2005 INFINITI QX4 engine oil

STEERING WHEEL
PS-7
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PS
Revision: October 20052005 QX56
STEERING WHEELPFP:48430
On-Vehicle Inspection and ServiceEGS000UC
CHECKING CONDITION OF INSTALLATION

Check installation condition of steering gear assembly, front suspension, axle and steering column.

Check if movement exists when steering wheel is moved up and down, to the left and right and to the axial
direction.

Check if the mounting nuts for steering gear assembly are loose.
Refer to PS-15, "
POWER STEERING GEAR AND LINKAGE" .
CHECKING STEERING WHEEL PLAY
1. Turn tires straight ahead, start engine, then turn steering wheel to the left and right lightly, and measure
steering wheel movement on the outer circumference when steering wheel is turned up to the point where
tires start moving.
CHECKING NEUTRAL POSITION ON STEERING WHEEL

Check neutral position on steering wheel after confirming that front wheel alignment is correct. Refer to
FSU-6, "
Front Wheel Alignment" .
1. Turn tires straight ahead, check if steering wheel is in the neutral position.
2. If it is not in the neutral position, remove steering wheel and reinstall it correctly.
3. If the neutral position cannot be attained by repositioning the steering wheel two teeth or less on steering
stem, loosen tie-rod lock nuts of steering outer sockets, then adjust tie-rods by the same amount in the
opposite direction.
CHECKING STEERING WHEEL TURNING FORCE
1. Park vehicle on a level, dry surface and set parking brake.
2. Start engine.
3. Bring power steering fluid up to operating temperature of 60° – 80°C (140° – 176°F).
4. Tires need to be inflated to specified pressure. Refer to WT-34, "
Tire" .
5. Check steering wheel turning force using Tool when steering
wheel has been turned 360° from the neutral position.
6. If steering wheel turning force is out of specification, inspect the
following:

Steering column. Refer to PS-11, "INSPECTION AFTER
REMOVAL" .

Power steering oil pump. Refer to PS-26, "CHECKING
RELIEF OIL PRESSURE" .
7. If steering column and power steering oil pump meet specifications, replace steering gear. Refer to PS-15,
"Removal and Installation" . End play of the axial direction for steering wheel : 0 mm (0 in)
LGIA0024E
Steering wheel play on the outer circumference : 0 − 35 mm (0 − 1.38 in)
Tool number : J-44372
Steering wheel
turning force: 39 N (4 kg-f, 9 lb-f) or less
WGIA0035E

PS-26
POWER STEERING OIL PUMP
Revision: October 20052005 QX56
POWER STEERING OIL PUMPPFP:49110
On-Vehicle Inspection and ServiceEGS000UJ
CHECKING RELIEF OIL PRESSURE
CAUTION:
Before starting work, confirm belt tension is proper.
1. Connect Tool between oil pump discharge connector and high
pressure hose and then bleed air from the hydraulic circuit.
2. Start engine. Allow engine to run until tank temperature reaches 50 – 80°C (122 – 176°F).
CAUTION:

Warm up engine with shut-off valve fully opened. If engine is started with shut-off valve closed,
fluid pressure in power steering pump increases to maximum. This will raise fluid temperature
excessively.

Be careful not to contact hose with belt when engine is started.
3. With engine at idle, close shut-off valve and read the relief oil pressure.
CAUTION:
Do not close shut-off valve of pressure gauge for more than 10 seconds.
4. After measurement, open shut-off valve slowly.

If relief oil pressure is outside the specification, disassemble and repair oil pump. Refer to PS-17, "Dis-
assembly and Assembly" .
5. After inspection, disconnect oil pressure gauge and oil pressure gauge adapter from hydraulic circuit, con-
nect oil pump discharge connector and high pressure hose. Add fluid and bleed air from hydraulic circuit
thoroughly. Refer to PS-6, "
Air Bleeding Hydraulic System" .
Removal and InstallationEGS000UK
REMOVAL
1. Drain power steering fluid from reservoir tank.
2. Remove engine room cover. Refer to EM-11, "
Removal and Installation" .
3. Remove air duct assembly. Refer to EM-14, "
Removal and Installation" .
4. Remove power steering reservoir tank.
5. Remove serpentine drive belt belt from auto tensioner and power steering pump. Refer to EM-12,
"Removal and Installation" .
6. Disconnect pressure sensor electrical connector.
7. Remove high pressure and low pressure piping from power steering oil pump. Refer to PS-31, "
HYDRAU-
LIC LINE" .
8. Remove mounting bolts, then remove power steering pump.
INSTALLATION
Installation is in the reverse order of removal. Refer to PS-31, "HYDRAULIC LINE" for tightening torque.

