power steering INFINITI FX35 2007 Workshop Manual

EC-474
[VQ35DE]
DTC P0550 PSP SENSOR
Revision: 2006 July 2007 FX35/FX45
2. CHECK POWER STEERING PRESSURE (PSP) SENSOR POWER SUPPLY CIRCUIT
1. Disconnect power steering pressure (PSP) sensor harness con- nector.
2. Turn ignition switch ON.
3. Check voltage between PSP sensor terminal 1 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
3. CHECK POWER STEERING PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between PSP sensor terminal 3 and ECM terminal 67. Refer to Wiring Diagram.
4. 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.
4. CHECK POWER STEERING PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 12 and PSP sensor terminal 2. Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
5. CHECK POWER STEERING PRESSURE SENSOR
Refer to EC-475, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace power steering pressure sensor.
PBIB1579E
Voltage: Approximately 5V
PBIB0188E
Continuity should exist.
Continuity should exist.

DTC P0550 PSP SENSOR EC-475
[VQ35DE]
C
D E
F
G H
I
J
K L
M A
EC
Revision: 2006 July 2007 FX35/FX45
6. CHECK INTERMITTENT INCIDENT
Refer to EC-147, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Component InspectionNBS003T4
POWER STEERING PRESSURE SENSOR
1. Reconnect all harness connectors disconnected.
2. Start engine and let it idle.
3. Check voltage between ECM terminal 12 and ground under the following conditions.
Removal and InstallationNBS003T5
POWER STEERING PRESSURE SENSOR
Refer to PS-41, "HYDRAULIC LINE" .
Condition Voltage
Steering wheel: Being turned 0.5 - 4.5V
Steering wheel: Not being turned 0.4 - 0.8V
MBIB0126E

DTC P0643 SENSOR POWER SUPPLY EC-483
[VQ35DE]
C
D E
F
G H
I
J
K L
M A
EC
Revision: 2006 July 2007 FX35/FX45
DTC P0643 SENSOR POWER SUPPLYPFP:18919
On Board Diagnosis LogicNBS003UZ
This self-diagnosis has 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 ProcedureNBS003V0
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 8V 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-486, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble diagnosis
name DTC detecting condition Possible cause
P0643
0643 Sensor power supply
circuit short ECM detects a voltage of power source for
sensor is excessively low or high.

Harness or connectors
(APP sensor 1 circuit is shorted.)
(PSP sensor circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
(EVAP control system pressure sensor circuit
is shorted.)

Accelerator pedal position sensor
(APP sensor 1)

EVAP control system pressure sensor

Power steering pressure sensor

Refrigerant pressure sensor
Engine operation condition in fail-safe mode
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) b y the return
spring.
SEF058Y

DTC P0643 SENSOR POWER SUPPLY EC-485
[VQ35DE]
C
D E
F
G H
I
J
K L
M A
EC
Revision: 2006 July 2007 FX35/FX45
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.
TER-
MINAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
48 LG Sensor power supply
(EVAP control system pres-
sure sensor) [Ignition switch: ON]
Approximately 5V
49 PU Sensor power supply
(Refrigerant pressure sen-
sor) [Ignition switch: ON]
Approximately 5V
68 BR Sensor power supply
(Power steering pressure
sensor) [Ignition switch: ON]
Approximately 5V
82 B/W Sensor ground
(APP sensor 1, ASCD steer-
ing switch, ICC steering
switch) [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 Y/R 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 OR 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

DTC P0643 SENSOR POWER SUPPLY EC-487
[VQ35DE]
C
D E
F
G H
I
J
K L
M A
EC
Revision: 2006 July 2007 FX35/FX45
3. CHECK SENSOR POWER SUPPLY CIRCUITS
Check harness for short to power and short to ground, between the following terminals.
OK or NG
OK >> GO TO 6.
NG >> Repair short to ground or short to power in harness or connectors.
4. CHECK COMPONENTS
Check the following.

Refrigerant pressure sensor (Refer to AT C - 8 9 , "COMPONENT INSPECTION" .)

Power steering pressure sensor (Refer to EC-475, "Component Inspection" .)

EVAP control system pressure sensor (Refer to EC-426, "Component Inspection" .)
OK or NG
OK >> GO TO 9.
NG >> Replace malfunctioning component.
5. CHECK ACCELERATOR PEDAL POSITION SENSOR
Refer to EC-582, "
Component Inspection" .
OK or NG
OK >> GO TO 9.
NG >> GO TO 8.
6. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-83, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-83, "
Throttle Valve Closed Position Learning" .
4. Perform EC-83, "
Idle Air Volume Learning" .
>> INSPECTION END
7. CHECK INTERMITTENT INCIDENT
Refer to EC-147, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
ECM terminal Sensor terminal Reference Wiring Diagram
90 APP sensor terminal 6 EC-578
49 Refrigerant pressure sensor terminal 1EC-664
68 PSP sensor terminal 1EC-472
48 EVAP control system pressure sensor terminal 3EC-429

EC-520
[VQ35DE]
DTC P1564 ICC STEERING SWITCH
Revision: 2006 July 2007 FX35/FX45
3. CHECK ICC STEERING SWITCH GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect combination switch harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between combination switch terminal 15 and ECM terminal 82. Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4. DETECT MALFUNCTIONING PART
Check the following.

