engine control INFINITI FX35 2007 Service Manual

EC-280
[VQ35DE]
DTC P0138, P0158 HO2S2
Revision: 2006 July 2007 FX35/FX45
DTC P0138, P0158 HO2S2PFP:226A0
Component DescriptionNBS003ON
The heated oxygen sensor 2 (HO2S2), after three way catalyst 1,
monitors the oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air-fuel ratio is controlled to stoichiometric, by the sig-
nal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1V in richer conditions to 0V in leaner condi-
tions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
CONSULT-II Reference Value in Data Monitor ModeNBS003OO
Specification data are reference values.
On Board Diagnosis LogicNBS004M8
The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/
F) sensor 1. The oxygen storage capacity of the three way catalyst 1 causes the longer switching time.
MALFUNCTION A
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the voltage is unusually high during the various driving con-
dition such as fuel-cut.
MALFUNCTION B
To judge the malfunctions of heated oxygen sensor 2, ECM monitors
whether the minimum voltage of sensor is sufficiently low during the
various driving condition such as fuel-cut.
SEF327R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)

Revving engine from idle to 3,000 rpm quickly after the following condi-
tions are met
–Engine: After warming up
–Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no load 0 - 0.3V
←→ Approx. 0.6 -
1.0V
HO2S2 MNTR(B1)
HO2S2 MNTR(B2) LEAN
←→ RICH
PBIB1848E
PBIB2376E

DTC P0138, P0158 HO2S2 EC-289
[VQ35DE]
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Revision: 2006 July 2007 FX35/FX45
2. CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed. Is the 1st trip DTC P0172 or P0175 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 OFF.
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 con- nector.
5. Make sure DTC P0102 is displayed.
6. Erase the DTC memory. Refer to EC-66, "
HOW TO ERASE
EMISSION-RELATED DIAGNOSTIC INFORMATION" .
7. Make sure DTC P0000 is displayed.
8. Run engine for at least 10 minutes at idle speed. Is the 1st trip DTC P0172 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0172, P0175. Refer to EC-316, "DTC P0172, P0175 FUEL
INJECTION SYSTEM FUNCTION" .
No >> GO TO 3.
3. CHECK HEATED OXYGEN SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between ECM terminal 78 and HO2S2 terminal 1.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
SEF968Y
PBIB1565E
Continuity should exist.
PBIB1576E

DTC P0139, P0159 HO2S2 EC-293
[VQ35DE]
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Revision: 2006 July 2007 FX35/FX45
DTC P0139, P0159 HO2S2PFP:226A0
Component DescriptionNBS003OV
The heated oxygen sensor 2 (HO2S2), after three way catalyst 1,
monitors the oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air-fuel ratio is controlled to stoichiometric, by the sig-
nal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1V in richer conditions to 0V in leaner condi-
tions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
CONSULT-II Reference Value in Data Monitor ModeNBS003OW
Specification data are reference values.
On Board Diagnosis LogicNBS003OX
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel ratio (A/F) sensor 1. The oxy-
gen storage capacity before the three way catalyst 1 causes the
longer switching time. To judge the malfunctions of heated oxygen
sensor 2, ECM monitors whether the switching response of the sen-
sor's voltage is faster than specified during the various driving condi-
tion such as fuel-cut.
SEF327R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)

Revving engine from idle to 3,000 rpm quickly after the following condi-
tions are met
–Engine: After warming up
–Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no load 0 - 0.3V
←→ Approx. 0.6 -
1.0V
HO2S2 MNTR(B1)
HO2S2 MNTR(B2) LEAN
←→ RICH
SEF302U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0139
0139
(Bank 1)
Heated oxygen sensor
2 circuit slow response It takes more time for the sensor to respond
between rich and lean than the specified time.

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

Heated oxygen sensor 2

Fuel pressure

Fuel injector

Intake air leaks
P0159
0159
(Bank 2)

EC-300
[VQ35DE]
DTC P0139, P0159 HO2S2
Revision: 2006 July 2007 FX35/FX45
2. CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed. Is the 1st trip DTC P0171, P0172, P0174 or P0175 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 OFF.
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 con- nector.
5. Make sure DTC P0102 is displayed.
6. Erase the DTC memory. Refer to EC-66, "
HOW TO ERASE
EMISSION-RELATED DIAGNOSTIC INFORMATION" .
7. Make sure DTC P0000 is displayed.
8. Run engine for at least 10 minutes at idle speed. Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-304, "DTC
P0171, P0174 FUEL INJECTION SYSTEM FUNCTION" or EC-316, "DTC P0172, P0175 FUEL
INJECTION SYSTEM FUNCTION" .
No >> GO TO 3.
3. CHECK HEATED OXYGEN SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between HO2S2 terminal 1 and ECM terminal 78.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
SEF968Y
PBIB1565E
Continuity should exist.
PBIB1576E