After installation, bleed air. Refer to PS-6, "Air Bleeding Hydraulic System" .
NOTE:
Belt tension is automatic and requires no adjustment.
Tool number:
Pressure gauge and shut-off valveKV48103500
(J26357 and J26357-10)
Oil pump sideConnector A and
O-ringKV48105300-4 and 5295262U10
(—)
Eye-bolt and O-ringKV48105300-3 and 5295262U00
(—)
High pressure
piping sideConnector B and
O-ringKV48105300-1 and 5295262U00
(—)
NutKV48105300-2
( — )
Relief oil pressure
: 9.0 – 9.8 mPa (91.77 – 99.93 kg/cm2 , 1305.34 – 1421.37 psi)
SGIA0570E

PRECAUTIONS
RSU-3
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RSU
Revision: October 20052005 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EES001GX
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WA RN ING:

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for Rear SuspensionEES001GY

When installing the rubber bushings, the final tightening must be done under unladen condition and with
the tires on level ground. Oil will shorten the life of the rubber bushings, so wipe off any spilled oil immedi-
ately.

Unladen condition means the fuel tank, engine coolant and lubricants are at the full specification. The
spare tire, jack, hand tools, and mats are in their designated positions.

After installing suspension components, check the wheel alignment.

Caulking nuts are not reusable. Always use new caulking nuts for installation. New caulking nuts are pre-
oiled, do not apply any additional lubrication.

REAR SUSPENSION MEMBER
RSU-33
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RSU
Revision: October 20052005 QX56
INSTALLATION
Installation is in the reverse order of removal.

When raising the rear suspension member assembly, use the
locating pins to align the rear suspension member to the vehicle
body.

When installing the upper and lower rubber seats for the rear
coil springs, the arrow embossed on the rubber seats must point
out toward the wheel and tire assembly.

To connect the rear load leveling air suspension hoses, the lock
ring must be fully seated in the fitting. Insert the hose “B” into the
lock ring “A” until the lock ring “A” is touching the hose “B” as
shown. Pull on the hose to check that it is securely inserted.

Perform the final tightening of the nuts and bolts for the links (rubber bushing) under unladen condition
(unladen condition means that the fuel tank, engine coolant and lubricants are at the full specification, and
the spare tire, jack, hand tools, and mats are in their designated positions) with the tires on level ground.

Check the wheel alignment. Refer to RSU-47, "Wheel Alignment" .
LEIA0083E
LEIA0076E
LEIA0078E

RSU-48
SERVICE DATA AND SPECIFICATIONS (SDS)
Revision: October 20052005 QX56
Wheelarch Height (Unladen*1 )EES001HV
Unit: mm (in)
*1: Fuel, engine coolant and engine oil full. Spare tire, jack, hand tools and mats in designated positions.
*2: Verify the vehicle height. If vehicle height is not within ± 10 mm (0.39 in) of the specification, perform the control unit initialization pro-
cedure. Refer to RSU-46, "
Initialization Procedure" . Suspension type
Air leveling*
2
Applied model4x2 4x4
Front wheelarch height (Hf)913
(35.94)931
(36.65)
Rear wheelarch height (Hr)912
(35.91)932
(36.69)
LEIA0085E

TF-18
ALL-MODE 4WD SYSTEM
Revision: October 20052005 QX56
LINE PRESSURE SWITCH

With the transfer system design, control of the oil pressure provides the transmission of drive torque to the
front wheels. The main pressure to control the oil pressure is referred to as the line pressure.

The line pressure switch determines whether or not adequate line pressure has built up under different
operating conditions.

