2004 INFINITI QX56 oil temperature

CHASSIS AND BODY MAINTENANCE
MA-29
C
D
E
F
G
H
I
J
K
MA
B
MA
Revision: August 20072004 QX56
Checking Power Steering Fluid and LinesELS0010U
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-10, "Fluids and Lubricants" .
CHECKING LINES

Check lines for improper attachment, leaks, cracks, damage,
loose connections, chafing and deterioration.
Checking Axle and Suspension PartsELS0010V
FRONT AND REAR AXLE AND SUSPENSION PARTS
Check front and rear axle and suspension parts for excessive play, cracks, wear or other damage.

Shake each wheel to check for excessive play.

Rotate each wheel to check for abnormal noise.

Check axle and suspension nuts and bolts for looseness.

Check the strut and shock absorber for oil leakage or other damage.

Check suspension ball joints for grease leakage and ball joint dust cover for cracks or other damage.
DRIVE SHAFT
Check the boots and drive shaft for cracks, wear, damage, and
grease leakage.
LGIA0021E
SGIA0506E
SM A52 5A
SFA90 1

PS-6
POWER STEERING FLUID
Revision: August 20072004 QX56
POWER STEERING FLUIDPFP:KLF20
Checking Fluid LevelEGS000MN
Check fluid level, 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-10, "
RECOMMENDED FLUIDS AND LUBRI-
CANTS" .
Checking Fluid LeakageEGS000MO
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-26, "
POWER STEERING OIL
PUMP" .
6. Check steering gear boots for accumulation of fluid indicating a leak from the steering gear.
Air Bleeding Hydraulic SystemEG S0 0 0MP
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

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

SRS-46
DRIVER AIR BAG MODULE
Revision: August 20072004 QX56

Always place air bag module with pad side facing upward.

Do not insert any foreign objects (screwdriver, etc.) into air
bag module or harness connectors.

Do not disassemble air bag module.

Do not use old bolts after removal; replace with new bolts.

Do not expose the air bag module to temperatures exceed-
ing 90°C (194°F).

Replace the air bag module if it has been dropped or sus-
tained an impact.

Do not allow oil, grease or water to come in contact with the
air bag module.
INSTALLATION
To install, reverse the removal procedure.

If driver air bag module is being replaced due to deployment, spiral cable must also be replaced. Refer to
SRS-47, "
SPIRAL CABLE" .

For removal/installation of the direct-connect SRS connectors, refer to SRS-7, "Direct-connect SRS Com-
ponent Connectors" .

After the work is completed, perform self-diagnosis to check that no malfunction is detected. Refer to
SRS-20, "
SRS Operation Check" .
LHIA0052E
SBF 8 14 E

SIDE CURTAIN AIR BAG MODULE
SRS-53
C
D
E
F
G
I
J
K
L
MA
B
SRS
Revision: August 20072004 QX56
SIDE CURTAIN AIR BAG MODULEPFP:985P0
Removal and InstallationEHS0 00 W P
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-37, "
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.
INSTALLATION
To install, reverse the removal procedure.

For removal/installation of the direct-connect SRS connectors, refer to SRS-7, "Direct-connect SRS Com-
ponent Connectors" .
LHIA0079E
SBF 8 14 E

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

TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
TF-55
C
E
F
G
H
I
J
K
L
MA
B
TF
Revision: August 20072004 QX56
TROUBLE DIAGNOSIS — GENERAL DESCRIPTIONPFP:00000
Transfer Control Unit Terminals and Reference ValueEDS00181
TRANSFER CONTROL UNIT HARNESS CONNECTOR LAYOUT
TRANSFER CONTROL UNIT INSPECTION TABLE
LDIA0066E
Te r m i n a l
No.Item ConditionJudgement standard
(Approx.)
12-4WD shift solenoid
valve &4WD shift switch is set to 2WD posi-
tion.Less than 1V
4WD shift switch is set to any posi-
tion other than 2WD.Battery voltage
24WD shift indicator lamp
(2WD)Lamp lights while system is operating
properly.Less than 1V
&2WD indicator lamp does not come
on.Battery voltage
3Ground — —
4 Transfer shift relay (High)While actuator is operating (4H →
4LO)Battery voltage
Actuator does not operate. Less than 1V
5 4WD warning lampLamp comes ON (when engine is
stopped).
(Fail-safe condition appears on dis-
play, engine is stopped, actuator
position detection switch is inopera-
tive, oil temperature is too high and/
or tires of different size are installed.)Less than 1V
Except above Battery voltage
6Ground — — —
7CAN-H — — —
8CAN-L — — —
9 4WD shift switch (2WD)
&4WD shift switch is set to 2WD posi-
tion.Battery voltage
4WD shift switch is set to any posi-
tion other than 2WD.Less than 1V
10 Transfer dropping resistor4WD shift switch is set to AUTO posi-
tion.4 - 14V
4WD shift switch is set to any posi-
tion other than 2WD.Less than 1V