2004 INFINITI QX56 Crankshaft sensor

TRANSMISSION ASSEMBLY
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Revision: August 20072004 QX56
TRANSMISSION ASSEMBLYPFP:31020
Removal and Installation (4x2)UCS002J E
COMPONENTS
REMOVAL
CAUTION:
When removing the A/T assembly from engine, first remove the crankshaft position sensor (POS) from
the A/T assembly.
Be careful not to damage sensor edge.
1. Disconnect the negative battery terminal.
2. Remove engine cover.
3. Remove A/T fluid indicator gauge.
4. Remove engine under cover with power tool.
5. Remove exhaust front tube and center muffler with power tool. Refer to EX-3, "
Removal and Installation" .
6. Remove rear propeller shaft. Refer to PR-9, "
REMOVAL" .
7. Remove A/T control cable. Refer to AT- 2 3 3 , "
SHIFT CONTROL SYSTEM" .
1. A/T fluid indicator pipe 2. A/T fluid indicator 3. O-ring
4. Transmission assembly 5. Fluid cooler tube 6. A/T cross member
7. Insulator 8. Copper washers
LCIA0333E

AT-256
TRANSMISSION ASSEMBLY
Revision: August 20072004 QX56
8. Remove crankshaft position sensor (POS) from A/T assembly.
9. Remove fluid cooler tube.
10. Remove dust cover from converter housing part.
11. Turn crankshaft, and remove the four tightening bolts for drive
plate and torque converter.
CAUTION:
When turning crankshaft, turn it clockwise as viewed from
the front of the engine.
12. Support A/T assembly with a transmission jack.
CAUTION:
When setting the transmission jack, be careful not to allow
it to collide against the drain plug.
13. Remove cross member with power tool.
14. Remove air breather hose. Refer to AT-253, "
Removal and
Installation" .
15. Disconnect A/T assembly connector.
16. Remove A/T fluid indicator pipe from A/T assembly.
17. Plug up openings such as the fluid charging pipe hole, etc.
18. Remove the A/T assembly to engine bolts with power tool.
19. Remove A/T assembly from vehicle using Tool and a transmis-
sion jack.

Secure torque converter to prevent it from dropping.

Secure A/T assembly to a transmission jack.
INSPECTION
Installation and Inspection of Torque Converter

After inserting a torque converter to a transmission, be sure to
check dimension A to ensure it is within the reference value
limit.
LCIA0334E
Tool number : — (J-47002)
LCIA0335E
SCIA0499E
Dimension A : 24.0 mm (0.94 in) or more
SAT0 1 7B

AT-258
TRANSMISSION ASSEMBLY
Revision: August 20072004 QX56
Removal and Installation (4x4) UCS002J F
COMPONENTS
REMOVAL
CAUTION:
When removing the A/T assembly from engine, first remove the crankshaft position sensor (POS) from
the A/T assembly.
Be careful not to damage sensor edge.
1. Disconnect the negative battery terminal.
2. Remove engine cover with power tool.
3. Remove A/T fluid indicator.
4. Remove engine under cover with power tool.
5. Remove exhaust front tube and center muffler with power tool. Refer to EX-3, "
Removal and Installation" .
6. Remove propeller shaft. Refer to PR-5, "
REMOVAL" (front), or PR-9, "REMOVAL" (rear).
7. Remove A/T control cable. Refer to AT-233, "
SHIFT CONTROL SYSTEM" .
1. A/T fluid indicator pipe 2. A/T fluid indicator 3. O-ring
4. Transmission assembly 5. Fluid cooler tube 6. Copper washer
7. A/T cross member 8. Insulator
WCIA0257E

TRANSMISSION ASSEMBLY
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Revision: August 20072004 QX56
8. Remove crankshaft position sensor (POS) from A/T assembly.
9. Disconnect A/T fluid cooler tube from A/T assembly.
10. Remove dust cover from converter housing part.
11. Turn crankshaft, and remove the four tightening bolts for drive
plate and torque converter.
CAUTION:
When turning crankshaft, turn it clockwise as viewed from
the front of the engine.
12. Support A/T assembly with a transmission jack.
CAUTION:
When setting the transmission jack, be careful not to allow
it to collide against the drain plug.
13. Remove cross member with power tool.
14. Tilt the transmission slightly to keep the clearance between body
and transmission, and then disconnect air breather hose from charging pipe. Refer to AT- 2 5 3 , "
Removal
and Installation" .
15. Disconnect A/T assembly connector and transfer unit connector.
16. Remove A/T fluid indicator pipe.
17. Plug up openings such as the fluid charging pipe hole, etc.
18. Remove A/T assembly to engine bolts with power tool.
19. Remove A/T assembly from vehicle using Tool and a transmis-
sion jack.

