Power steering system INFINITI FX35 2004 Workshop Manual

ENGINE CONTROL SYSTEM
EC-683
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
Air Conditioning Cut ControlABS00BZ9
INPUT/OUTPUT SIGNAL CHART
*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 DESCRIPTION
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.
Fuel Cut Control (at No Load and High Engine Speed)ABS00BZA
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
If the engine speed is above 1,400 rpm under no load (for example, the shift position is neutral and engine
speed is over 1,400 rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies
based on engine speed.
Fuel cut will be operated until the engine speed reaches 1,000 rpm, then fuel cut will be cancelled.
NOTE:
This function is different from deceleration control listed under Multiport Fuel Injection (MFI) System, EC-679
.
Sensor Input signal to ECM ECM function Actuator
Air conditioner switch*
1Air conditioner ON signal
Air conditioner
cut controlAir conditioner relay Throttle position sensor Throttle position
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*
1Vehicle speed
Sensor Input signal to ECM ECM function Actuator
Park/neutral position (PNP) switch Neutral position
Fuel cut control Fuel injector Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
Wheel sensor* Vehicle speed

TROUBLE DIAGNOSIS
EC-731
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
Fail-safe ChartABS00BZQ
When the DTC listed below is detected, the ECM enters fail-safe mode and the MIL lights up.
2
P0031P0032 P0051 P0052 Heated oxygen sensor 1 heater

P0037 P0038 P0057 P0058 Heated oxygen sensor 2 heater

P0132 P0133 P0134 P0152 P0153 P0154 P1143 P1144 P1163 P1164 Heated oxygen sensor 1

P0138 P0139 P0158 P0159 P1146 P1147 P1166 P1167 Heated oxygen sensor 2

P0441 EVAP control system purge flow monitoring

P0444 P0445 P1444 EVAP canister purge volume control solenoid valve

P0447 P1446 EVAP canister vent control valve

P0451 P0452 P0453 EVAP control system pressure sensor

P0550 Power steering pressure sensor

P0710 P0720 P0740 P0744 P0745 P1716 P1720 P1730 P1752 P1754 P1757 P1759 P1762 P1764 P1767 P1769
P1772 P1774 A/T related sensors, solenoid valves and switches

P1065 ECM power supply

P 1111 P 1136 Intake valve timing control solenoid valve

P1122 Electric throttle control function

P1124 P1126 P1128 Electric throttle control actuator

P1140 P1145 Intake valve timing control position sensor

P1217 Engine over temperature (OVERHEAT)

P1805 Brake switch
3

P0011 P0021 Intake valve timing control

P0171 P0172 P0174 P0175 Fuel injection system function

P0300 - P0308 Misfire

P0420 P0430 Three way catalyst function

P0442 P0456 EVAP control system (SMALL LEAK, VERY SMALL LEAK)

P0455 EVAP control system (GROSS LEAK)

P0506 P0507 Idle speed control system

P1121 Electric throttle control actuator

P1148 P1168 Closed loop control

P1211 TCS control unit

P1212 TCS communication line

P1564 ICC steering switch/ASCD steering switch

P1568 ICC command value

P1572 ICC brake switch/ASCD brake switch

P1574 ICC vehicle speed sensor/ASCD vehicle speed sensor

P1780 Shift change signal Priority Detected items (DTC)
DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103
P1102Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.

EC-756
[VK45DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
50 W Throttle position sensor 1[Ignition switch: ON]

Engine stopped

Shift lever position is D

Accelerator pedal is fully releasedMore than 0.36V
[Ignition switch: ON]

Engine stopped

Shift lever position is D

Accelerator pedal is fully depressedLess than 4.75V
51 L/W Mass air flow sensor[Engine is running]

Warm-up condition

Idle speed1.2 - 1.8V
[Engine is running]

Warm-up condition

Engine speed is 2,500 rpm1.7 - 2.4V
53 R/LIntake valve timing control
position sensor (bank 2)[Engine is running]

Warm-up condition

Idle speed0 - 1.0V
[Engine is running]

Engine speed is 2,000 rpm0 - 1.0V
55 W/RHeated oxygen sensor 2
(bank 1)[Engine is running]

Warm-up condition

Revving engine from idle to 3,000 rpm
quickly after the following conditions are met
–After keeping the engine speed between
3,500 and 4,000 rpm for 1 minute and at idle
for 1 minute under no load0 - Approximately 1.0V
66 BSensor ground
(Throttle position sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
67 B/WSensor ground
(Mass air flow sensor / IAT
sensor / Power steering
pressure sensor / EVAP
control system pressure
sensor / Refrigerant pres-
sure sensor / ECT sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
68 SBSensor power supply
(Power steering pressure
sensor)[Ignition switch: ON]Approximately 5V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB2046E

EC-758
[VK45DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
91 GSensor power supply
(APP sensor 2)[Ignition switch: ON]Approximately 5V
94 L CAN communication line[Ignition switch: ON]Approximately 2.6 - 3.2V
Output voltage varies with the
communication status.
98 B/PAccelerator pedal position
sensor 2[Ignition switch: ON]

