2005 INFINITI FX35 engine

DTC P1574 ICC VEHICLE SPEED SENSOR EC-605
[VQ35DE]
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Revision: 2005 July 2005 FX
DTC P1574 ICC VEHICLE SPEED SENSORPFP:31036
Component DescriptionABS007ZD
The ECM receives two vehicle speed signals via CAN communication line. One is sent from “unified meter and
A/C amp.”, and the other is from TCM (Transmission control module). The ECM uses these signals for ICC
control. Refer to ACS-6, "
DESCRIPTION" for ICC functions.
On Board Diagnosis LogicABS007ZE

This self-diagnosis has the one trip detection logic.

The MIL will not light up for this self-diagnosis.
NOTE:

If DTC P1574 is displayed with DTC U1000, U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-171
.

If DTC P1574 is displayed with DTC P0500, first perform the trouble diagnosis for DTC P0500.
Refer to EC-391
.

If DTC P1574 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-402
.
DTC Confirmation ProcedureABS007ZF
CAUTION:
Always drive vehicle at a safe speed.
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:
Step 3 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. Start engine.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Drive the vehicle at more than 40 km/h (25MPH).
4. If DTC is detected, go to EC-606, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble Diagnosis
Name DTC Detecting Condition Possible Cause
P1574
1574 ICC vehicle speed
sensor ECM detects a difference between two vehicle
speed signals is out of the specified range.

Harness or connectors
(The CAN communication line is open or
shorted.)

Unified meter and A/C amp.

ABS actuator and electric unit (control unit)

Wheel sensor

TCM

ECM
SEF058Y

DTC P1574 ASCD VEHICLE SPEED SENSOR EC-607
[VQ35DE]
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Revision: 2005 July 2005 FX
DTC P1574 ASCD VEHICLE SPEED SENSORPFP:31036
Component DescriptionABS006WQ
The ECM receives two vehicle speed signals via CAN communication line. One is sent from “unified meter and
A/C amp.”, and the other is from TCM (Transmission control module). The ECM uses these signals for ASCD
control. Refer to EC-36, "
AUTOMATIC SPEED CONTROL DEVICE (ASCD)" for ASCD functions.
On Board Diagnosis LogicABS006WR
This self-diagnosis has the one trip detection logic.
The MIL will not light up for this diagnosis.
NOTE:

If DTC P1574 is displayed with DTC U1000, U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-171
.

If DTC P1574 is displayed with DTC P0500, first perform the trouble diagnosis for DTC P0500.
Refer to EC-391

If DTC P1574 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-402
DTC Confirmation ProcedureABS006WS
CAUTION:
Always drive vehicle at a safe speed.
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:
Step 3 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. Start engine.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Drive the vehicle at more than 40 km/h (25 MPH).
4. If DTC is detected, go to EC-608, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble Diagnosis
Name DTC Detecting Condition Possible Cause
P1574
1574 ASCD vehicle speed
sensor ECM detects a difference between two vehicle
speed signals is out of the specified range.

Harness or connectors
(The CAN communication line is open or
shorted.)

Unified meter and A/C amp.

ABS actuator and electric unit (control unit)

Wheel sensor

TCM

ECM
SEF058Y

DTC P1706 PNP SWITCH EC-609
[VQ35DE]
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Revision: 2005 July 2005 FX
DTC P1706 PNP SWITCHPFP:32006
Component DescriptionABS006WU
When the gear position is P or N, park/neutral position (PNP) switch is ON.
ECM detects the position because the continuity of the line (the ON signal) exists.
CONSULT-II Reference Value in Data Monitor ModeABS006WV
Specification data are reference values.
On Board Diagnosis LogicABS006WW
DTC Confirmation ProcedureABS006WX
CAUTION:
Always drive vehicle at a safe speed.
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 “P/N POSI SW” in “DATA MONITOR” mode with CON- SULT-II. Then check the “P/N POSI SW” signal under the follow-
ing conditions.
If NG, go to EC-612, "
Diagnostic Procedure" .
If OK, go to following step.
3. Select “DATA MONITOR” mode with CONSULT-II.
4. Start engine and warm it up to normal operating temperature.
5. Maintain the following conditions for at least 60 consecutive sec- onds.
6. If 1st trip DTC is detected, go to EC-612, "
Diagnostic Procedure"
.
Overall Function CheckABS006WY
Use this procedure to check the overall function of the park/neutral position (PNP) switch circuit. During this
check, a 1st trip DTC might not be confirmed.
MONITOR ITEM CONDITION SPECIFICATION
P/N POSI SW

Ignition switch: ON Selector lever: P or N ON
Selector lever: Except above OFF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1706
1706 Park/neutral position
switch The signal of the park/neutral position (PNP)
switch is not changed in the process of engine
starting and driving.