EC-304
[VQ35DE]
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 July 2007 FX35/FX45
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis LogicNBS003P4
With the Air-Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the air fuel ratio (A/F) sensor 1. The
ECM calculates the necessary compensation to correct the offset between the actual and the theoretical
ratios.
In case the amount of the compensation value is extremely large (the actual mixture ratio is too lean.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
DTC Confirmation ProcedureNBS003P5
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. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CON- SULT-II.
4. Clear the self-learning control coefficient by touching “CLEAR”.
5. Select “DATA MONITOR” mode with CONSULT-II.
6. Start engine again and let it idle for at least 10 minutes. The 1st trip DTC P0171 or P0174 should be detected at this
stage, if a malfunction exists. If so, go to EC-310, "
Diagnostic
Procedure" .
NOTE:
If 1st trip DTC is not detected during above procedure, perform-
ing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for 10 minutes. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following con-
ditions should be satisfied at the same time.
Sensor Input signal to ECM ECM function Actuator
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
(Mixture ratio feedback signal) Fuel injection
control Fuel injector
DTC No.Trouble diagnosis
name DTC detecting condition Possible cause
P0171
0171
(Bank 1)
Fuel injection system
too lean

Fuel injection system does not operate properly.

The amount of mixture ratio compensation is too
large. (The mixture ratio is too lean.)

Intake air leaks

Air fuel ratio (A/F) sensor 1

Fuel injector

Exhaust gas leaks

Incorrect fuel pressure

Lack of fuel

Mass air flow sensor

Incorrect PCV hose connection
P0174
0174
(Bank 2)
SEF968Y
Engine speed Engine speed in the freeze frame data ± 400 rpm
Vehicle speed Vehicle speed in the freeze frame data ± 10 km/h (6 MPH)

EC-316
[VQ35DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 July 2007 FX35/FX45
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis LogicNBS003P8
With the Air-Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the air fuel ratio (A/F) sensor 1. The
ECM calculates the necessary compensation to correct the offset between the actual and the theoretical
ratios.
In case the amount of the compensation value is extremely large (the actual mixture ratio is too rich.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
DTC Confirmation ProcedureNBS003P9
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. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CON- SULT-II.
4. Clear the self-learning control coefficient by touching “CLEAR”.
5. Select “DATA MONITOR” mode with CONSULT-II.
6. Start engine again and let it idle for at least 10 minutes. The 1st trip DTC P0172, P0175 should be detected at this stage,
if a malfunction exists. If so, go to EC-322, "
Diagnostic Proce-
dure" .
NOTE:
If 1st trip DTC is not detected during above procedure, perform-
ing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for a certain time. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following con-
ditions should be satisfied at the same time.
7. If it is difficult to start engine at step 6, the fuel injection system has a malfunction, too.
Sensor Input signal to ECM ECM function Actuator
Air fuel ration (A/F) sensor 1 Density of oxygen in exhaust gas
(Mixture ratio feedback signal) Fuel injection
control Fuel injector
DTC No.Trouble diagnosis
name DTC detecting condition Possible cause
P0172
0172
(Bank 1) Fuel injection system
too rich

Fuel injection system does not operate properly.

The amount of mixture ratio compensation is too
large. (The mixture ratio is too rich.)

Air fuel ratio (A/F) sensor 1

Fuel injector

Exhaust gas leaks

Incorrect fuel pressure

Mass air flow sensor
P0175
0175
(Bank 2)
SEF968Y
Engine speed Engine speed in the freeze frame data ± 400 rpm
Vehicle speed Vehicle speed in the freeze frame data ± 10 km/h (6 MPH)
Engine coolant temperature
(T) condition When the freeze frame data shows lower than 70
°C (158 °F),
T should be lower than 70 °C (158 °F).
When the freeze frame data shows higher than or equal to 70 °C (158 °F),
T should be higher than or equal to 70 °C (158 °F).

EC-338
[VQ35DE]
DTC P0222, P0223 TP SENSOR
Revision: 2006 July 2007 FX35/FX45
DTC P0222, P0223 TP SENSORPFP:16119
Component DescriptionNBS003PQ
Electric throttle control actuator consists of throttle control motor,
throttle position (TP) sensor, etc. The throttle position sensor
responds to the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.
CONSULT-II Reference Value in Data Monitor ModeNBS003PR
Specification data are reference values.
*: Throttle position sensor 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage signal.
On Board Diagnosis LogicNBS003PS
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
PBIB0145E
MONITOR ITEM CONDITION SPECIFICATION
THRTL SEN 1
THRTL SEN 2*

Ignition switch: ON
(Engine stopped)

Selector lever: D Accelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0222
0222 Throttle position sensor
1 circuit low input An excessively low voltage from the TP sensor
1 is sent to ECM.

Harness or connectors
(TP sensor 1 circuit is open or shorted.)
(APP sensor 2 circuit is shorted.)

Electric throttle control actuator
(TP sensor 1)

Accelerator pedal position sensor.
(APP sensor 2)
P0223
0223 Throttle position sensor
1 circuit high input An excessively high voltage from the TP sen-
sor 1 is sent to ECM.
Engine operation condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10
degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.