Engine stopped

Accelerator pedal is fully released0.15 - 0.60V
[Ignition switch: ON]

Engine stopped

Accelerator pedal is fully depressed1.95 - 2.40V
99 G/YICC steering switch
(models with ICC system)[Ignition switch: ON]

ICC steering switch: OFFApproximately 4.3V
[Ignition switch: ON]

ON/OFF (MAIN) switch: PressedApproximately 0V
[Ignition switch: ON]

CANCEL switch: PressedApproximately 1.3V
[Ignition switch: ON]

DISTANCE switch: PressedApproximately 2.2V
[Ignition switch: ON]

COAST/SET switch: PressedApproximately 3V
[Ignition switch: ON]

ACCEL/RESUME switch: PressedApproximately 3.7V
99 G/YASCD steering switch
(models with ASCD system)[Ignition switch: ON]

ASCD steering switch: OFFApproximately 4V
[Ignition switch: ON]

ON/OFF (MAIN) switch: PressedApproximately 0V
[Ignition switch: ON]

CANCEL switch: PressedApproximately 1V
[Ignition switch: ON]

COAST/SET switch: PressedApproximately 2V
[Ignition switch: ON]

ACCEL/RESUME switch: PressedApproximately 3V
101 P/L Stop lamp switch[Ignition switch: OFF]

Brake pedal is fully releasedApproximately 0V
[Ignition switch: OFF]

Brake pedal is depressedBATTERY VOLTAGE
(11 - 14V)
102 LG/B PNP switch[Ignition switch: ON]

Shift lever position is P or NApproximately 0V
[Ignition switch: ON]

Except above positionBATTERY VOLTAGE
(11 - 14V)
104 L/OR Throttle control motor relay[Ignition switch: OFF]BATTERY VOLTAGE
(11 - 14V)
[Ignition switch: ON]0 - 1.0V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)

TROUBLE DIAGNOSIS
EC-761
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Revision: 2004 November 2004 FX35/FX45
ENGINE CONTROL COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOS-
TIC RESULTS
DATA
MONI-
TORDATA
MONI-
TOR
(SPEC)ACTIVE
TESTDTC & SRT
CONFIRMATION
DTC*1FREEZE
FRAME
DATA*2SRT
STATUSDTC
WORK
SUP-
PORT
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor (POS)××××
Camshaft position sensor
(PHASE)××××
Mass air flow sensor×××
Engine coolant temperature sen-
sor×××××
Heated oxygen sensor 1×××××
Heated oxygen sensor 2×××××
Wheel sensor××××
Accelerator pedal position sensor×××
Throttle position sensor×××
Fuel tank temperature sensor××××
EVAP control system pressure
sensor×××
Intake air temperature sensor××××
Knock sensor×
Refrigerant pressure sensor××
Closed throttle position switch
(accelerator pedal position sensor
signal)××
Air conditioner switch××
Park/neutral position (PNP) switch×××
Stop lamp switch×××
Power steering pressure sensor×××
Battery voltage××
Load signal××
Snow mode switch××
Intake valve timing control position
sensor×××
Fuel level sensor×××
ICC steering switch×××
ASCD steering switch×××
ICC brake switch×××
ASCD brake switch×××

EC-766
[VK45DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
BATTERY VOLT [V]××
The power supply voltage of ECM is dis-
played.
ACCEL SEN 1 [V]××

The accelerator pedal position sensor sig-
nal voltage is displayed.
ACCEL SEN 2 signal is converted be
ECM internally. Thus, they differs
from ECM terminal voltage signal. ACCEL SEN 2 [V]×
THRTL SEN 1 [V]××

The throttle position sensor signal voltage
is displayed.
THRTL SEN 2 signal is converted by
ECM internally. Thus, they differs
from ECM terminal voltage signal. THRTL SEN 2 [V]×
FUEL T/TEMP SE
[°C] or [°F]×

The fuel temperature (determined by the
signal voltage of the fuel tank temperature
sensor) is displayed.
INT/A TEMP SE
[°C] or [°F]××

The intake air temperature (determined by
the signal voltage of the intake air tempera-
ture sensor) is indicated.
EVAP SYS PRES [V]×

The signal voltage of EVAP control system
pressure sensor is displayed.
FUEL LEVEL SE [V]×

The signal voltage of the fuel level sensor is
displayed.
START SIGNAL
[ON/OFF]××

Indicates start signal status [ON/OFF] com-
puted by the ECM according to the signals
of engine speed and battery voltage.
After starting the engine, [OFF] is dis-
played regardless of the starter sig-
nal.
CLSD THL POS
[ON/OFF]××

Indicates idle position [ON/OFF] computed
by ECM according to the accelerator pedal
position sensor signal.
AIR COND SIG
[ON/OFF]××

