2007 INFINITI FX35 fuel

DTC P1421 COLD START CONTROL EC-513
[VQ35DE]
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Revision: 2006 July 2007 FX35/FX45
DTC P1421 COLD START CONTROLPFP:23710
DescriptionNBS006S9
ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way catalyst by heating the catalyst and reduces emissions.
On Board Diagnosis LogicNBS006SA
DTC Confirmation ProcedureNBS006SB
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.

If DTC P1421 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-II
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-II.
4. Check that the “COOLAN TEMP/S” indication is between 4 °C
(39 °F) and 36 °C (97 °F).
If “COOLAN TEMP/S” indication is within the specified value, go
to the following step.
If “COOLANT TEMP/S” indication is out of the specified value,
cool engine down or warm engine up and go to step 1.
5. Start engine and let it idle for 5 minutes.
6. If 1st trip DTC is detected, go to EC-513, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureNBS006SC
1. PERFORM IDLE AIR VOLUME LEARNING
Perform EC-83, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Ye s > > G O T O 2 .
No >> Follow the instruction of Idle Air Volume Learning.
2. CHECK INTAKE SYSTEM
Check for the cause of intake air volume lacking. Refer to the following.

Crushed intake air passage

Intake air passage clogging
OK or NG
OK >> GO TO 3.
NG >> Repair or replace malfunctioning part
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421
1421 Cold start emission reduction
strategy monitoring ECM does not control ignition timing and engine
idle speed properly when engine is started with
prewarming up condition.

Lack of intake air volume

Fuel injection system

ECM
SEF174Y

EC-514
[VQ35DE]
DTC P1421 COLD START CONTROL
Revision: 2006 July 2007 FX35/FX45
3. CHECK FUEL INJECTION SYSTEM FUNCTION
Perform EC-304, "
DTC Confirmation Procedure" in DTC P0171, P0174 FUEL INJECTION SYSTEM FUNC-
TION.
OK or NG
OK >> GO TO 4.
NG >> Go to EC-310, "
Diagnostic Procedure" .
4. PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT-II
1. Turn ignition switch ON.
2. Select “SELF DIAG RESULTS” mode with CONSULT-II.
3. Touch “ERASE”.
4. Perform DTC Confirmation Procedure.
See EC-513, "
DTC Confirmation Procedure" .
5. Is the 1st trip DTC P1421 displayed again?
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-513, "
DTC Confirmation Procedure" .
4. Is the 1st trip DTC P1421 displayed again?
Ye s o r N o
Yes >> GO TO 5.
No >> INSPECTION END
5. REPLACE ECM
1. Replace ECM.
2. Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to BL-207, "
ECM Re-Communicating Function" .
3. Perform EC-82, "
VIN Registration" .
4. Perform EC-83, "
Accelerator Pedal Released Position Learning" .
5. Perform EC-83, "
Throttle Valve Closed Position Learning" .
6. Perform EC-83, "
Idle Air Volume Learning" .
>> INSPECTION END

EC-574
[VQ35DE]
DTC P2119 ELECTRIC THROTTLE CONTROL ACTUATOR
Revision: 2006 July 2007 FX35/FX45
DTC P2119 ELECTRIC THROTTLE CONTROL ACTUATORPFP:16119
Component DescriptionNBS003TV
Electric throttle control actuator consists of throttle control motor, throttle position sensor, etc.
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The throttle position sensor detects the throttle valve position, and the opening and closing speed of the throt-
tle valve and feeds 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.
On Board Diagnosis LogicNBS003TW
This self-diagnosis has the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureNBS003TX
NOTE:

Perform PROCEDURE FOR MALFUNCTION A AND B first. If the DTC cannot be confirmed, perform
PROCEDURE FOR MALFUNCTION C.

