suspension INFINITI QX56 2007 Factory Repair Manual

REAR LOAD LEVELING AIR SUSPENSION COMPRESSOR ASSEMBLY
RSU-39
< SERVICE INFORMATION >
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D
F
G
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B
RSU
N
O
P
5. Remove the four bolts that mount the rear load leveling air sus-
pension compressor assembly to the underbody.
INSTALLATION
Installation is in the reverse order of removal.
• 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.
LEIA0090E
LEIA0078E

RSU-40
< SERVICE INFORMATION >
HEIGHT SENSOR
HEIGHT SENSOR
Removal and InstallationINFOID:0000000003532679
Rear Load Leveling Air Suspension System
REMOVAL
1. Use CONSULT-II “EXHAUST SOLENOID” active test to release the air pressure from the rear load level-
ing air suspension system.
2. Disconnect the electrical connector for the height sensor.
3. Remove the two height sensor bolts and height sensor arm
bracket bolt.
4. Remove the height sensor.
INSTALLATION
Installation is in the reverse order of removal.
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
⇐Front
LEIA0080E

RSU-42
< SERVICE INFORMATION >
CONTROL UNIT
CONTROL UNIT
Removal and InstallationINFOID:0000000003532680
REMOVAL
1. Remove the rear LH interior trim panel. Refer to EI-34 .
2. Disconnect the battery negative terminal.
3. Disconnect the suspension control unit electrical connector.
4. Remove the two bolts and remove the suspension control unit.
INSTALLATION
Installation is in the reverse order of removal.
Initialization ProcedureINFOID:0000000003532681
1. If control unit has been replaced, proceed to step 2. If control unit has not been replaced, use CONSULT-
II “CLEAR HEIGHT INI” work support function to clear initialization flag and value. The CK SUSP warning
lamp should illuminate. Using CONSULT-II “EXHAUST SOLENOID” active test, release the air pressure
from the rear load leveling air suspension system.
2. Roll vehicle forward and backward.
3. Use CONSULT-II “ADJUST HEIGHT INI” work support function to set initialization condition.
4. Confirm that CK SUSP warning lamp is OFF.
LEIA0100E
Suspension control unit bolts : 6 N·m (0.6 kg-m, 53 in-lb)

RSU-44
< SERVICE INFORMATION >
SERVICE DATA AND SPECIFICATIONS (SDS)
Wheelarch Height (Unladen*
1)INFOID:0000000003532684
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-42, "
Initialization Procedure" . Suspension type
Air leveling*
2
Applied model2WD 4WD
Front wheelarch height (Hf)913
(35.94)931
(36.65)
Rear wheelarch height (Hr)912
(35.91)932
(36.69)
LEIA0085E

WT-1
SUSPENSION
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SECTION WT
A
B
WT
N
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PCONTENTS
ROAD WHEELS & TIRES
SERVICE INFORMATION ............................2
PRECAUTIONS ...................................................2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ...................................................................
2
PREPARATION ...................................................3
Special Service Tool .................................................3
Commercial Service Tool ..........................................3
NOISE, VIBRATION AND HARSHNESS
(NVH) TROUBLESHOOTING .............................
4
NVH Troubleshooting Chart ......................................4
WHEEL ................................................................5
Inspection ..................................................................5
WHEEL AND TIRE ASSEMBLY .........................6
Balancing Wheels .....................................................6
Rotation .....................................................................7
LOW TIRE PRESSURE WARNING SYSTEM .....8
System Component ...................................................8
System Description ...................................................8
CAN COMMUNICATION ....................................10
System Description .................................................10
TROUBLE DIAGNOSIS .....................................11
Wiring Diagram- T/WARN - .....................................11
Terminal and Reference Value (BCM) ....................12
ID Registration Procedure .......................................12
Transmitter Wake Up Operation .............................14
CONSULT-II Function (BCM) ..................................15
Self-Diagnosis .........................................................15
How to Perform Trouble Diagnosis for Quick and
Accurate Repair .......................................................
17
Preliminary Check ...................................................18
Flash Code/Symptom Chart ....................................18
TROUBLE DIAGNOSIS FOR SELF-DIAG-
NOSTIC ITEMS .................................................
20
Data from Transmitter Not Being Received .............20
Transmitter Malfunction ...........................................20
Transmitter Pressure Malfunction ............................21
Vehicle Speed Signal ..............................................21
Ignition Signal ..........................................................22
TROUBLE DIAGNOSIS FOR SYMPTOMS ......23
Low Tire Pressure Warning Lamp Does Not Come
On When Ignition Switch Is Turned On ...................
23
Low Tire Pressure Warning Lamp Stays On When
Ignition Switch Is Turned On ...................................
23
Low Tire Pressure Warning Lamp Flashes When
Ignition Switch Is Turned On ...................................
24
Hazard Warning Lamps Flash When Ignition
Switch Is Turned On ................................................
25
"TIRE PRESSURE" Information in Display Unit
Does Not Exist .........................................................
25
ID Registration Cannot Be Completed ....................25
REMOVAL AND INSTALLATION .....................26
Transmitter (Pressure Sensor) ................................26
SERVICE DATA AND SPECIFICATIONS
(SDS) .................................................................
28
Road Wheel .............................................................28
Tire ..........................................................................28

WT-4
< SERVICE INFORMATION >
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting ChartINFOID:0000000003532688
Use the chart below to help you find the cause of the symptom. If necessary, repair or replace these parts.
×: ApplicableReference page
WT-5WT-6WT-28WT-7—
—
WT-28
FFD-6, "
NVH Troubleshooting Chart
" (FFD),
RFD-7, "
NVH Troubleshooting Chart
" (RFD)
FA X - 4 , "
NVH Troubleshooting Chart
" (FAX),
FSU-4, "
NVH Troubleshooting Chart
" (FSU)
RAX-4, "
NVH Troubleshooting Chart
" (RAX),
RSU-4, "
NVH Troubleshooting Chart
" (RSU)
Refer to TIRES in this chart.
Refer to ROAD WHEEL in this chart.
BR-4, "
NVH Troubleshooting Chart
"
PS-5, "
NVH Troubleshooting Chart
"
Possible cause and SUSPECTED PARTS
Out-of-round
Imbalance
Incorrect tire pressure
Uneven tire wear
Deformation or damage
Non-uniformity
Incorrect tire size
DIFFERENTIAL
FRONT AXLE AND FRONT SUSPENSION
REAR AXLE AND REAR SUSPENSION
TIRES
ROAD WHEEL
BRAKE
STEERING
SymptomTIRESNoise× ××××× × × × × ××
Shake× ×××× × × × × ××
Vibration××××××
Shimmy× ×××××× × × × ××
Shudder× ×××× × × × × ××
Poor quality ride or
handling× ×××× × × × ×
ROAD
WHEELNoise×× × ××× ×××
Shake×× × ×× ×××
Shimmy, shudder×× × ×× ×××
Poor quality ride or
handling×× × ×× ×

WHEEL
WT-5
< SERVICE INFORMATION >
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WT
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WHEEL
InspectionINFOID:0000000003532689
1. Check tires for wear and improper inflation.
2. Check wheels for deformation, cracks and other damage. If
deformed, remove wheel and check wheel runout.
a. Remove tire from wheel and mount wheel on a tire balance
machine.
b. Set dial indicator as shown. Refer to WT-28, "
Road Wheel" .
3. Check front wheel bearings for looseness.
4. Check front suspension for looseness.
SFA975B