2004 INFINITI QX56 sensor

POWER STEERING OIL PUMP
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Disassembly and AssemblyEGS000MY
INSPECTION BEFORE DISASSEMBLY
Disassemble power steering oil pump only if the following conditions are found.

Oil leakage from oil pump

Deformed or damaged pulley

Poor performance
DISASSEMBLY
CAUTION:
When retaining drive shaft in a vise, always use copper or aluminum plates between vise and shaft.
NOTE:
Mount the oil pump in a vise as needed.
1. Unscrew three bracket bolts and remove bracket from rear cover.
2. Unscrew four rear cover bolts and remove rear cover from body assembly.
3. Remove gasket from body assembly.
4. Remove lock pin, cartridge and side plate from body assembly.
5. Remove pulley from drive shaft assembly.
1. Bracket 2. Rear cover 3. Gasket
4. Lock pin 5. Cam ring 6. Rotor
7. Vane 8. Cartridge 9. Side plate
10. O-ring 11. Body assembly 12. Oil seal
13. Drive shaft assembly 14. Snap ring 15. Pulley
16. Spring washer 17. Flow control valve 18. Pressure sensor
19. Connector bolt 20. Copper washer 21. Bracket
22. Suction pipe 23. O-ring
WGIA0076E

WHEEL HUB
RAX-5
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Revision: August 20072004 QX56
WHEEL HUBPFP:43202
On-Vehicle Inspection and ServiceEDS001AT
Inspect the components for any looseness or back lash. Inspect each component for any excessive wear or
damage. Replace any components as necessary.
WHEEL BEARING INSPECTION

Move the wheel hub and bearing assembly in the axial direction by hand to check the axial end play.
Check that the axial end play is with specification. Replace the wheel hub and bearing assembly as nec-
essary.

Rotate the wheel hub and bearing assembly to check that there are no unusual noises or other abnormal
conditions. Replace the wheel hub and bearing assembly as necessary.
Removal and InstallationEDS001AU
Rear Wheel Hub and Bearing Assembly
NOTE:
The rear ABS sensor is routed through the back of the rear backing plate and into the side of the wheel hub
and bearing assembly. It is necessary to remove the wheel hub and bearing assembly to remove the rear ABS
sensor.
REMOVAL
1. Remove the wheel and tire using power tool.
2. Remove the rear brake caliper, without disconnecting the hydraulic hose, using power tool. Reposition the
rear brake caliper aside using suitable wire. Refer to BR-28, "
Removal and Installation of Brake Caliper
Assembly and Disc Rotor" .
NOTE:

Do not depress the brake pedal while the brake caliper is removed.
3. Remove the rear disc rotor.Axial end play : 0 mm (0 in)
WDIA0300E
1. Back plate 2. Rear ABS sensor 3. Wheel hub and bearing assembly
4. Wheel stud 5. Rear disc rotor 6. Cotter pin
⇐: Vehicle front

RAX-6
WHEEL HUB
Revision: August 20072004 QX56
4. Remove the cotter pin, then remove the nut from the drive shaft
using power tool.

Discard the cotter pin, use a new one for installation.
5. Remove the drive shaft. Refer to RAX-7, "
Removal and Installa-
tion" .
6. Remove the four wheel hub and bearing assembly bolts using power tool.

Discard the four wheel hub and bearing assembly bolts, use new ones for installation.
7. Pull out the wheel hub and bearing assembly for access to
remove the rear ABS sensor from the wheel hub and bearing
assembly as shown.

Inspect the ABS sensor O-ring, replace the ABS sensor
assembly if damaged.

Clean the ABS sensor hole and mounting surface with a suit-
able brake cleaner and a clean lint-free shop rag. Be careful
that dirt and debris do not enter the axle bearing area.

Apply a coat of suitable grease to the ABS sensor O-ring and
mounting hole.
CAUTION:
Do not pull on the ABS harness.
8. Remove the wheel hub and bearing assembly.
INSTALLATION
Installation is in the reverse order of removal.

Apply grease 44003 7S000CM to contact surface (A) between
wheel hub and bearing assembly and drive shaft as shown. Use
sufficient grease to completely coat contact area.

