2004 INFINITI QX56 oil pressure

PS-26
POWER STEERING OIL PUMP
Revision: August 20072004 QX56
POWER STEERING OIL PUMPPFP:49110
On-Vehicle Inspection and ServiceEGS000MW
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 InstallationEG S0 0 0MX
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

POWER STEERING OIL PUMP
PS-27
C
D
E
F
H
I
J
K
L
MA
B
PS
Revision: August 20072004 QX56
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

HYDRAULIC LINE
PS-31
C
D
E
F
H
I
J
K
L
MA
B
PS
Revision: August 20072004 QX56
HYDRAULIC LINEPFP:49721
Removal and InstallationEGS000MZ
Refer to the following illustration for hydralic line removal.
1. Reservoir tank 2. Suction hose 3. High pressure hose
4. Oil cooler 5. Steering gear assembly 6. Reservoir tank bracket
7. Eye bolt
WGIA0096E

SERVICE DATA AND SPECIFICATIONS (SDS)
PS-35
C
D
E
F
H
I
J
K
L
MA
B
PS
Revision: August 20072004 QX56
Steering GearEGS000NI
Oil PumpEG S0 0 0NJ
Steering FluidEGS000NK
Steering gear modelPR26AM
Rack neutral position, dimension “L” (rack stroke) 85.5 mm (3.36 in)
Rack sliding forceAt the neutral point:
Range within ± 11.5 mm
(±0.453 in) from the neutral
position
(in power ON)Area average value 147 − 211 N (14.99 − 21.52 kg, 33.1 − 47.52 lb)
Allowable variation 98 N (10 kg, 22 lb) or less
Whole area (in power OFF)Peak value 294 N (30.0 kg, 66 lb) or less
Allowable variation 147 N (16 kg, 35 lb) or less
STC0034D
Relief oil pressure
9.0 − 9.8 mPa (91.77 − 99.93 kg/cm2 , 1305.34 − 1421.37 psi)
Fluid capacity
Approx. 1.0 (1-1/8 US qt, 7/8 Imp qt)

REAR SUSPENSION MEMBER
RSU-31
C
D
F
G
H
I
J
K
L
MA
B
RSU
Revision: August 20072004 QX56
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.
1. Seat belt latch anchor 2. Stabilizer bar bushing 3. Stabilizer bar clamp
4. Stabilizer bar 5. Connecting rod 6. Front lower link
7. Knuckle 8. Bushing 9. Rear lower link
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
LEIA0072E
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)

REAR LOWER LINK & COIL SPRING
RSU-39
C
D
F
G
H
I
J
K
L
MA
B
RSU
Revision: August 20072004 QX56
REAR LOWER LINK & COIL SPRINGPFP:551B0
Removal and Installation EES0011P
REMOVAL
1. Remove the wheel and tire assembly using power tool. Refer to WT-6, "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.
WAR NIN G:
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

SC-28
SERVICE DATA AND SPECIFICATIONS (SDS)
Revision: August 20072004 QX56
SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
BatteryEKS0079J
StarterEKS0079K
GeneratorEKS0079L
Typ eGr. 27
Capacity (20 HR) minimum 12V - 80AH
Cold cranking current A
(For reference value)710
ApplicationAll models
ManufacturerMitsubishi
M002T85571ZCKD
Ty peReduction gear type
System voltage 12V
No-loadTerminal voltage 11V
Current Less than 145A
Revolution More than 3,300 rpm
Minimum diameter of commutator 31.4 mm (1.236 in)
Minimum length of brush 11.0 mm (0.433 in)
Brush spring tension 26.7 - 36.1 N (2.72 - 3.68 kg, 5.93 - 8.02 lb)
Clearance between pinion front edge and
pinion stopper0.5 - 2.0 mm (0.020 - 0.079 in)
Ty peLR1130-701
Hitachi
Nominal rating12V - 130A
Ground polarityNegative
Minimum revolution under no-load (When 13.5 volts is applied) 1,200 rpm
Hot output current (When 13.5 volts is applied)More than 78A/1,800 rpm
More than 108A/2,500 rpm
More than 130A/5,000 rpm
Regulated output voltage 14.1 - 14.7V @ 25°C
Minimum length of brush 6 mm (0.24 in)
Brush spring pressure 1.0 - 3.432 N (0.102 - 0.3501 kg, 0.22 - 0.7715 lbs)
Slip ring minimum outer diameter 26 mm (1.02 in)
Rotor (Field coil) resistance 2.1 ohms

