2007 INFINITI QX56 tire pressure

REAR SUSPENSION MEMBER
RSU-27
< SERVICE INFORMATION >
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Rear Load Leveling Air Suspension System
REMOVAL
1. Use the CONSULT-II “EXHAUST SOLENOID” active test to release the air pressure from the rear load
leveling air suspension system.
2. Disconnect the electrical connectors for the height sensor and the rear load leveling air suspension com-
pressor assembly.
3. Unclip the rubber cover to access the rear load leveling air suspension compressor assembly.
4. Disconnect the rear load leveling air suspension hoses at the
rear load leveling air suspension compressor assembly.
• To disconnect the hoses, push in on the lock ring using a suit-
able tool and pull the hose out.
5. Remove both of the rear wheel and tire assemblies using power
tool.
6. Remove the brake caliper without disconnecting the brake
hoses, using power tool. Reposition the brake caliper out of the
way using a suitable wire. Refer to BR-25, "
Removal and Instal-
lation of Brake Caliper and Disc Rotor" .
CAUTION:
10. Shock absorber 11. Suspension arm 12. Lower rubber seat
13. Coil spring 14. Upper rubber seat 15. Rear suspension member
16. Spare tire bracket 17. Bound bumper
AWEIA0076ZZ
1. Rear load leveling air suspension
hose, RH2. Shock absorber, RH 3. Height sensor
4. Rear load leveling air suspension
hose, LH5. Shock absorber, LH 6. Rear load leveling air suspension
compressor assembly (includes the
bracket and rubber cover)
⇐Front
LEIA0074E

RSU-30
< SERVICE INFORMATION >
SHOCK ABSORBER
SHOCK ABSORBER
Removal and InstallationINFOID:0000000003532673
REMOVAL
1. Remove the wheel and tire assembly using power tool. Refer to WT-7, "Rotation".
2. Use CONSULT-II “EXHAUST SOLENOID” active test to release the air pressure from the rear load level-
ing air suspension system.
3. Remove the four clips and remove the rear fender protector, front.
4. Disconnect the rear load leveling air suspension hose from the
shock absorber.
• To disconnect the hose, push in on the lock ring using a suit-
able tool and pull the air hose out.
5. Remove the shock absorber upper and lower end bolts using
power tool.
6. Remove the shock absorber.
CAUTION:
Do not damage the rubber boot on the shock absorber.
INSTALLATION
Installation is in the reverse order of removal.
• Tighten the shock absorber bolts to specification. Refer to RSU-21, "
Component".
INSPECTION AFTER INSTALLATION
• Check the shock absorber for any air leaks or damage to the rubber boot.
• Check the shock absorber for smooth operation through a full stroke, both compression and extension.
• Check piston rod for cracks, deformation or other damage and replace if necessary.
LEIA0081E
LEIA0082E

FRONT LOWER LINK
RSU-33
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FRONT LOWER LINK
Removal and InstallationINFOID:0000000003532675
REMOVAL
1. Remove the wheel and tire assembly using power tool.
2. Use CONSULT-II "EXHAUST SOLENOID" active test to release the air pressure from the rear load level-
ing air suspension system.
3. Remove the shock absorber lower end bolt.
4. Remove the adjusting bolt and nut, and the bolt and nut, from
the front lower link and rear suspension member using power
tool.
5. Remove the front lower link pinch bolt and nut on the knuckle
side using power tool.
6. Disconnect the front lower link from the knuckle using a soft
hammer.
CAUTION:
Do not damage the ball joint with the soft hammer.
7. Remove the front lower link.
INSPECTION AFTER REMOVAL
• Check the front lower link and bushing for any deformation, crack, or damage. Replace if necessary.
• Check the rubber bushing for damage, cracks and deformation. Replace the front lower link and bushing if
necessary.
• Before checking, turn the ball joint at least 10 revolutions so that the ball joint is properly broken in.
LEIA0082E
LEIA0086E

REAR LOWER LINK & COIL SPRING
RSU-35
< SERVICE INFORMATION >
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REAR LOWER LINK & COIL SPRING
Removal and InstallationINFOID:0000000003532676
REMOVAL
1. Remove the wheel and tire assembly using power tool. Refer to WT-7, "Rotation" .
2. Use CONSULT-II "EXHAUST SOLENOID" active test to release the air pressure from the rear load level-
ing air suspension system.
3. For removing the LH rear lower link and coil spring, remove the
height sensor arm bracket bolt from the LH rear lower link.
4. Set a suitable jack to relieve the coil spring tension from the rear
lower link.
WARNING:
Do not compress the coil spring when setting the jack.
5. Loosen the rear lower link adjusting bolt and nut connected to
the rear suspension member, using power tool.
6. Remove the rear lower link bolt and nut from the knuckle using
power tool.
7. Slowly lower the suitable jack to release the coil spring tension. Then remove the upper rubber seat, coil
spring, and lower rubber seat from the rear lower link.
LEIA0080E
LEIA0077E
LEIA0009E
LEIA0077E

