engine coolant temperature has not risen enough to open the thermostat even though the engine has run long
enough.
This is due to a leak in the seal or the thermostat stuck open.
DTC Confirmation ProcedureNBS003OJ
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:

For best results, perform at ambient temperature of –10 °C (14 °F) or higher.

For best results, perform at engine coolant temperature of –10 °C (14 °F) to 60 °C (140 °F).
WITH CONSULT-II
1. Replace thermostat with new one. Refer to CO-27, "WATER INLET AND THERMOSTAT ASSEMBLY" .
Use only a genuine NISSAN thermostat as a replacement. If an incorrect thermostat is used, the MIL may
come on.
2. Turn ignition switch ON.
3. Select “COOLAN TEMP/S” in “DATA MONITOR” mode with CONSULT-II.
4. Check that the “COOLAN TEMP/S” is above 60 °C (140 °F).
If it is below 60 °C (140 °F), go to following step.
If it is above 60 °C (140 °F), cool down the engine to less than
60 °C (140 °F), then retry from step 1.
5. Drive vehicle for 10 consecutive minutes under the following conditions.
If 1st trip DTC is detected, go to EC-228, "
Diagnostic Procedure"
.
WITH GST
1. Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureNBS003OK
1. CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-229, "
Component Inspection" .
OK or NG
OK >> INSPECTION END
NG >> Replace engine coolant temperature sensor.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0128
0128 Thermostat function The engine coolant temperature does not
reach to specified temperature even though
the engine has run long enough.

Thermostat

Leakage from sealing portion of thermo-
stat

Engine coolant temperature sensor
VHCL SPEED SE 80 - 120 km/h (50 - 75 MPH)
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DTC P0128 THERMOSTAT FUNCTION EC-229
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Revision: 2006 December 2006 FX35/FX45
Component InspectionNBS003OL
ENGINE COOLANT TEMPERATURE SENSOR
Check resistance between engine coolant temperature sensor termi-
nals 1 and 2 as shown in the figure.

If NG, replace engine coolant temperature sensor.
Removal and InstallationNBS003OM
ENGINE COOLANT TEMPERATURE SENSOR
Refer to CO-27, "WATER INLET AND THERMOSTAT ASSEMBLY" .
PBIB2005E
Engine coolant temperature °C ( °F) Resistance k Ω
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
SEF012P

DTC P0137, P0157 HO2S2 EC-271
[VQ35DE]
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Revision: 2006 December 2006 FX35/FX45
DTC Confirmation ProcedureNBS003U2
NOTE:
If DTC confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
TESTING CONDITION:
For better results, perform DTC WORK SUPPORT at a temperature of 0 to 30 °C (32 to 86 °F).
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-II.
2. Start engine and warm it up to the normal operating tempera- ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70 °C
(158 °F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70 °C (158 °F).
7. Open engine hood.
8. Select “HO2S2 (B1) P1147” (for DTC P0137) or “HO2S2 (B2) P1167” (for DTC P0157) of “HO2S2” in “DTC WORK SUPPORT” mode with CONSULT-II.
9. Start engine and following the instruction of CONSULT-II.
NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
10. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”. If “NG” is displayed, refer to EC-276, "
Diagnostic Procedure" .
If “CAN NOT BE DIAGNOSED” is displayed, perform the following.
a. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
b. Return to step 1.
Overall Function CheckNBS003U3
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH GST
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Set voltmeter probes between ECM terminal 74 [HO2S2 (B1) signal] or 55 [HO2S2 (B2) signal] and ground.
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PBIB2373E

EC-282
[VQ35DE]
DTC P0138, P0158 HO2S2
Revision: 2006 December 2006 FX35/FX45
DTC Confirmation ProcedureNBS004M9
Perform PROCEDURE FOR MALFUNCTION A first.
If DTC cannot be confirmed, perform PROCEDURE FOR MALFUNCTION B.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR MALFUNCTION A
With CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-II.
2. Start engine and warm it up to the normal operating tempera- ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 2 minutes.
6. If 1st trip DTC is detected, go to EC-282, "
PROCEDURE FOR
MALFUNCTION A" .
With GST
Follow the procedure “With CONSULT-II” above.
PROCEDURE FOR MALFUNCTION B
With CONSULT-II
TESTING CONDITION:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-II.
2. Start engine and warm it up to the normal operating tempera- ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70 °C
(158 °F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70 °C (158 °F).
7. Open engine hood.
8. Select “HO2S2 (B1) P1146” (for DTC P0138) or “HO2S2 (B2) P1166” (for DTC P0158) of “HO2S2” in “DTC WORK SUPPORT” mode with CONSULT-II.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0138
0138
(Bank 1)
Heated oxygen sensor
2 circuit high voltage A)
An excessively high voltage from the sen-
sor is sent to ECM.

Harness or connectors
(Heated oxygen sensor 2 circuit is
open or shorted)

Heated oxygen sensor 2
P0158
0158
(Bank 2) B)
The minimum voltage from the sensor is
not reached to the specified voltage.

Harness or connectors
(Heated oxygen sensor 2 circuit is
open or shorted)

Heated oxygen sensor 2

Fuel pressure

Fuel injector
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DTC P0138, P0158 HO2S2 EC-283
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Revision: 2006 December 2006 FX35/FX45
9. Start engine and following the instruction of CONSULT-II. NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
10. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”. If “NG” is displayed, refer to EC-282, "
PROCEDURE FOR MALFUNCTION B" .
If “CAN NOT BE DIAGNOSED” is displayed, perform the following.
a. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
b. Return to step 1.
Overall Function CheckNBS004MA
PROCEDURE FOR MALFUNCTION B
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st
trip DTC might not be confirmed.
With GST
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Set voltmeter probes between ECM terminal 55 [HO2S2 (B2) signal] or 74 [HO2S2 (B1) signal] and ground.
6. Check the voltage when revving up to 4,000 rpm under no load at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be below 0.18V at least once during this
procedure.
If the voltage can be confirmed in step 6, step 7 is not nec-
essary.
7. Keep vehicle at idling for 10 minutes, then check the voltage. Or check the voltage when coasting from 80 km/h (50 MPH) in D
position.
The voltage should be below 0.18V at least once during this
procedure.
8. If NG, go to EC-282, "
PROCEDURE FOR MALFUNCTION B" .
PBIB2372E
PBIB1607E

DTC P0139, P0159 HO2S2 EC-295
[VQ35DE]
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Revision: 2006 December 2006 FX35/FX45
DTC Confirmation ProcedureNBS003OY
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
TESTING CONDITION:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-II.
2. Start engine and warm it up to the normal operating tempera- ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70 °C
(158 °F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70 °C (158 °F).
7. Select “HO2S2 (B1) P0139” or “HO2S2 (B2) P0159” of “HO2S2” in “DTC WORK SUPPORT” mode with CONSULT-II.
8. Start engine and following the instruction of CONSULT-II.
NOTE:
It will take at most 10 minutes until “COMPLETED” is displayed.
9. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”. If “NG” is displayed, refer to EC-300, "
Diagnostic Procedure" .
If “CAN NOT BE DIAGNOSED” is displayed, perform the following.
a. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
b. Return to step 1.
Overall Function CheckNBS003OZ
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH GST
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Set voltmeter probes between ECM terminal 74 [HO2S2 (B1) signal] or 55 [HO2S2 (B2) signal] and ground.
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PBIB2374E