DTC P0441 EVAP CONTROL SYSTEM EC-383
[VQ35DE]
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Revision: 2006 July 2007 FX35/FX45
Always perform test at a temperature of 5°C (41 °F) or more.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and let it idle for at least 70 seconds.
4. Select “PURG FLOW P0441” of “EVAPORATIVE SYSTEM” in “DTC CONFIRMATION” mode with CON- SULT-II.
5. Touch “START”. If “COMPLETED” is displayed, go to step 7.
6. When the following conditions are met, “TESTING” will be displayed on the CONSULT-II screen. Maintain the conditions continuously until “TESTING” changes to “COMPLETED”. (It will take at least 35 seconds.)
If “TESTING” is not changed for a long time, retry from step 2.
7. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”. If “NG” is displayed, refer to EC-
384, "Diagnostic Procedure" .
Overall Function CheckNBS003QV
Use this procedure to check the overall monitoring function of the EVAP control system purge flow monitoring.
During this check, a 1st trip DTC might not be confirmed.
WITH GST
1. Lift up drive wheels.
2. Start engine (TCS switch or VDC switch OFF) and warm it up to normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and wait at least 70 seconds.
5. Set voltmeter probes to ECM terminals 32 (EVAP control system pressure sensor signal) and ground.
6. Check EVAP control system pressure sensor value at idle speed and note it.
7. Establish and maintain the following conditions for at least 1 minute.
Selector lever Suitable position
VHCL SPEED SE 32 - 120 km/h (20 - 75 MPH)
ENG SPEED 500 - 3,000 rpm
B/FUEL SCHDL 1.3 - 9.0 msec
COOLAN TEMP/S 70 - 100 °C (158 - 212 °F)
PBIB0826E
Air conditioner switch ON
Headlamp switch ON
Rear window defogger switch ON
Engine speed Approx. 3,000 rpm
Selector lever Any position other than P, N or R
PBIB1109E

EC-384
[VQ35DE]
DTC P0441 EVAP CONTROL SYSTEM
Revision: 2006 July 2007 FX35/FX45
8. Verify that EVAP control system pressure sensor value stays 0.1V less than the value at idle speed (mea-
sured at step 6) for at least 1 second.
9. If NG, go to EC-384, "
Diagnostic Procedure" .
Diagnostic ProcedureNBS003QW
1. CHECK EVAP CANISTER
1. Turn ignition switch OFF.
2. Check EVAP canister for cracks.
OK or NG
OK (With CONSULT-II)>>GO TO 2.
OK (Without CONSULT-II)>>GO TO 3.
NG >> Replace EVAP canister.
2. CHECK PURGE FLOW
With CONSULT-II
1. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP ser- vice port and install vacuum gauge. For the location of EVAP service port, refer to EC-39, "
EVAPORATIVE
EMISSION LINE DRAWING" .
2. Start engine and let it idle.
3. Select “PURG VOL CONT/V” in “ACTIVE TEST” mode with CONSULT-II.
4. Rev engine up to 2,000 rpm.
5. Touch “Qd” and “Qu” on CONSULT-II screen to adjust “PURG VOL CONT/V” opening and check vacuum existence.
OK or NG
OK >> GO TO 7.
NG >> GO TO 4.
3. CHECK PURGE FLOW
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP ser- vice port and install vacuum gauge. For the location of EVAP service port, refer to EC-39, "
EVAPORATIVE
EMISSION LINE DRAWING" .
4. Start engine and let it idle. Do not depress accelerator pedal even slightly.
5. Check vacuum gauge indication before 60 seconds passed after starting engine.
6. Revving engine up to 2,000rpm after 100 seconds passed after starting engine.
OK or NG
OK >> GO TO 7.
NG >> GO TO 4.
PURG VOL CONT/V Vacuum
100% Should exist.
0% Should not exist.
PBIB1678E
Vacuum should not exist.
Vacuum should exist.

DTC P0441 EVAP CONTROL SYSTEM EC-385
[VQ35DE]
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Revision: 2006 July 2007 FX35/FX45
4. CHECK EVAP PURGE LINE
1. Turn ignition switch OFF.
2. Check EVAP purge line for improper connection or disconnection. Refer to EC-39, "
EVAPORATIVE EMISSION LINE DRAWING" .
OK or NG
OK >> GO TO 5.
NG >> Repair it.
5. CHECK EVAP PURGE HOSE AND PURGE PORT
1. Disconnect purge hoses connected to EVAP service port A and
EVAP canister purge volume control solenoid valve B .
2. Blow air into each hose and EVAP purge port C .
3. Check that air flows freely.
OK or NG
OK (With CONSULT-II)>>GO TO 6.
OK (Without CONSULT-II)>>GO TO 7.
NG >> Repair or clean hoses and/or purge port.
6. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
With CONSULT-II
1. Start engine.
2. Perform “PURG VOL CONT/V” in “ACTIVE TEST” mode with CONSULT-II. Check that engine speed varies according to the
valve opening.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Refer to EC-409, "
Component Inspection" .
OK or NG
OK >> GO TO 8.
NG >> Replace EVAP canister purge volume control solenoid valve.
SEF367U
SEF368U
PBIB1678E