Secure torque converter to prevent it from dropping.

Secure A/T assembly to a transmission jack.
NOTE:
The actual special service Tool may differ from Tool shown.
20. Remove transfer from A/T assembly. Refer to TF-109,
"REMOVAL AND INSTALLATION" .
INSPECTION
Installation and Inspection of Torque Converter

After inserting a torque converter to a transmission, be sure to
check dimension A to ensure it is within the reference value
limit.
LCIA0334E
Tool number : — (J-47002)
LCIA0335E
SCIA0499E
Dimension A : 24.0 mm (0.94 in) or more
SAT0 1 7B

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Revision: August 20072004 QX56 Component Inspection ......................................... 582
Removal and Installation ...................................... 582
IGNITION SIGNAL .................................................. 583
Component Description ........................................ 583
Wiring Diagram .................................................... 584
Diagnostic Procedure ........................................... 589
Component Inspection ......................................... 593
Removal and Installation ...................................... 594
INJECTOR CIRCUIT ............................................... 595
Component Description ........................................ 595
CONSULT-II Reference Value in Data Monitor Mode
. 595
Wiring Diagram .................................................... 596
Diagnostic Procedure ........................................... 597
Component Inspection ......................................... 600
Removal and Installation ...................................... 600
FUEL PUMP CIRCUIT ............................................ 601
Description ........................................................... 601
CONSULT-II Reference Value in Data Monitor Mode
. 601
Wiring Diagram .................................................... 602
Diagnostic Procedure ........................................... 603
Component Inspection ......................................... 606
Removal and Installation ...................................... 606
REFRIGERANT PRESSURE SENSOR ................. 607
Component Description ........................................ 607
Wiring Diagram .................................................... 608
Diagnostic Procedure ........................................... 609
Removal and Installation ....................................... 611
ELECTRICAL LOAD SIGNAL ................................ 612
Description ........................................................... 612
CONSULT-II Reference Value in Data Monitor Mode
. 612
Diagnostic Procedure ........................................... 612
ICC BRAKE SWITCH ............................................. 613
Component Description ........................................ 613
CONSULT-II Reference Value in Data Monitor Mode
. 613
Wiring Diagram .................................................... 614
Diagnostic Procedure ........................................... 615
Component Inspection ......................................... 619
ASCD BRAKE SWITCH ......................................... 621
Component Description ........................................ 621CONSULT-II Reference Value in Data Monitor Mode
.621
Wiring Diagram .....................................................622
Diagnostic Procedure ...........................................623
Component Inspection ..........................................627
ASCD INDICATOR ..................................................628
Component Description ........................................628
CONSULT-II Reference Value in Data Monitor Mode
.628
Wiring Diagram .....................................................629
Diagnostic Procedure ...........................................630
MIL AND DATA LINK CONNECTOR ......................631
Wiring Diagram .....................................................631
EVAPORATIVE EMISSION SYSTEM .....................633
Description ............................................................633
Component Inspection ..........................................636
Removal and Installation ......................................637
How to Detect Fuel Vapor Leakage ......................637
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ....................................................................640
System Description ...............................................640
Diagnostic Procedure ...........................................641
Component Inspection ..........................................643
POSITIVE CRANKCASE VENTILATION ...............645
Description ............................................................645
Component Inspection ..........................................645
AUTOMATIC SPEED CONTROL DEVICE (ASCD) .647
System Description ...............................................647
Component Description ........................................648
SERVICE DATA AND SPECIFICATIONS (SDS) ....649
Fuel Pressure .......................................................649
Idle Speed and Ignition Timing .............................649
Calculated Load Value ..........................................649
Mass Air Flow Sensor ...........................................649
Intake Air Temperature Sensor .............................649
Engine Coolant Temperature Sensor ...................649
A/F Sensor 1 Heater .............................................649
Heated Oxygen sensor 2 Heater ..........................649
Crankshaft Position Sensor (POS) .......................649
Camshaft Position Sensor (PHASE) ....................649
Throttle Control Motor ...........................................649
Injector ..................................................................650
Fuel Pump ............................................................650

PRECAUTIONS
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Revision: August 20072004 QX56

Do not disassemble ECM.