The line pressure switch turns ON when line pressure is produced.

The line pressure switch senses line pressure abnormalities and turns the 4WD warning lamp ON.
CLUTCH PRESSURE SWITCH

The clutch pressure switch determines whether or not adequate clutch pressure has built up under differ-
ent operating conditions.

The clutch pressure switch turns ON when clutch pressure is produced.

The clutch pressure switch senses clutch pressure abnormalities and turns the 4WD warning lamp ON.
TRANSFER FLUID TEMPERATURE SENSOR
The transfer temperature sensor detects the transfer fluid temperature and sends a signal to the transfer con-
trol unit.
TRANSFER CONTROL UNIT

Transfer control unit controls transfer control device by input signals of each sensor and each switch.

Self-diagnosis can be done.
TRANSFER CONTROL DEVICE
The transfer control device changes the state of transfer assembly between 2WD, AUTO, 4H⇔4LO with the
2WD, AUTO, 4H and 4LO signals of 4WD shift switch.
NOTE:

To shift between 4H⇔4LO, stop the vehicle, depress the brake pedal and shift the transmission selector
to the "N" position. Depress and turn the 4WD shift switch. The shift switch will not shift to the desired
mode if the transmission is not in "N" or the vehicle is moving. The 4LO indicator lamp will be lit when the
4LO is engaged.

Actuator motor and actuator position switch are integrated.
4WD SHIFT SWITCH AND INDICATOR LAMP
4WD Shift Switch
The 4WD shift switch allows selection from 2WD, AUTO, 4H or 4LO.
4WD Shift Indicator Lamp

Displays driving conditions selected by 4WD shift switch with 2WD, AUTO and 4H indicators while engine
is running. (When 4WD warning lamp is turned on, all 4WD shift indicator lamps are turned off.)

Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.
4LO Indicator Lamp

Displays 4LO condition while engine is running. 4LO indicator lamp flashes if transfer gear does not shift
completely under 2WD, AUTO, 4H⇔4LO. (When 4WD warning lamp is turned on, 4LO indicator lamp is
turned off.)

Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.

TF-20
ALL-MODE 4WD SYSTEM
Revision: October 20052005 QX56
COMPONENTS FUNCTION
CAN CommunicationEDS002HC
SYSTEM DESCRIPTION
Refer to LAN-5, "CAN COMMUNICATION" .
Component parts Function
Transfer control unit Controls transfer control device and control valves.
Transfer control device Actuator motor and actuator position switch are integrated so as to switch driving types.
2-4WD shift solenoid valve Controls oil pressure and allows selection between 2WD and 4WD.
Clutch pressure solenoid valve Controls oil pressure and distributes torque (front and rear).
Line pressure switch Detects line pressure.
Clutch pressure switch Detects clutch pressure.
Transfer fluid temperature sen-
sorDetects transfer fluid temperature.
Wait detection switch Detects whether or not 4WD lock gear is locked.
Neutral-4LO switch Detects that transfer is under neutral-4LO condition (or shifting through neutral).
ATP switch Detects that transfer is under neutral condition.
4WD shift switch Allows selection from 2WD, AUTO, 4H or 4LO.
4WD warning lamp

Illuminates if malfunction is detected in electrical system of 4WD system.

There is 1 blink every 2 seconds if rotation difference of front wheels and rear wheels is large.

There is 2 blinks every 1 second if high transfer fluid temperature is detected.
ATP warning lampIndicates that A/T parking mechanism does not operate when A/T selector lever is in “P” position
and transfer is under neutral condition.
4WD shift indicator lamp Displays driving condition selected by 4WD shift switch.
4LO indicator lamp Displays 4LO condition.
ABS actuator and electric unit
(control unit)Transmits vehicle speed signal via CAN communication to transfer control unit.
TCMTransmits the following signals via CAN communication to transfer control unit.

Output shaft revolution signal

A/T position indicator signal (PNP switch signal)
ECMTransmits the following signals via CAN communication to transfer control unit.