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 AND B
With CONSULT-II
1. Turn ignition switch ON and wait at least 1 second.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Shift selector lever to D position and wait at least 3 seconds.
4. Shift selector lever to P, N position.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Turn ignition switch ON and wait at least 1 second.
7. Shift selector lever to D position and wait at least 3 seconds.
8. Shift selector lever to P, N position.
9. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
10. If DTC is detected, go to EC-575, "
Diagnostic Procedure" .
With GST
Follow the procedure “With CONSULT-II” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2119
2119 Electric throttle control
actuator A)
Electric throttle control actuator does not func-
tion properly due to the return spring malfunc-
tion.

Electric throttle control actuator
B) Throttle valve opening angle in fail-safe mode is
not in specified range.
C) ECM detect the throttle valve is stuck open.
Detected items Engine operating condition in fail-safe mode
Malfunction A The ECM controls the electric throttle actuator by regulating the throttle opening around the idle position.
The engine speed will not rise more than 2,000 rpm.
Malfunction B ECM controls the electric throttle control actuator by regulating the throttle opening to 20 degrees or less.
Malfunction C While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops, the engine stalls.
The engine can restart in N or P position, and engine speed will not exceed 1,000 rpm or more.
SEF058Y

EC-576
[VQ35DE]
DTC P2122, P2123 APP SENSOR
Revision: 2006 July 2007 FX35/FX45
DTC P2122, P2123 APP SENSORPFP:18002
Component DescriptionNBS003YD
The accelerator pedal position (APP) sensor is installed on the upper
end of the accelerator pedal assembly. The sensor detects the
accelerator position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-II Reference Value in Data Monitor ModeNBS003YE
Specification data are reference values.
*: Accelerator pedal position sensor 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage.
On Board Diagnosis LogicNBS003YF
These self-diagnoses have the one trip detection logic.
NOTE:
If DTC P2122 or P2123 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-483, "
DTC P0643 SENSOR POWER SUPPLY" .
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
PBIB1741E
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SEN 1

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.8V
ACCEL SEN 2*

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.3 - 1.2V
Accelerator pedal: Fully depressed 3.9 - 4.8V
CLSD THL POS

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2122
2122 Accelerator pedal posi-
tion sensor 1 circuit low
input An excessively low voltage from the APP sen-
sor 1 is sent to ECM.

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

Accelerator pedal position sensor
(APP sensor 1)
P2123
2123 Accelerator pedal posi-
tion sensor 1 circuit high
input An excessively high voltage from the APP sen-
sor 1 is sent to ECM.
Engine operating 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 P2127, P2128 APP SENSOR EC-583
[VQ35DE]
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Revision: 2006 July 2007 FX35/FX45
DTC P2127, P2128 APP SENSORPFP:18002
Component DescriptionNBS003YL
The accelerator pedal position (APP) sensor is installed on the upper
end of the accelerator pedal assembly. The sensor detects the
accelerator position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-II Reference Value in Data Monitor ModeNBS003YM
Specification data are reference values.
*: Accelerator pedal position sensor 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage.
On Board Diagnosis LogicNBS003YN
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.
PBIB1741E
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SEN 1

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.8V
ACCEL SEN 2*

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.3 - 1.2V
Accelerator pedal: Fully depressed 3.9 - 4.8V
CLSD THL POS

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2127
2127 Accelerator pedal posi-
tion sensor 2 circuit low
input An excessively low voltage from the APP sen-
sor 2 is sent to ECM.

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

Accelerator pedal position sensor
(APP sensor 2)

Electric throttle control actuator
(TP sensor 1 and 2)
P2128
2128 Accelerator pedal posi-
tion sensor 2 circuit high
input An excessively high voltage from the APP sen-
sor 2 is sent to ECM.
Engine operating 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 P2138 APP SENSOR EC-597
[VQ35DE]
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Revision: 2006 July 2007 FX35/FX45
DTC P2138 APP SENSORPFP:18002
Component DescriptionNBS003Z1
The accelerator pedal position (APP) sensor is installed on the upper
end of the accelerator pedal assembly. The sensor detects the
accelerator position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometers which transform the accelerator pedal
position into output voltage, and emit the voltage signal to the ECM.
In addition, these sensors detect the opening and closing speed of
the accelerator pedal and feed the voltage signals to the ECM. The
ECM judges the current opening angle of the accelerator pedal from
these signals and controls the throttle control motor based on these
signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-II Reference Value in Data Monitor ModeNBS003Z2
Specification data are reference values.
*: Accelerator pedal position sensor 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage.
On Board Diagnosis LogicNBS003Z3
This self-diagnosis has the one trip detection logic.
NOTE:
If DTC P2138 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-483, "
DTC P0643 SENSOR POWER SUPPLY" .
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
PBIB1741E
MONITOR ITEM CONDITION SPECIFICATION
ACCEL SEN 1