If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-control at its initial value.
Engine operation can vary slightly when the terminal is dis-
connected. However, this is not an indication of a malfunc-
tion. Do not replace parts because of a slight variation.

When connecting ECM harness connector, fasten it
securely with a lever as far as it will go as shown in the fig-
ure.

When connecting or disconnecting pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM
pin terminal, when connecting pin connectors.

Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge)
voltage to develop in coil and condenser, thus resulting in
damage to ICs.

Keep engine control system harness at least 10 cm (4 in)
away from adjacent harness, to prevent engine control sys-
tem malfunctions due to receiving external noise, degraded
operation of ICs, etc.

Keep engine control system parts and harness dry.

Before replacing ECM, perform ECM Terminals and Refer-
ence Value inspection and make sure ECM functions prop-
erly. Refer to EC-96, "
ECM Terminals and Reference Value"
.

Handle mass air flow sensor carefully to avoid damage.

Do not disassemble mass air flow sensor.

Do not clean mass air flow sensor with any type of deter-
gent.

Do not disassemble electric throttle control actuator.

Even a slight leak in the air intake system can cause seri-
ous incidents.

Do not shock or jar the camshaft position sensor (PHASE), crankshaft position sensor (POS).
PBIB11 64 E
BBIA0387E
PBIB0090E
MEF040D

ENGINE CONTROL SYSTEM
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Revision: August 20072004 QX56
System ChartUBS00GZD
*1: This sensor is not used to control the engine system. This is used only for the on board diagnosis.
*2: This sensor is not used to control the engine system under normal conditions.
*3: This input signal is sent to the ECM through CAN communication line.
*4: This output signal is sent from the ECM through CAN communication line.Input (Sensor) ECM Function Output (Actuator)

Camshaft position sensor (PHASE)

Crankshaft position sensor (POS)

Mass air flow sensor

Engine coolant temperature sensor

A/F sensor 1

Throttle position sensor

Accelerator pedal position sensor

Park/neutral position (PNP) switch

Intake air temperature sensor

Power steering pressure sensor

Ignition switch

Battery voltage

Knock sensor

Refrigerant pressure sensor

Stop lamp switch

ASCD steering switch

ASCD brake switch

Fuel level sensor*1 *3

EVAP control system pressure sensor

Fuel tank temperature sensor*1

Heated oxygen sensor 2*2

TCM (Transmission control module)*3

ABS actuator and electric unit (control unit)*3

Air conditioner switch*3

Wheel sensor*3

Electrical load signal*3
Fuel injection & mixture ratio control Fuel injector
Electronic ignition system Power transistor
Nissan torque demand control system

Electric throttle control actuator

Fuel injector
Fuel pump control Fuel pump relay
ASCD vehicle speed control Electric throttle control actuator
On board diagnostic system
MIL (On the instrument panel)*
4
A/F sensor 1 heater control A/F sensor 1 heater
Heated oxygen sensor 2 heater control Heated oxygen sensor 2 heater
EVAP canister purge flow controlEVAP canister purge volume control
solenoid valve
Air conditioning cut control
Air conditioner relay*
4
Cooling fan control
Cooling fan relay*4
ON BOARD DIAGNOSIS for EVAP system EVAP canister vent control valve

EC-26Revision: August 2007
ENGINE CONTROL SYSTEM
2004 QX56
Multiport Fuel Injection (MFI) SystemUBS00GZE
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 both 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
controlFuel injector Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
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
Knock sensor Engine knocking condition
Battery
Battery voltage*
3
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit)*
2VDC/TCS operation command
Air conditioner switch*
2Air conditioner operation
Wheel sensor*
2Vehicle speed