Inspect the ABS sensor O-ring, replace the ABS sensor assem-
bly if damaged.

Clean the ABS sensor hole and mounting surface with a suitable
brake cleaner and a clean lint-free shop rag. Be careful that dirt
and debris do not enter the axle bearing area.

Apply a coat of suitable grease to the ABS sensor O-ring and
mounting hole.

Use a new cotter pin for installation.

Use new wheel hub and bearing assembly bolts for installation.
LDIA0050E
LDIA0052E
WDIA0299E

RSU-1
REAR SUSPENSION
E SUSPENSION
CONTENTS
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SECTION RSU
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RSU
Revision: August 20072004 QX56 PRECAUTIONS .......................................................... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Precautions for Rear Suspension ............................ 3
Wiring Diagrams and Trouble Diagnosis .................. 3
PREPARATION ........................................................... 4
Commercial Service Tools ........................................ 4
NOISE, VIBRATION, AND HARSHNESS (NVH)
TROUBLESHOOTING ................................................ 5
NVH Troubleshooting Chart ..................................... 5
CAN COMMUNICATION ............................................ 6
System Description .................................................. 6
TROUBLE DIAGNOSIS .............................................. 7
How to Perform Trouble Diagnoses for Quick and
Accurate Repair ....................................................... 7
INTRODUCTION ................................................... 7
CLARIFY CONCERN ............................................ 7
WORK FLOW ........................................................ 8
Component Parts and Harness Connector Location ..... 9
Wiring Diagram — A/SUSP — ............................... 10
Basic Inspection ..................................................... 12
AIR HOSES ......................................................... 12
POWER SYSTEM TERMINAL LOOSENESS
AND BATTERY INSPECTION ............................ 12
CK SUSP INDICATOR LAMP INSPECTION ...... 12
CK SUSP Indicator Lamp Timing ........................... 12
Control Unit Input/Output Signal Standard ............. 12
CONSULT-II Function (AIR LEVELIZER) ............... 13
CONSULT-II OPERATION .................................. 13
WORK SUPPORT ............................................... 14
SELF-DIAGNOSIS .............................................. 14
DATA MONITOR ................................................. 15
ACTIVE TEST ..................................................... 16
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC
ITEMS ....................................................................... 17
Height Sensor System Inspection .......................... 17
Exhaust Valve Solenoid System Inspection ........... 19
Compressor Motor, Compressor Motor Relay and Circuit Inspection .................................................... 20
TROUBLE DIAGNOSES FOR SYMPTOMS ............ 23
Load Leveling Rear Air Suspension System Does
Not Operate ............................................................ 23
CK SUSP Indicator Lamp Stays On When Ignition
Switch Is Turned On ............................................... 24
REAR SUSPENSION ASSEMBLY ........................... 25
Components ........................................................... 25
On-Vehicle Inspection and Service ......................... 26
SHOCK ABSORBER INSPECTION .................... 26
Wheel Alignment Inspection ................................... 27
PRELIMINARY INSPECTION ............................. 27
GENERAL INFORMATION AND RECOMMEN-
DATIONS ............................................................. 27
THE ALIGNMENT PROCESS ............................. 28
CAMBER ............................................................. 28
TOE-IN ................................................................ 28
REAR SUSPENSION MEMBER ............................... 30
Removal and Installation ........................................ 30
REMOVAL ........................................................... 31
INSPECTION AFTER REMOVAL ....................... 32
INSTALLATION ................................................... 33
SHOCK ABSORBER ................................................ 34
Removal and Installation ........................................ 34
REMOVAL ........................................................... 34
INSTALLATION ................................................... 34
INSPECTION AFTER INSTALLATION ................ 34
SUSPENSION ARM .................................................. 35
Removal and Installation ........................................ 35
REMOVAL ........................................................... 35
INSPECTION AFTER REMOVAL ....................... 35
INSTALLATION ................................................... 36
FRONT LOWER LINK .............................................. 37
Removal and Installation ........................................ 37
REMOVAL ........................................................... 37
INSPECTION AFTER REMOVAL ....................... 37
INSTALLATION ................................................... 38

