2004 INFINITI QX56 service

SRS-4
PREPARATION
Revision: August 20072004 QX56
PREPARATIONPFP:00002
Special Service ToolsEHS000W2
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Commercial Service ToolsEHS000W3
Tool number
(Kent-Moore No.)
Tool nameDescription
—
(J-42057-UPD)
Air bag key set
Part of kit (J-42057)Removing and installing air bag lock
LRS210
Tool name
(Kent-Moore No.)Description
Steering wheel puller
(J-1859A)Removing steering wheel
Steering wheel puller legs
(J-42578)Removing steering wheel
LHIA0043E
LHIA0044E

SRS-8
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
TROUBLE DIAGNOSISPFP:00004
Trouble Diagnosis IntroductionEHS000WA
CAUTION:

Do not use electrical test equipment on any circuit related to the SRS unless instructed to do so in
this Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harness con-
nectors.

Do not attempt to repair, splice or modify SRS wiring harnesses. If a harness is damaged, replace
it with a new one.

Keep ground connections clean.
DIAGNOSIS FUNCTION
The SRS self-diagnosis results can be read by using “AIR BAG” warning lamp and/or CONSULT-II.
The User mode is exclusively prepared for the customer (driver). This mode warns the driver of a system mal-
function through the operation of the “AIR BAG” warning lamp.
The Diagnosis mode allows the technician to locate and inspect the malfunctioning part.
The mode applications for the “AIR BAG” warning lamp and CONSULT-II are as follows:
HOW TO PERFORM TROUBLE DIAGNOSES FOR QUICK AND ACCURATE REPAIR
A good understanding of the malfunction conditions can make troubleshooting faster and more accurate.
In general, each customer feels differently about a malfunction. It is important to fully understand the symp-
toms or conditions for a customer complaint.
Information From Customer
WHAT - Vehicle model
WHEN - Date, Frequencies
WHERE - Road conditions
HOW - Operating conditions, Symptoms
Preliminary Check
Check that the following parts are in good order.

Battery (Refer to SC-4, "How to Handle Battery" .)

Fuse (Refer to SRS-12, "Wiring Diagram — SRS —" .)

System component-to-harness connections
User mode Diagnosis mode Display type
“AIR BAG” warning lamp X X ON-OFF operation
CONSULT-II — X Monitoring

SRS-50
FRONT PASSENGER AIR BAG MODULE
Revision: August 20072004 QX56
FRONT PASSENGER AIR BAG MODULEPFP:K8515
Removal and InstallationEHS000WN
The passenger air bag module originally installed in the vehicle uses direct-connect style harness connectors.
Service replacement passenger air bag modules use tab-locking style harness connectors. If the passenger
air bag module is replaced or if the direct-connect harness connectors are damaged, the vehicle wiring har-
ness must be modified to allow connection of the service replacement passenger air bag module. Refer to
SRS-51, "
WIRING HARNESS MODIFICATION" for wiring harness modification procedure.
REMOVAL
CAUTION:

Do not attempt to repair or replace damaged direct-connect front passenger air bag module con-
nectors. If a direct-connect harness connector is damaged, the front passenger air bag must be
replaced and the wiring harness modified.

Before servicing SRS, turn the ignition switch off, disconnect both battery cables and wait at least
3 minutes.

Always work from the side of or under front passenger air bag module.
1. Remove the glove box. Refer to IP-10, "
INSTRUMENT PANEL ASSEMBLY" .
2. Remove 2 nuts (through glove box opening) retaining front pas-
senger air bag module to instrument panel crossmember.
3. Disconnect the air bag module electrical connectors.

For removal/installation of the direct-connect SRS connec-
tors, refer to SRS-7, "
Direct-connect SRS Component Con-
nectors" .
4. Remove the instrument panel assembly from the vehicle. Refer
to IP-10, "
INSTRUMENT PANEL ASSEMBLY" .
5. Remove front passenger air bag module nuts and remove air
bag module from the instrument panel assembly.
CAUTION:

When servicing the SRS, do not work from directly in front
of air bag module.

Always place front passenger air bag module with caution
label 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 nuts after removal; replace with new nuts.

Do not expose the front passenger air bag module to tem-
peratures exceeding 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.

For removal/installation of the direct-connect SRS connec-
tors, refer to SRS-7, "
Direct-connect SRS Component Con-
nectors" .
INSTALLATION
Original Passenger Air Bag Module
To install, reverse the removal procedure.
WHIA0110E
W H I A 0111 E
SBF 8 14 E

FRONT PASSENGER AIR BAG MODULE
SRS-51
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SRS
Revision: August 20072004 QX56

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

Always work from the side of or under front passenger air bag module.

After the work is completed, perform self-diagnosis to check that no malfunction is detected.
Refer to SRS-20, "
SRS Operation Check" .
Service Replacement Passenger Air Bag Module
1. Install the front passenger air bag module to the instrument
panel pad assembly.
2. Install the instrument panel assembly. Refer to IP-10, "
INSTRUMENT PANEL ASSEMBLY" .
3. Connect the front passenger air bag module harness connector to yellow 4-pin service replacement air
bag connector and fasten connector to mounting bracket.
CAUTION:

Always work from the side of or under front passenger air bag module.

After the work is completed, perform self-diagnosis to check that no malfunction is detected.
Refer to SRS-20, "
SRS Operation Check" .
WIRING HARNESS MODIFICATION
The passenger air bag module originally installed in the vehicle uses direct-connect style harness connectors.
Service replacement passenger air bag modules use tab-locking style harness connectors. If the passenger
air bag module is replaced or if the direct-connect harness connectors are damaged, the vehicle wiring har-
ness must be modified to allow connection of the service replacement passenger air bag module.
NOTE:
The wiring harness modification is to be performed only if the vehicle is equipped with the original passenger
air bag which uses direct-connect harness connectors. If the passenger air bag is to be replaced in a vehicle
that has already had the service replacement passenger air bag installed, the wiring harness modification is
not required.
CAUTION:

Do not attempt to repair or replace damaged direct-connect front passenger air bag module con-
nectors. If a direct-connect harness connector is damaged, the front passenger air bag must be
replaced and the wiring harness modified.