SRS-50
< SERVICE INFORMATION >
COLLISION DIAGNOSIS
For Side and Rollover Collision
INFOID:0000000003532883
Check the SRS components using the following table.
• After the work is completed, perform self-diagnosis to check that no malfunction is detected. Refer to SRS-
20, "SRS Operation Check" .
WHEN SRS IS ACTIVATED IN THE SIDE OR ROLLOVER COLLISION
1. Replace the following components:
- Front seat back assembly (on the side on which side air bag is activated)
- Diagnosis sensor unit
- (LH or RH) side air bag (satellite) sensor (on the side on which side air bag is activated)
2. Check the SRS components and the related parts using the following table.
- Replace any SRS components and the related parts showing visible signs of damage (dents, cracks,
deformation).
3. Conduct self-diagnosis using CONSULT-II and “AIR BAG” warning lamp. Refer to SRS-20, "
SRS Opera-
tion Check" for details. Ensure entire SRS operates properly.
WHEN SRS IS NOT ACTIVATED IN THE SIDE OR ROLLOVER COLLISION
1. Check the SRS components and the related parts using the following table.
- If the front seat back assembly is damaged, the front seat back assembly must be replaced.
2. Conduct self-diagnosis using CONSULT-II and “AIR BAG” warning lamp. Refer to SRS-20, "
SRS Opera-
tion Check" for details. Ensure entire SRS operates properly.
SRS INSPECTION (FOR SIDE AND ROLLOVER COLLISION)
Steering wheel 1. Visually check steering wheel for deformities.
2. Check harness (built into steering wheel) and connectors for damage, and terminals for deformities.
3. Install driver air bag module into the steering wheel to check fit and alignment with the wheel.
4. Check steering wheel for excessive free play.
5. If no damage is found, reinstall.
6. If damaged—REPLACE.
Spiral cable If the driver front air
bag has deployed:
REPLACE the spiral
cable.If the driver front air bag has not deployed:
1. Visually check spiral cable and combination switch for damage.
2. Check connectors and protective tape for damage.
3. Check steering wheel for noise, binding or heavy operation.
4. If no damage is found, reinstall.
5. If damaged—REPLACE.
Occupant classifica-
tion system (Passen-
ger seat)1. Remove passenger seat.
2. Check control unit case for dents, cracks of deformities.
3. Check connectors and pressure sensor tube for damage, and terminals for deformities.
4. Check seat frame and cushion pan for dents or deformities.
5. If no damage is found, reinstall seat with new fasteners.
6. If damaged — REPLACE seat cushion assembly with new fasteners.
Harness and connec-
tors1. Check connectors for poor connection, damage, and terminals for deformities.
2. Check harness for binding, chafing, cuts, or deformities.
3. If no damage is found, reinstall the harness and connectors.
4. If damaged—REPLACE the damaged harness. Do not attempt to repair, splice or modify any SRS har-
ness.
Instrument panel If the passenger front
air bag has deployed:
REPLACE the instru-
ment panel assembly.If the passenger front air bag has NOT deployed:
1. Visually check instrument panel for damage.
2. If no damage is found, reinstall the instrument panel.
3. If damaged—REPLACE the instrument panel. Part SRS is activated SRS is NOT activated

TF-18
< SERVICE INFORMATION >
ALL-MODE 4WD SYSTEM
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 oper-
ating 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 different
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.
4WD WARNING LAMP
Turns ON or FLASH when there is a malfunction in 4WD system.
Also turns ON when ignition switch is turned ON, for purpose of lamp check. Turns OFF for approximately 1
second after the engine starts if system is normal.
4WD Warning Lamp Indication
Condition Content 4WD warning lamp
During self-diagnosis Indicates the malfunction position by number of flickers. Flickers at malfunction mode.
Lamp check*Checks the lamp by turning ON during engine starting. After
engine starts, it turns OFF if there are no malfunctions.ON
Malfunction in 4WD system*Turns ON to indicate malfunction. When ignition switch is
turned to “OFF” or the malfunction is corrected, it turns OFF.ON
When vehicle is driven with different
diameters of front and rear tiresFlickers once every 2 seconds.
Turns OFF when ignition switch is “OFF”.Flickers once every 2 sec-
onds.