TF-2Revision: August 20072004 QX56 SWITCH ..................................................................... 62
Diagnostic Procedure ............................................. 62
TRANSFER MOTOR AND TRANSFER MOTOR
RELAY ....................................................................... 64
Diagnostic Procedure ............................................. 64
TRANSFER FLUID TEMPERATURE SENSOR ....... 66
Diagnostic Procedure ............................................. 66
ATP SWITCH, WAIT DETECTION SWITCH AND
NEUTRAL-4LO SWITCH .......................................... 69
Diagnostic Procedure ............................................. 69
CLUTCH PRESSURE SWITCH ................................ 72
Diagnostic Procedure ............................................. 72
LINE PRESSURE SWITCH ....................................... 74
Diagnostic Procedure ............................................. 74
DATA ERASE/DISPLAY ............................................ 76
Diagnostic Procedure ............................................. 76
SHIFT ACTUATOR ................................................... 77
Diagnostic Procedure ............................................. 77
SHIFT ACTUATOR POSITION SWITCH .................. 80
Diagnostic Procedure ............................................. 80
SHIFT ACTUATOR CIRCUIT .................................... 82
Diagnostic Procedure ............................................. 82
TROUBLE DIAGNOSES FOR SYMPTOMS ............. 85
Symptom 1. 4WD Shift Indicator Lamp Does Not
Turn ON (Although the ignition switch is turned ON,
all the 4WD indicator lamps do not turn ON for 1
second) ................................................................... 85
Symptom 2. 4WD Warning Lamp Does Not Turn ON
(Although the ignition switch is turned ON, the 4WD
warning lamp does not turn ON) ............................. 87
Symptom 3. 4WD Shift Indicator Lamp Does Not
Turn OFF (When 4WD shift switch is set from 4H
to 4LO, all the 4WD shift indicator lamps do not turn
off) ........................................................................... 88
Symptom 4. ATP Warning Lamp Does Not Turn ON
(When 4WD shift switch is set from 4H to 4LO with
the A/T selector lever in P position, the ATP warning
lamp does not turn on) ............................................ 89
Symptom 5. 4LO Indicator Lamp Does Not Turn ON
(When 4WD shift switch is set from 4H to 4LO posi-
tion, 4LO indicator lamp does not turn ON) ............ 90
Symptom 6. 4WD Shift Indicator Lamp Does Not
Indicate “LOCK” (When 4WD shift switch is set to
“4H”, 4WD shift indicator lamp does not indicate
“LOCK”) .................................................................. 91
Symptom 7. 4WD Shift Indicator Lamp Repeats
Flickering (4WD Shift Indicator Lamp Keeps Flick-
ering) ...................................................................... 92
Symptom 8. Tight Corner Braking Symptom (Tight
Corner Braking Symptom Occurs-Hydraulic Sys-
tem Failure) ............................................................ 93
Symptom 9. 4WD System Does Not Operate (The
Vehicle Cannot Be Put Into 4WD Mode-Hydraulic
System Failure) ...................................................... 94
Component Inspection ............................................ 95
4WD SHIFT SWITCH .......................................... 95
2-4WD SHIFT SOLENOID VALVE AND TRANS-
FER FLUID TEMPERATURE SENSOR .............. 95
4WD SOLENOID VALVE, CLUTCH PRESSURE SWITCH AND LINE PRESSURE SWITCH .........95
TRANSFER DROPPING RESISTOR ..................96
ATP SWITCH, NEUTRAL-4LO SWITCH AND
WAIT DETECTION SWITCH ...............................96
TRANSFER MOTOR ...........................................96
TRANSFER MOTOR RELAY ...............................97
TRANSFER SHIFT RELAY (HIGH & LOW) .........97
ACTUATOR AND ACTUATOR POSITION
SWITCH ...............................................................97
TRANSFER CONTROL UNIT ...................................98
Removal and Installation .........................................98
REMOVAL ............................................................98
INSTALLATION ....................................................98
FRONT OIL SEAL .....................................................99
Removal and Installation .........................................99
REMOVAL ............................................................99
INSTALLATION .................................................. 100
REAR OIL SEAL ..................................................... 101
Removal and Installation ....................................... 101
REMOVAL .......................................................... 101
INSTALLATION .................................................. 101
SIDE OIL SEAL ....................................................... 103
Removal and Installation ....................................... 103
REMOVAL .......................................................... 103
INSTALLATION .................................................. 103
TRANSFER CONTROL DEVICE ............................ 104
Removal and Installation ....................................... 104
AIR BREATHER HOSE ........................................... 105
Removal and Installation ....................................... 105
TRANSFER MOTOR ............................................... 106
Removal and Installation ....................................... 106
REMOVAL .......................................................... 106
INSTALLATION ..................................................... 106
TRANSFER OIL FILTER ......................................... 107
Removal and Installation ....................................... 107
REMOVAL .......................................................... 107
INSTALLATION .................................................. 107
REMOVAL AND INSTALLATION ............................ 109
Removal ................................................................ 109
Installation ............................................................. 109
OVERHAUL .............................................................110
Transfer Components ...........................................110
REAR CASE ............................................................112
Disassembly ..........................................................112
CENTER CASE .......................................................113
Disassembly ..........................................................113
FRONT DRIVE SHAFT AND DRIVE CHAIN .....115
MAINSHAFT AND CLUTCH DRUM ..................116
CLUTCH PISTON ..............................................118
CONTROL VALVE .............................................119
MAINSHAFT REAR BEARING .......................... 122
MAIN OIL PUMP ................................................ 122
SUB OIL PUMP ................................................. 123
OIL FILTER ........................................................ 124
FRONT CASE .......................................................... 125
Disassembly .......................................................... 125
SHIFT ROD COMPONENTS ............................. 125
PLANETARY CARRIER, SUN GEAR AND
INTERNAL GEAR .............................................. 127