Indicates [ON/OFF] condition of the air con-
ditioner switch as determined by the air
conditioner signal.
P/N POSI SW
[ON/OFF]××

Indicates [ON/OFF] condition from the park/
neutral position (PNP) switch signal.
PW/ST SIGNAL
[ON/OFF]××

[ON/OFF] condition of the power steering
system (determined by the signal voltage of
the power steering pressure sensor signal)
is indicated.
LOAD SIGNAL
[ON/OFF]××

Indicates [ON/OFF] condition from the elec-
trical load signal.
ON: Rear window defogger switch is ON
and/or lighting switch is in 2nd position.
OFF: Both rear window defogger switch
and lighting switch are OFF.
SNOW MODE SW
[ON/OFF]

Indicates [ON/OFF] condition from the
snow mode switch signal.
IGNITION SW
[ON/OFF]×

Indicates [ON/OFF] condition from ignition
switch signal.
HEATER FAN SW
[ON/OFF]×

Indicates [ON/OFF] condition from the
heater fan switch signal.
BRAKE SW
[ON/OFF]

Indicates [ON/OFF] condition from the stop
lamp switch signal.
INJ PULSE-B1
[msec]×

Indicates the actual fuel injection pulse
width compensated by ECM according to
the input signals.
When the engine is stopped, a cer-
tain computed value is indicated.
INJ PULSE-B2
[msec]Monitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks

EC-826
[VK45DE]
DTC P0101 MAF SENSOR
Revision: 2004 November 2004 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.
Diagnostic ProcedureABS00C19
1. INSPECTION START
Which malfunction (A or B) is duplicated?
A or B
A >> GO TO 3.
B >> GO TO 2.
2. CHECK INTAKE SYSTEM
Check the following for connection.

Air duct

Va c u u m h o s e s

Intake air passage between air duct to intake manifold
OK or NG
OK >> GO TO 3.
NG >> Reconnect the parts.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
48 LSensor power supply
(Mass air flow sensor)[Ignition switch: ON]Approximately 5V
51 L/W Mass air flow sensor[Engine is running]

Warm-up condition

Idle speed1.2 - 1.8V
[Engine is running]

Warm-up condition

Engine speed is 2,500 rpm1.7 - 2.4V
67 B/WSensor ground
(Mass air flow sensor / IAT
sensor / Power steering
pressure sensor / EVAP
control system pressure
sensor / Refrigerant pres-
sure sensor / ECT sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
111 W / BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]

More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
11 9
120R
RPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)

DTC P0102, P0103 MAF SENSOR
EC-833
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Revision: 2004 November 2004 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.
Diagnostic ProcedureABS00C1H
1. INSPECTION START
Which malfunction (P0102 or P0103) is duplicated?
P0102 or P0103
P0102 >> GO TO 2.
P0103 >> GO TO 3.
2. CHECK INTAKE SYSTEM
Check the following for connection.

Air duct

Va c u u m h o s e s

Intake air passage between air duct to intake manifold
OK or NG
OK >> GO TO 3.
NG >> Reconnect the parts.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
48 LSensor power supply
(Mass air flow sensor)[Ignition switch: ON]Approximately 5V
51 L/W Mass air flow sensor[Engine is running]

Warm-up condition

Idle speed1.2 - 1.8V
[Engine is running]

Warm-up condition

Engine speed is 2,500 rpm1.7 - 2.4V
67 B/WSensor ground
(Mass air flow sensor / IAT
sensor / Power steering
pressure sensor / EVAP
control system pressure
sensor / Refrigerant pres-
sure sensor / ECT sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
111 W / BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]

More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
11 9
120R
RPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)

EC-1010
[VK45DE]
DTC P0452 EVAP CONTROL SYSTEM PRESSURE SENSOR
Revision: 2004 November 2004 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.
Diagnostic ProcedureABS00C6F
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
32 OREVAP control system pres-
sure sensor[Ignition switch: ON]Approximately 1.8 - 4.8V
48 LSensor power supply
(Mass air flow sensor /
EVAP control system pres-
sure sensor)[Ignition switch: ON]Approximately 5V
67 B/WSensor ground
(Mass air flow sensor / IAT
sensor / Power steering
pressure sensor / EVAP
control system pressure
sensor / Refrigerant pres-
sure sensor / ECT sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
PBIB2195E

DTC P0453 EVAP CONTROL SYSTEM PRESSURE SENSOR
EC-1017
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Revision: 2004 November 2004 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.
Diagnostic ProcedureABS00C6M
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
32 OREVAP control system pres-
sure sensor[Ignition switch: ON]Approximately 1.8 - 4.8V
48 LSensor power supply
(Mass air flow sensor /
EVAP control system pres-
sure sensor)[Ignition switch: ON]Approximately 5V
67 B/WSensor ground
(Mass air flow sensor / IAT
sensor / Power steering
pressure sensor / EVAP
control system pressure
sensor / Refrigerant pres-
sure sensor / ECT sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
PBIB2195E