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.8V
ACCEL SEN 2*

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.3 - 1.2V
Accelerator pedal: Fully depressed 3.9 - 4.8V
CLSD THL POS

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2138
2138 Accelerator pedal posi-
tion sensor circuit
range/performance Rationally incorrect voltage is sent to ECM
compared with the signals from APP sensor 1
and APP sensor 2.

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

Accelerator pedal position sensor
(APP sensor 1 and 2)

Electric throttle control actuator
(TP sensor 1 and 2)
Engine operating 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 P2A00, P2A03 A/F SENSOR 1 EC-605
[VQ35DE]
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Revision: 2006 July 2007 FX35/FX45
DTC P2A00, P2A03 A/F SENSOR 1PFP:22693
Component DescriptionNBS003VH
The air fuel ratio (A/F) sensor is a planar dual-cell limit current sen-
sor. The sensor element of the air fuel ratio (A/F) sensor is the com-
bination of a Nernst concentration cell (sensor cell) with an oxygen-
pump cell, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range (0.7 < < air).
The exhaust gas components diffuse through the diffusion gap at the
electrode of the oxygen pump and Nernst concentration cell, where
they are brought to thermodynamic balance.
An electronic circuit controls the pump current through the oxygen-
pump cell so that the composition of the exhaust gas in the diffusion
gap remains constant at = 1. Therefore, the air fuel ratio (A/F) sen-
sor is able to indicate air/fuel ratio by this pumping of current. In
addition, a heater is integrated in the sensor to ensure the required
operating temperature of 700 - 800 °C (1,292 - 1,472 °F).
CONSULT-II Reference Value in Data Monitor ModeNBS003VI
Specification data are reference values.
On Board Diagnosis LogicNBS003VJ
To judge the malfunction, the A/F signal computed by ECM from the air fuel ratio (A/F) sensor 1 signal is mon-
itored not to be shifted to LEAN side or RICH side.
SEF579Z
SEF580Z
MONITOR ITEM CONDITION SPECIFICATION
A/F SEN1 (B1)
A/F SEN1 (B2)

Engine: After warming up Maintaining engine speed at
2,000 rpm Fluctuates around 1.5V
DTC No. Trouble diagnosis name DTC detecting condition Possible Cause
P2A00
2A00
(Bank 1) Air fuel ratio (A/F) sensor 1
lean shift monitoring

The output voltage computed by ECM from the
air fuel ratio (A/F) sensor 1 signal is shifted to
the lean side for a specified period.

The A/F signal computed by ECM from the air
fuel ratio (A/F) sensor 1 signal is shifted to the
rich side for a specified period.

Air fuel ratio (A/F) sensor 1

Air fuel ratio (A/F) sensor 1 heater

Fuel pressure

Fuel injector

Intake air leaks
P2A03
2A03
(Bank 2)

DTC P2A00, P2A03 A/F SENSOR 1 EC-611
[VQ35DE]
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Revision: 2006 July 2007 FX35/FX45
2. RETIGHTEN AIR FUEL RATIO (A/F) SENSOR 1
Loosen and retighten the air fuel ratio (A/F) sensor 1.
>> GO TO 3.
3. CHECK FOR INTAKE AIR LEAK
1. Start engine and run it at idle.
2. Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace. Tightening torque: 40 - 60 N-m (4.1 - 6.1 kg-m, 30 - 44 ft-lb)
PBIB2200E