TF-34
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Trouble Diagnosis Chart by Symptom
INFOID:0000000003532525
If 4WD warning lamp turns ON, perform self-diagnosis. Refer to TF-48, "Self-Diagnosis Procedure" .
NOTE:
• Light tight-corner braking symptom may occur depending on driving conditions in AUTO mode. This is not a
malfunction.
Symptom Condition Check item Reference page
4WD shift indicator lamp and 4LO indicator
lamp do not turn ON
(4WD shift indicator lamp and 4LO indicator
lamp check)Ignition switch: ONPower supply and ground for transfer
control unit
TF-102
Transfer shut off relay
Combination meter
4WD warning lamp does not turn ON
(4WD warning lamp check)Ignition switch: ONPower supply and ground for transfer
control unit
TF-104
Transfer shut off relay
Combination meter
4WD shift indicator lamp or 4LO indicator
lamp does not changeEngine running4WD shift switch
TF-107
Wait detection switch
Neutral-4LO switch
ATP switch
2-4WD solenoid
Transfer control device
Actuator motor
Actuator position switch
Transfer inner parts
ATP warning lamp turns ON Engine runningCAN communication line
TF-109
4WD shift switch
PNP switch signal
ATP switch
Combination meter
Transfer inner parts
4LO indicator lamp repeats flashing Engine runningWait detection switch
TF-110
Neutral-4LO switch
Transfer inner parts
4WD warning lamp flashes rapidly (2 times/
second)While drivingTransfer fluid temperature
TF-111
Tire size is different between front and
rear of vehicle
4WD warning lamp flashes slowly
(1 time/2 seconds)While drivingTire size is different between front and
rear of vehicle.
TF-112
Transfer fluid temperature
Clutch pressure switch
Heavy tight-corner braking symptom occurs
(See NOTE.)• While driving
•AUTO mode
• Steering wheel is
turned fully to either
sideCAN communication line
TF-113
4WD shift switch
Accelerator pedal position signal
Clutch pressure solenoid
Transfer inner parts
4WD system does not operate While driving4WD shift switch
TF-114
Clutch pressure switch
Transfer inner parts

TROUBLE DIAGNOSIS
TF-35
< SERVICE INFORMATION >
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• Heavy tight-corner braking symptom occurs when vehicle is driven in the following conditions: 4WD shift
switch is "4H" or "4LO", steering wheel is turned fully to either side.
Transfer Control Unit Input/Output Signal Reference ValueINFOID:0000000003532526
TRANSFER CONTROL UNIT INSPECTION TABLE
Specifications with CONSULT-II
Monitored item [Unit] Content Condition Display value
VHCL/S SEN·FR [km/h]
or [mph]Front wheel speedVehicle stopped 0 km/h (0 MPH)
Vehicle running
CAUTION:
Check air pressure of tire under standard condition.Approximately
equal to the indica-
tion on speedome-
ter (Inside of
±10%)
VHCL/S SEN·RR [km/h]
or [mph]Rear wheel speedVehicle stopped 0 km/h (0 MPH)
Vehicle running
CAUTION:
Check air pressure of tire under standard condition.Approximately
equal to the indica-
tion on speedome-
ter (Inside of
±10%)
ENGINE SPEED [rpm] Engine speedEngine stopped
(Engine speed: Less than 400 rpm)0 rpm
Engine running
(Engine speed: 400 rpm or more)Approximately
equal to the indica-
tion on tachometer
THRTL POS SEN [V]Accelerator pedal posi-
tion (APP) sensor signal
voltageAccelerator pedal: Release Approx. 0.5V
Accelerator pedal: Fully depressed Approx. 4.0V
FLUID TEMP SE [V]Transfer fluid tempera-
ture signal voltageTransfer fluid temperature approx. 20 - 80°C (68 - 176°F) Approx. 1.1 - 0.3V
BATTERY VOLT [V]Power supply voltage for
transfer control unitIgnition switch: ON Battery voltage
2WD SWITCH [ON/OFF]Input condition from 4WD
shift switch4WD shift switch: 2WD ON
4WD shift switch: AUTO, 4H or 4LO OFF
AUTO SWITCH [ON/
OFF]Input condition from 4WD
shift switch4WD shift switch: AUTO ON
4WD shift switch: 2WD, 4H or 4LO OFF
LOCK SWITCH [ON/
OFF]Input condition from 4WD
shift switch4WD shift switch: 4H ON
4WD shift switch: 2WD, AUTO or 4LO OFF
4L SWITCH [ON/OFF]Input condition from 4WD
shift switch4WD shift switch: 4LO ON
4WD shift switch: 2WD, AUTO or 4H OFF
N POSI SW TF [ON/
OFF]Condition of neutral-4LO
switch• Vehicle stopped
• Engine running
• A/T selector lever “N” posi-
tion
• Brake pedal depressed4WD shift switch: 2WD,
AUTO or 4HOFF
4WD shift switch: 4H to
4LO (While actuator mo-
tor is operating.)OFF → ON
4WD shift switch: 4LO to
4H (While actuator motor
is operating.)ON → OFF
4WD shift switch: 4LO ON