Combination switch (spiral cable)

Harness for open and short between ECM and combination switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
5. CHECK ICC STEERING SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 99 and combination switch terminal 14. Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6. DETECT MALFUNCTIONING PART
Check the following.

Combination switch (spiral cable)

Harness for open and short between ECM and combination switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
7. CHECK ICC STEERING SWITCH
Refer to EC-521, "
Component Inspection" .
OK or NG
OK >> GO TO 8.
NG >> Replace ICC steering switch.
8. CHECK INTERMITTENT INCIDENT
Refer to EC-147, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Continuity should exist.
Continuity should exist.

EC-526
[VQ35DE]
DTC P1564 ASCD STEERING SWITCH
Revision: 2006 July 2007 FX35/FX45
2. CHECK ASCD STEERING SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch ON.
2. Select “MAIN SW”, “RESUME/ACC SW”, “SET SW” and “CANCEL SW” in “DATA MONITOR” mode with CONSULT-II.
3. Check each item indication under the following conditions.
Without CONSULT-II
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 99 and ground with press- ing each button.
OK or NG
OK >> GO TO 8.
NG >> GO TO 3.
3. CHECK ASCD STEERING SWITCH GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect combination switch harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between combination switch terminal 15 and ECM terminal 82. Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
Switch Monitor item Condition Indication
MAIN switch MAIN SW Pressed ON
Released OFF
CANCEL switch CANCEL SW Pressed ON
Released OFF
RESUME/ACCELER-
AT E s w i t c h RESUME/ACC SW Pressed ON
Released OFF
SET/COAST switch SET SW Pressed ON
Released OFF
SEC006D
Switch Condition Voltage [V]
MAIN switch Pressed Approx. 0
Released Approx. 4.0
CANCEL switch Pressed Approx. 1.0
Released Approx. 4.0
RESUME/ACCELERATE
switch Pressed Approx. 3.0
Released Approx. 4.0
SET/COAST switch Pressed Approx. 2.0
Released Approx. 4.0
PBIB0311E
Continuity should exist.

DTC P1564 ASCD STEERING SWITCH EC-527
[VQ35DE]
C
D E
F
G H
I
J
K L
M A
EC
Revision: 2006 July 2007 FX35/FX45
4. DETECT MALFUNCTIONING PART
Check the following.

Combination switch (spiral cable)

Harness for open and short between ECM and combination switch
>> Repair open circuit or short to power in harness or connectors.
5. CHECK ASCD STEERING SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 99 and combination switch terminal 14. Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6. DETECT MALFUNCTIONING PART
Check the following.

Combination switch (spiral cable)

Harness for open and short between ECM and combination switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
7. CHECK ASCD STEERING SWITCH
Refer to EC-527, "
Component Inspection" .
OK or NG
OK >> GO TO 8.
NG >> Replace ASCD steering switch.
8. CHECK INTERMITTENT INCIDENT
Refer to EC-147, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Component InspectionNBS003X9
ASCD STEERING SWITCH
1. Disconnect combination switch (spiral cable) harness connector M203.
2. Check continuity between combination switch (spiral cable) ter- minals 14 and 15 with pushing each switch. Continuity should exist.
Switch Condition Resistance [
Ω]
MAIN switch Pressed Approx. 0
Released Approx. 4,000
CANCEL switch Pressed Approx. 250
Released Approx. 4,000
RESUME/ACCELERATE
switch Pressed Approx. 1,480
Released Approx. 4,000
SET/COAST switch Pressed Approx. 660
Released Approx. 4,000
PBIB1621E

EC-692
[VK45DE]
ENGINE CONTROL SYSTEM
Revision: 2006 July 2007 FX35/FX45
Multiport Fuel Injection (MFI) SystemNBS004JO
INPUT/OUTPUT SIGNAL CHART
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from the crankshaft position sensor (POS), camshaft position
sensor (PHASE) and the mass air flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.


During warm-up

When starting the engine

During acceleration

Hot-engine operation

When selector lever is changed from N to D

High-load, high-speed operation


During deceleration

During high engine speed operation
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
3
Piston position
Fuel injection
& mixture ratio
control Fuel injector
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Battery Battery voltage*
3
Knock sensor Engine knocking condition
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit) VDC/TCS operation command*
2
Air conditioner switch Air conditioner operation
Wheel sensor Vehicle speed*
2

EC-696
[VK45DE]
AIR CONDITIONING CUT CONTROL
Revision: 2006 July 2007 FX35/FX45
AIR CONDITIONING CUT CONTROLPFP:23710
Input/Output Signal ChartNBS00415
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
System DescriptionNBS00416
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.

When the accelerator pedal is fully depressed.

When cranking the engine.

At high engine speeds.

When the engine coolant temperature becomes excessively high.

When operating power steering during low engine speed or low vehicle speed.

When engine speed is excessively low.

When refrigerant pressure is excessively low or high.
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch Air conditioner ON signal*
1
Air conditioner
cut control Air conditioner relay
Accelerator pedal position sensor Accelerator pedal position
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
2
Engine coolant temperature sensor Engine coolant temperature
Battery Battery voltage*
2
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensor Vehicle speed*
1