fuel INFINITI FX35 2008 Service Manual

EC-506
< SERVICE INFORMATION >[VQ35DE]
DTC P2122, P2123 APP SENSOR
DTC P2122, P2123 APP SENSOR
Component DescriptionINFOID:0000000001326387
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 accelerato
r pedal is determined by the ECM
receiving the signal from the accelerator pedal positi on sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326388
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 Diagn osis LogicINFOID:0000000001326389
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-424
.
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 vo
ltage 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 vo
ltage 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.
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-512
< SERVICE INFORMATION >[VQ35DE]
DTC P2127, P2128 APP SENSOR
DTC P2127, P2128 APP SENSOR
Component DescriptionINFOID:0000000001326395
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 accelerato
r pedal is determined by the ECM
receiving the signal from the accelerator pedal positi on sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326396
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 Diagn osis LogicINFOID:0000000001326397
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.
DTC Confirmation ProcedureINFOID:0000000001326398
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
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 vo
ltage 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 vo
ltage 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.
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-524
< SERVICE INFORMATION >[VQ35DE]
DTC P2138 APP SENSOR
DTC P2138 APP SENSOR
Component DescriptionINFOID:0000000001326411
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 accelerato
r pedal is determined by the ECM
receiving the signal from the accelerator pedal positi on sensor. The ECM uses this signal for the engine oper-
ation such as fuel cut.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326412
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 Diagn osis LogicINFOID:0000000001326413
This self-diagnosis has the one trip detection logic.
NOTE:
If DTC P2138 is displayed with DTC P0643, firs t perform the trouble diagnosis for DTC P0643.
Refer to EC-424
.
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 sign
als 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.
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-532
< SERVICE INFORMATION >[VQ35DE]
DTC P2A00, P2A03 A/F SENSOR 1
DTC P2A00, P2A03 A/F SENSOR 1
Component DescriptionINFOID:0000000001326419
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 concentrati on 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-III Reference Value in Data Monitor ModeINFOID:0000000001326420
Specification data are reference values.
On Board Diagn osis LogicINFOID:0000000001326421
To judge the malfunction, the A/F signal computed by ECM fr om the air fuel ratio (A/F) sensor 1 signal is mon-
itored not to be shifted to LEAN side or RICH side.
DTC Confirmation ProcedureINFOID:0000000001326422
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
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)
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

DTC P2A00, P2A03 A/F SENSOR 1EC-537
< SERVICE INFORMATION > [VQ35DE]
C
D
E
F
G H
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K L
M A
EC
NP
O
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis ProcedureINFOID:0000000001326424
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-144, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
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.
TERMI- NAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
24 L A/F sensor 1 heater
(bank 2) [Engine is running]

Warm-up condition
 Idle speed Approximately 5V
57 G A/F sensor 1 (bank 2) [Engine is running]

Warm-up condition
 Idle speed Approximately 2.6V
58 Y Approximately 2.3V
76 P Approximately 3.1V
77 BR Approximately 2.3V
PBIB1584E
PBIB2625E
Tightening torque: 40 - 60 N-m (4.1 - 6.1 kg-m, 30 - 44 ft-lb)
PBIB2200E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-538
< SERVICE INFORMATION >[VQ35DE]
DTC P2A00, P2A03 A/F SENSOR 1
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4.CLEAR THE SELF-LEARNING DATA
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-III.
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-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con-
nector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-55, "
Emission-Related
Diagnostic Information".
8. Make sure DTC P0000 is displayed.
9. 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-274 or EC-284.
No >> GO TO 5.
5.CHECK HARNESS CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
3. Check harness connector for water. Water should not exit.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace harness connector.
6.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
PBIB1565E
PBIB2200E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

DTC P2A00, P2A03 A/F SENSOR 1EC-539
< SERVICE INFORMATION > [VQ35DE]
C
D
E
F
G H
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K L
M A
EC
NP
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1. Disconnect air fuel ratio (A
/F) sensor 1 harness connector.
2. Turn ignition switch ON.
3. Check voltage between air fuel ratio (A/F) sensor 1 terminal 3 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E64, F65
 IPDM E/R harness connector E7
 10A fuse
 Harness for open or short between air fuel ratio (A/F) sensor 1 and fuse
>> Repair or replace harness or connectors.
8.CHECK AIR FUEL RATIO (A/F) SENSOR 1 INPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between the following terminals. Refer to Wiring Diagram.
4. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.Voltage: Battery voltage
PBIB2190E
PBIB1683E
A/F sensor 1 terminal ECM terminal
Bank1 116
275
535
656
Bank 2 176
277
557
658
Continuity should exist.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-540
< SERVICE INFORMATION >[VQ35DE]
DTC P2A00, P2A03 A/F SENSOR 1
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK AIR FUEL RATIO (A/F) SENSOR 1 HEATER
Refer to EC-158, "
Component Inspection".
OK or NG
OK >> GO TO 10.
NG >> GO TO 11.
10.CHECK INTERMITTENT INCIDENT
Perform EC-139
.
OK or NG
OK >> GO TO 11.
NG >> Repair or replace.
11 .REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
 Discard any air fuel ratio (A/F) sensor which has b een 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.
 Before installing new air fuel ratio (A/F) sensor, clean exhaust system threads using Heated Oxygen
Sensor Thread Cleaner tool J-43897-18 or J- 43897-12 and approved anti-seize lubricant.
>> GO TO 12.
12.CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch ON.
2. Select “A/F ADJ-B1” and “A/F ADJ-B2” in “DATA MONITOR” mode with CONSULT-III.
3. Make sure that “0.000” is displayed on CONSULT-III screen.
OK or NG
OK >> INSPECTION END
NG >> GO TO 13.
13.CLEAR THE SELF-LEARNING DATA.
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-III.
3. Clear the self-learning control coefficient by touching “CLEAR”.
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
116176
275277
535557
656658
Continuity should not exist.
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

DTC P2A00, P2A03 A/F SENSOR 1EC-541
< SERVICE INFORMATION > [VQ35DE]
C
D
E
F
G H
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K L
M A
EC
NP
O
3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con-
nector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-55, "
Emission-Related
Diagnostic Information".
8. Make sure DTC P0000 is displayed.
>> GO TO 14.
14.CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch OFF and then ON.
2. Select “A/F ADJ-B1” and “A/F ADJ-B2” in “DATA MONITOR” mode with CONSULT-III.
3. Make sure that “0.000” is displayed on CONSULT-III screen.
>>INSPECTION END
Removal and InstallationINFOID:0000000001326425
AIR FUEL RATIO (A/F) SENSOR 1
Refer to EM-26.
PBIB1565E
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

EC-552
< SERVICE INFORMATION >[VQ35DE]
FUEL INJECTOR
FUEL INJECTOR
Component DescriptionINFOID:0000000001326438
The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the fuel injector circuit, the coil in the fuel injec-
tor is energized. The energized coil pulls the Ball valve back and
allows fuel to flow through the fuel injector into the intake manifold.
The amount of fuel injected depends upon the fuel injection pulse
duration. Pulse duration is the length of time the fuel injector remains
open. The ECM controls the injection pulse duration based on
engine fuel needs.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326439
Specification data are reference values.
SEF375Z
MONITOR ITEM CONDITION SPECIFICATION
B/FUEL SCHDL See EC-131
.
INJ PULSE-B1
INJ PULSE-B2  Engine: After warming up
 Selector lever: P or N
 Air conditioner switch: OFF
No load Idle 2.0 - 3.0 msec
2,000 rpm 1.9 - 2.9 msec
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
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