RSU-2Revision: August 20072004 QX56 REAR LOWER LINK & COIL SPRING ..................... 39
Removal and Installation ........................................ 39
REMOVAL ........................................................... 39
INSPECTION AFTER REMOVAL ........................ 40
INSTALLATION .................................................... 40
STABILIZER BAR ..................................................... 41
Removal and Installation ........................................ 41
REMOVAL ........................................................... 41
INSTALLATION .................................................... 41
Inspection ............................................................... 41
REAR LOAD LEVELING AIR SUSPENSION COM-
PRESSOR ASSEMBLY ............................................ 42
Removal and Installation ........................................ 42
REMOVAL ........................................................... 42
INSTALLATION .................................................... 43HEIGHT SENSOR .....................................................44
Removal and Installation .........................................44
REMOVAL ............................................................44
INSTALLATION ....................................................45
CONTROL UNIT ........................................................46
Removal and Installation .........................................46
REMOVAL ............................................................46
INSTALLATION ....................................................46
Initialization Procedure ............................................46
SERVICE DATA AND SPECIFICATIONS (SDS) ......47
Wheel Alignment .....................................................47
Ball Joint .................................................................47
Wheelarch Height (Unladen*
1 ) ...............................48

TROUBLE DIAGNOSIS
RSU-7
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Revision: August 20072004 QX56
TROUBLE DIAGNOSISPFP:00000
How to Perform Trouble Diagnoses for Quick and Accurate RepairEES00113
INTRODUCTION
The rear load leveling air suspension system uses an electronic con-
trol unit to control major functions. The control unit accepts input sig-
nals from the height sensor and controls compressor and exhaust
valve operation.
It is much more difficult to diagnose a rear load leveling air suspen-
sion system problem that occurs intermittently rather than continu-
ously. Most intermittent problems are caused by poor electrical
connections or faulty wiring. In this case, careful checking of suspi-
cious circuits may help prevent the replacement of good parts.
Before undertaking actual checks, take just a few minutes to talk with
a customer who approaches with an air suspension system com-
plaint. The customer is a very good source of information on such
problems, especially intermittent ones. Through discussion with the
customer, find out what symptoms are present and under what con-
ditions they occur.
Start your diagnosis by looking for basic mechanical problems first.
This is one of the best ways to troubleshoot concerns on an air sus-
pension system equipped vehicle. Also check related Service Bulle-
tins for information.
CLARIFY CONCERN

A customer's description of a vehicle concern may vary depend-
ing on the individual. It is important to clarify the customer's con-
cern.

Ask the customer about what symptoms are present under what
conditions. Use this information to reproduce the symptom.
SEF 2 33 G
SEF 2 34 G
SBR3 39 B

RSU-12
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Basic InspectionEES00116
AIR HOSES
1. Check for pinched or damaged air hoses between the suspension air reservoir and each load leveling rear
air suspension shock absorber. Reposition, repair or replace hoses as necessary.
2. Check the air hose connections at the suspension air reservoir and at the shock absorbers for leaks. If
connections are leaking, repair or replace hoses as necessary.
POWER SYSTEM TERMINAL LOOSENESS AND BATTERY INSPECTION
Make sure the battery positive cable, negative cable and ground connection are not loose. In addition, make
sure the battery is sufficiently charged.
CK SUSP INDICATOR LAMP INSPECTION
1. Make sure the CK SUSP indicator lamp turns on for approximately 2 seconds when the ignition switch is
turned ON. If it does not, check the combination meter. Refer to DI-5, "
COMBINATION METERS" .
2. Make sure the lamp turns off approximately 2 seconds after the ignition switch is turned ON. If the lamp
does not turn off, conduct self-diagnosis of the suspension control unit.
3. After conducting the self-diagnosis, be sure to erase the error memory. Refer to RSU-13, "
CONSULT-II
Function (AIR LEVELIZER)" .
CK SUSP Indicator Lamp TimingEES00117
X: ON
—: OFF
Control Unit Input/Output Signal StandardEES00118
( ): Wire colorConditionCK SUSP
indicator lampRemarks
Ignition switch OFF – –
Ignition switch ON X Turns off after approximately 2 seconds.
Te r m i n a l
Item ConditionVoltage (V)
(Approx.)
+–
1 (V)
GroundCompressor relay output
Ignition switch ON or STARTBattery voltage
3 (W) Height sensor signal input 0.2V - 4.8V
5 (R) Reference voltage 5V
6 (G/R) Ignition power
Battery voltage
7 (W/L) Battery power —
8 (G/W) Diagnostic K-line — —
9 (SB) Exhaust valve output Ignition switch ON or START Battery voltage
10 (BR) Warning lamp output — —
14 (L) Height sensor ground — —
15 (BR/W) Alternator L signal input Engine running —
16 (B) Suspension control unit ground — 0V

