CHASSIS AND BODY MAINTENANCEMA-29
C
DE
F
G H
I
J
K
M A
B
MA
Revision: November 2009 2006 QX56
CALIPER
Check the caliper for any leaks, repair as necessary.
PA D
Check the pads for wear or damage. Refer to BR-32, "Front Disc
Brake" , BR-33, "Rear Disc Brake" .
Checking Steering Gear and LinkageELS001CD
STEERING GEAR
Check the steering gear housing for looseness, damage and oil
leakage as shown.
Check the steering column connections for looseness.
STEERING LINKAGE
Check the ball joint, dust cover and other component parts for looseness, wear, damage, and grease leak-
age.
Checking Power Steering Fluid and LinesELS001CE
CHECKING FLUID LEVEL
Check the power steering fluid level with the engine off.
Check fluid level on reservoir. Use “HOT ” range at fluid tempera-
tures of 50 ° to 80 °C (122 ° to 176 °F). Use “COLD” range at fluid
temperatures of 0 ° to 30 °C (32 ° to 86 °F).
CAUTION:
Do not overfill.
Refer to MA-11, "Fluids and Lubricants" .
SMA922A
LMA051
SGIA0506E
LGIA0021E
PS-6
POWER STEERING FLUID
Revision: November 20092006 QX56
POWER STEERING FLUIDPFP:KLF20
Checking Fluid LevelEGS000U9
Check power steering fluid level with engine off, referring to the scale
on reservoir tank.
Use HOT range for fluid temperatures of 50° – 80 °C (122 ° – 176° F).
Use COLD range for fluid temperatures of 0 ° – 30° C (32 ° – 86 °F).
CAUTION:
Do not overfill.
Do not reuse any used power steering fluid.
Recommended fluid is Genuine NISSAN PSF or equivalent.
Refer to MA-11, "
RECOMMENDED FLUIDS AND LUBRI-
CANTS" .
Checking Fluid LeakageEGS000UA
Check the hydraulic piping lines for improper attachment and for
leaks, cracks, damage, loose connections, chafing or deterioration.
1. Run engine until fluid temperature reaches 50 ° – 80 °C (122 ° –
176° F) in reservoir tank. Keep engine speed idle.
2. Turn steering wheel right-to-left several times.
3. Hold steering wheel at each “lock” position for five seconds to
check fluid leakage.
CAUTION:
Do not hold steering wheel in a locked position for more
than 10 seconds. (There is the possibility that oil pump may
be damaged.)
4. If fluid leakage at connections is noticed, then loosen flare nut and then retighten. Do not over tighten con- nector as this can damage O-ring, washer and connector.
5. If fluid leakage from oil pump is noticed, check oil pump. Refer to PS-21, "
POWER STEERING OIL
PUMP" .
6. Check steering gear boots for accumulation of fluid indicating a leak from the steering gear.
Air Bleeding Hydraulic SystemEGS000UB
Incomplete air bleeding causes the following. When this happens, bleed air again.
Air bubbles in reservoir tank.
Clicking noise in oil pump.
Excessive buzzing in oil pump.
NOTE:
When vehicle is stationary or while steering wheel is being turned slowly, some noise may be heard from
oil pump or gear. This noise is normal and does not affect any system.
1. Stop engine, and then turn steering wheel fully to right and left several times. CAUTION:
Do not allow steering fluid reservoir tank to go below the MIN level line. Check tank frequently and
add fluid as needed.
2. Run engine at idle speed. Turn steering wheel fully right and then fully left, hold for about three seconds. Then check for fluid leakage.
3. Repeat step 2 several times at about three second intervals. CAUTION:
Do not hold steering wheel in the locked position for more than 10 seconds. (There is the possibil-
ity that oil pump may be damaged.)
4. Check for air bubbles or cloudy fluid.
5. If air bubbles or cloudiness still exists, stop engine, perform steps 2 and 3 again until air bubbles or cloud- iness does not exist.
6. Stop engine, check fluid level.
LGIA0021E
SGIA0506E
STEERING WHEELPS-7
C
DE
F
H I
J
K L
M A
B
PS
Revision: November 2009 2006 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-38, "
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-21, "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
POWER STEERING OIL PUMPPS-21
C
DE
F
H I
J
K L
M A
B
PS
Revision: November 2009 2006 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, repair or replace oil pump. Refer to PS-22, "Disassem-
bly 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-12, "
Removal and Installation" .
3. Remove air duct assembly. Refer to EM-15, "
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-13,
"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-23, "
HYDRAU-
LIC LINE" .
8. Remove mounting bolts, then remove power steering pump.
INSTALLATION
Installation is in the reverse order of removal. Refer to PS-23, "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 valve KV48103500
(J26357 and J26357-10)
Oil pump side Connector A and
O-ring
KV48105300-4 and 5295262U10
(
— )
Eye-bolt and O-ring KV48105300-3 and 5295262U00
(
— )
High pressure
piping side Connector B and
O-ring
KV48105300-1 and 5295262U00
(
— )
Nut KV48105300-2
(
— )
Relief oil pressure
: 9.0 – 9.8 mPa (91.77 – 99.93 kg/cm2 , 1305.34 – 1421.37 psi)
SGIA0570E
SIDE CURTAIN AIR BAG MODULESRS-53
C
DE
F
G
I
J
K L
M A
B
SRS
Revision: November 2009 2006 QX56
SIDE CURTAIN AIR BAG MODULEPFP:985P0
Removal and InstallationEHS00171
REMOVAL
CAUTION:
Do not attempt to repair or replace damaged direct-connect SRS component connectors. If a
direct-connect harness connector is damaged, the harness must be replaced.
Before servicing the SRS, turn the ignition switch off, disconnect both battery cables and wait at
least 3 minutes.
When servicing the SRS, do not work from directly in front of air bag module.
1. Remove headlining. Refer to EI-38, "
Removal and Installation" .
2. Disconnect front and rear side curtain air bag module connectors.
For removal/installation of the direct-connect SRS connectors, refer to SRS-7, "Direct-connect SRS
Component Connectors" .
3. Remove the bolts in order starting at the front or rear, and remove the side curtain air bag module.
CAUTION:
When servicing the SRS, do not work from directly in front of air bag module.
Do not insert any foreign objects (screwdriver, etc.) into air bag module or harness connectors.
Do not disassemble air bag module.
Do not expose the air bag module to temperatures exceeding 90° C (194°F).
Replace side curtain air bag module if it has been dropped
or sustained an impact.
Do not allow oil, grease or water to come in contact with the
air bag module.
1. Rear side curtain air bag module
connector 2. Front side curtain air bag module
connector ⇐
Vehicle front
WHIA0294E
SBF814E
TF-18
ALL-MODE 4WD SYSTEM
Revision: November 20092006 QX56
4WD mode. Setting the vehicle in the 2WD mode requires no pressure buildup. In other words, pressure force
applied to the wet-multiplate clutch becomes zero.
CLUTCH PRESSURE SOLENOID VALVE
The clutch pressure solenoid valve distributes torque (front and rear) in AUTO mode.
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: November 20092006 QX56
COMPONENTS FUNCTION
CAN CommunicationEDS002HC
SYSTEM DESCRIPTION
Refer to LAN-26, "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-
sor Detects 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 lamp Indicates 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.
TCM Transmits the following signals via CAN communication to transfer control unit.
Output shaft revolution signal
A/T position indicator signal (PNP switch signal)
ECM Transmits the following signals via CAN communication to transfer control unit.
Engine speed signal
Accelerator pedal position signal
TF-46
TROUBLE DIAGNOSIS
Revision: November 20092006 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.TF-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.
TF-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