Harness or connectors
[The park/neutral position (PNP) switch
circuit is open or shorted.]

Park/neutral position (PNP) switch

Unified meter and A/C amp.
Position (Selector lever) Known-good signal
P or N position ON
Except above position OFF
ENG SPEED 1,000 - 6,375 rpm
COOLAN TEMP/S More than 70 °C (158 °F)
B/FUEL SCHDL 2.0 - 31.8 msec
VHCL SPEED SE More than 64 km/h (40 MPH)
Selector lever Suitable position
SEF212Y
SEF213Y

EC-614
[VQ35DE]
DTC P1805 BRAKE SWITCH
Revision: 2005 July 2005 FX
DTC P1805 BRAKE SWITCHPFP:25320
DescriptionABS006X1
Brake switch signal is applied to the ECM through the stop lamp switch when the brake pedal is depressed.
This signal is used mainly to decrease the engine speed when the vehicle is driving.
CONSULT-II Reference Value in Data Monitor ModeABS006X2
Specification data are reference values.
On Board Diagnosis LogicABS006X3
The MIL will not light up for this diagnosis.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode.
DTC Confirmation ProcedureABS006X4
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. Fully depress the brake pedal for at least 5 seconds.
3. Erase the DTC with CONSULT-II.
4. Select “DATA MONITOR” mode with CONSULT-II.
5. If 1st trip DTC is detected, go to EC-616, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
MONITOR ITEM CONDITION SPECIFICATION
BRAKE SW

Ignition switch: ON Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1805
1805 Brake switch A brake switch signal is not sent to ECM for
extremely long time while the vehicle is driving.

Harness or connectors
(Stop lamp switch circuit is open or
shorted.)

Stop lamp switch
Engine operating condition in fail-safe mode
ECM controls the electric throttle control actuator by regulating the throttle opening to a small range.
Therefore, acceleration will be poor.
Vehicle condition Driving condition
When engine is idling Normal When accelerating Poor acceleration
SEF058Y

DTC P2122, P2123 APP SENSOR EC-619
[VQ35DE]
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Revision: 2005 July 2005 FX
DTC P2122, P2123 APP SENSORPFP:18002
Component DescriptionABS006X8
The accelerator pedal position sensor is installed on the upper end
of the accelerator pedal assembly. The sensor detects the accelera-
tor 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 ModeABS006X9
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 LogicABS006XA
These self-diagnoses have the one trip detection logic.
NOTE:
If DTC P2122 or P2123 is displayed with DTC P1229, first perform the trouble diagnosis for DTC P1229.
Refer to EC-483, "
DTC P1229 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 SEN1

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.8V
ACCEL SEN2*

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
(The APP sensor 1 circuit is open or
shorted.)

Accelerator pedal position sensor
(Accelerator pedal position 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.

EC-620
[VQ35DE]
DTC P2122, P2123 APP SENSOR
Revision: 2005 July 2005 FX
DTC Confirmation ProcedureABS006XB
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:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If DTC is detected, go to EC-622, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
SEF058Y

EC-622
[VQ35DE]
DTC P2122, P2123 APP SENSOR
Revision: 2005 July 2005 FX
Specification 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.
Diagnostic ProcedureABS006XD
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground three screws on the body. Refer to EC-170, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
82 B/W Sensor ground
(APP sensor 1) [Engine is running]

Warm-up condition

Idle speed
Approximately 0V
83 G/OR Sensor ground
(APP sensor 2) [Engine is running]

Warm-up condition

Idle speed
Approximately 0V
90 L/B Sensor power supply
(APP sensor 1) [Ignition switch: ON]
Approximately 5V
91 G Sensor power supply
(APP sensor 2) [Ignition switch: ON]
Approximately 5V
98 B/P Accelerator pedal position
sensor 2 [Ignition switch: ON]

Engine stopped

Accelerator pedal: Fully released
0.15 - 0.60V
[Ignition switch: ON]

Engine stopped

Accelerator pedal: Fully depressed 1.95 - 2.40V
106 R/B Accelerator pedal position
sensor 1 [Ignition switch: ON]

Engine stopped

Accelerator pedal: Fully released
0.5 - 1.0V
[Ignition switch: ON]

Engine stopped

Accelerator pedal: Fully depressed 3.9 - 4.7V
PBIB2625E

EC-626
[VQ35DE]
DTC P2127, P2128 APP SENSOR
Revision: 2005 July 2005 FX
DTC P2127, P2128 APP SENSORPFP:18002
Component DescriptionABS006XG
The accelerator pedal position sensor is installed on the upper end
of the accelerator pedal assembly. The sensor detects the accelera-
tor 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 ModeABS006XH
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 LogicABS006XI
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 SEN1

Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.8V
ACCEL SEN2*

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

Accelerator pedal position sensor
(Accelerator pedal position 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.