Engine speed signal

Accelerator pedal position signal

TF-46
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
CAUTION:

If “CAN COMM CIRCUIT [U1000]” is displayed with other DTCs, first perform the trouble diagnosis for CAN communica-
tion line.

If “VHCL SPEED SEN·AT [P1808]”, “ABS OP SIG [P1830]”, “VDC OP SIG [P1831]” or “TCS OP SIG [P1832]” is displayed,
first perform the trouble diagnosis for ABS system.

If “VHCL SPEED SEN·AT [P1808]”, is displayed, first perform the trouble diagnosis for A/T system.
NOTE:

If "SHIFT ACT POSI SW [P1818]" or “SHIFT ACT CIR [P1819]” is displayed, first erase self-diagnostic results. ("SHIFT ACT POSI
SW [P1818]" or “SHIFT ACT CIR [P1819]” may be displayed after installing transfer control unit or transfer assembly.)

If “CL PRES SW [P1827]” or “LINE PRES SW [P1828]” is displayed only while driving in reverse, check the continuity of “R” posi-
tion on A/T PNP switch. When there is nothing wrong with the electrical system, check the hydraulic system. SHIFT ACT CIR
[P1819]

Transfer control device actuator circuit is shorted or open. (Mal-
functions are detected when transfer shift relay circuit is open/
shorted or relay monitor circuit is open/shorted.)

Malfunction occurs in transfer control device drive circuit.

Malfunction is detected in transfer shut off relay.TF-81, "
Transfer Control Device"
Malfunction is detected in transfer shut off relay.TF-54, "Power Supply Circuit For
Transfer Control Unit"
ENGINE SPEED SIG
[P1820]
Malfunction is detected in engine speed signal that is output from
ECM through CAN communication.

Improper signal is input while driving.TF-85, "
Engine Speed Signal
(ECM)"
DUTY SOLENOID
[P1822]
Proper voltage is not applied to clutch pressure solenoid valve
due to open or short circuit.TF-86, "Clutch Pressure Sole-
noid"
2-4WD SOLENOID
[P1823]
Proper voltage is not applied to 2-4WD solenoid valve due to
open or short circuit.TF-91, "2-4WD Solenoid"
MOTOR RELAY
[P1824]
Motor does not operate properly due to open or short circuit in
transfer motor or motor relay.TF-95, "Transfer Motor"
OIL TEMP SEN
[P1826]
Signal voltage from fluid temperature sensor is abnormally high
(Transfer fluid temperature is abnormally low) while driving.TF-102, "Transfer Fluid Temper-
ature"
CLUTCH PRES SW
[P1827]
Improper signal from clutch pressure switch is input due to open
or short circuit.

Malfunction occurs in clutch pressure switch or hydraulic circuit.TF-105, "
Clutch Pressure
Switch"
LINE PRES SW
[P1828]
Improper signal from line pressure switch is input due to open or
short circuit.

Malfunction occurs in line pressure switch or hydraulic circuit.TF-108, "
Line Pressure Switch"
THROTTLE POSI SEN
[P1829]

Malfunction is detected in accelerator pedal position signal that is
output from ECM through CAN communication.

Signal voltage from accelerator pedal position sensor is abnor-
mally high or low.T F - 111 , "
Throttle Position Signal
(ECM)"
ABS OP SIG
[P1830]
Malfunction is detected in ABS operation signal that is output
from ABS actuator and electric unit (control unit) through CAN
communication.T F - 111 , "ABS Operation Signal
(ABS)"
VDC OP SIG
[P1831]
Malfunction is detected in VDC operation signal that is output
from ABS actuator and electric unit (control unit) through CAN
communication.TF-112, "VDC Operation Signal
(ABS)"
TCS OP SIG
[P1832]
Malfunction is detected in TCS operation signal that is output
from ABS through CAN communication.TF-112, "TCS Operation Signal
(ABS)"
CAN COMM CIRCUIT
[U1000]
Malfunction has been detected from CAN communication line.TF-113, "CAN Communication
Line"
NO DTC IS DETECTED.
FURTHER TESTING MAY
BE REQUIRED.

No NG item has been detected. — Items (CONSULT-II screen
terms)Diagnostic item is detected when... Check item