TROUBLE DIAGNOSIS
RSU-15
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RSU
Revision: August 20072004 QX56
CAUTION:
If the error memory is not erased, re-conduct the operation from step 7.
10. For the final inspection, start and run the vehicle for approximately 1 minute and confirm that the CK
SUSP indicator lamp is off.
Display Item List
DATA MONITOR
Operation Procedure
1. After turning OFF the ignition switch, connect CONSULT-II and the CONSULT-II CONVERTER to the data
link connector.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
2. Touch “START (NISSAN BASED VHCL)”, "AIR LEVELIZER", “DATA MONITOR” in order on the CON-
SULT-II screen.
If "AIR LEVELIZER" is not indicated, go to GI-39, "
CONSULT-II Data Link Connector (DLC) Circuit" .
CAUTION:
When “START (NISSAN BASED VHCL)” is touched immediately after starting the engine or turning
on the ignition switch, "AIR LEVELIZER" might not be displayed in the "SELECT SYSTEM" screen.
In this case, repeat the operation from step 2.
3. Return to the "SELECT MONITOR ITEM" screen, and touch "ALL SIGNALS" or "SELECTION FROM
MENU". Refer to the following information.
4. When “START” is touched, the data monitor screen is displayed.
Self-diagnostic item Malfunction detecting condition Check system
Vehicle height sensor
[C1801]Vehicle height sensor voltage is less than 0.2V or greater than
4.8V for more than 60 seconds.Refer to RSU-17, "
Height
Sensor System Inspection" .
Compressor relay
[C1802]1. Driving transistor for compressor relay is off and monitor volt-
age continues high level for more than 10 seconds.
2. Driving transistor for compressor relay is on and monitor volt-
age continues low level for more than 5 seconds.Refer to RSU-20, "
Compres-
sor Motor, Compressor
Motor Relay and Circuit
Inspection" .
Exhaust solenoid
[C1803]1. Driving transistor for exhaust solenoid is off and monitor volt-
age continues high level for more than 10 seconds.
2. Driving transistor for exhaust solenoid is on and monitor volt-
age continues low level for more than 5 seconds.Refer to RSU-19, "
Exhaust
Valve Solenoid System
Inspection" .
Vehicle height adjusting trouble
(compressor)
[C1804]Continuous compressor relay ON time is more than 120 sec-
onds.Refer to RSU-20, "
Compres-
sor Motor, Compressor
Motor Relay and Circuit
Inspection" .
Vehicle height adjusting trouble
(exhaust solenoid)
[C1805]Continuous exhaust solenoid ON time is more than 120 seconds.Refer to RSU-19, "
Exhaust
Valve Solenoid System
Inspection" .
Vehicle height sensor locking trou-
ble
[C1806]Output sensor voltage variation ±0.02V is more than 100 hour
when vehicle height range is normal.Refer to RSU-17, "
Height
Sensor System Inspection" .
Sensor 5V trouble
[C1807]Sensor reference voltage is less than 0.8V or more than 6V for
20 seconds.Refer to RSU-17, "
Height
Sensor System Inspection" .
Integral time trouble by supplying
air
[C1808]Integral discontinuous time on the compressor is more than 180
seconds.Refer to RSU-20, "
Compres-
sor Motor, Compressor
Motor Relay and Circuit
Inspection" .