Before servicing SRS, turn the ignition switch off, disconnect both battery cables and wait at least
3 minutes.

Always work from the side of or under front passenger air bag module.

After the work is completed, perform self-diagnosis to check that no malfunction is detected.
Refer to SRS-20, "
SRS Operation Check" .
1. Locate the yellow and orange direct-connect passenger air bag module harness connectors.
2. Use wire cutters to cut back both previously used direct-connect passenger air bag module harness con-
nectors from the vehicle wiring harness approximately 50 mm (1.9 in) from the connectors.
3. Remove approximately 150 mm (5.9 in) of the vehicle harness covering from the cut end.
WHIA0110E

SRS-52
FRONT PASSENGER AIR BAG MODULE
Revision: August 20072004 QX56
4. Slide a piece of dual-wall heat shrink tubing (provided in the pas-
senger air bag service kit) onto each wire of the previously used
vehicle wiring harness.
5. Fold each wire back and insert into the end of the heat shrink
tubing so that the end of the wire is approximately centered in
the heat shrink tubing.
6. Use a heat gun to shrink the heat shrink tubing and seal the wire.
7. Use electrical tape to secure the modified circuits to the outside of the wiring harness.
8. Locate the front passenger air bag service replacement connec-
tor that is taped back to the main harness. Unwrap the tape to
access the yellow service replacement connector and remove
the dust cover from the connector.
LHIA0017E
WHIA0062E
WHIA0118E

TF-1
TRANSFER
D DRIVELINE/AXLE
CONTENTS
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SECTION TF
A
B
TF
Revision: August 20072004 QX56 PREPARATION ........................................................... 4
Special Service Tools ............................................... 4
Commercial Service Tools ........................................ 7
PRECAUTIONS .......................................................... 8
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 8
Precautions .............................................................. 8
Service Notice .......................................................... 9
Wiring Diagrams and Trouble Diagnosis .................. 9
ALL-MODE 4WD SYSTEM ...................................... 10
Cross-sectional View .............................................. 10
Control System ........................................................11
ALL-MODE 4WD TRANSFER BASIC CONTROL
... 12
HYDRAULIC CONTROL CIRCUITS ................... 12
OUTLINE ............................................................. 12
CONTROL SYSTEM DIAGRAM ......................... 13
INDICATIONS OF 4WD WARNING LAMP ......... 13
CAN Communication .............................................. 13
SYSTEM DESCRIPTION .................................... 13
Location of Electrical Parts ..................................... 14
Description of Electrical Parts ................................ 15
TRANSFER MOTOR .......................................... 15
WAIT DETECTION SWITCH .............................. 15
2-4WD SHIFT SOLENOID VALVE ...................... 15
LINE PRESSURE SWITCH ................................ 16
Circuit Diagram for Quick Pinpoint Check .............. 17
Wiring Diagram — T/F — ....................................... 18
ON BOARD DIAGNOSTIC SYSTEM DESCRIP-
TION .......................................................................... 27
Trouble Diagnosis without CONSULT-II ................. 27
DESCRIPTION .................................................... 27
SELF-DIAGNOSTIC PROCEDURE .................... 28
INDICATIONS OF 4WD WARNING LAMP ......... 28CONSULT-II Function (ALL MODE AWD/4WD) ..... 31
Trouble Diagnosis with CONSULT-II ...................... 31
SELF-DIAGNOSIS .............................................. 31
SELF-DIAGNOSTIC ITEMS ................................ 32
DATA MONITOR ................................................. 34
DATA MONITOR ITEMS ..................................... 35
REFERENCE VALUE IN DATA MONITOR MODE
... 38
WORK SUPPORT ............................................... 41
CLUTCH FORCE RELEASE LIMIT ADJUST-
MENT .................................................................. 42
TROUBLE DIAGNOSIS — INTRODUCTION ........... 44
Introduction ............................................................. 44
DESCRIPTION .................................................... 44
DIAGNOSTIC WORKSHEET .............................. 44
Work Flow ............................................................... 46
HOW TO PERFORM TROUBLE DIAGNOSES
FOR QUICK AND ACCURATE REPAIR ............. 46
TROUBLE DIAGNOSIS — BASIC INSPECTION .... 47
Listen to Customer Complaints .............................. 47
Transfer Fluid Check .............................................. 47
Road Test ............................................................... 47
PREPARATION FOR ROAD TEST ..................... 47
1. CHECK BEFORE ENGINE IS STARTED ....... 48
2. CHECK AT IDLE .............................................. 49
3. CRUISE TEST ................................................. 53
TROUBLE DIAGNOSIS — GENERAL DESCRIP-
TION .......................................................................... 55
Transfer Control Unit Terminals and Reference
Value ....................................................................... 55
TRANSFER CONTROL UNIT HARNESS CON-
NECTOR LAYOUT .............................................. 55
TRANSFER CONTROL UNIT INSPECTION
TABLE ................................................................. 55
DTC U1000, U1001 CAN COMMUNICATION LINE ... 59
CAN Communication System Inspection ................ 59
4WD SOLENOID VALVE .......................................... 60
Diagnostic Procedure ............................................. 60
2-4WD SHIFT SOLENOID VALVE AND 4WD SHIFT

TF-3
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TF
Revision: August 20072004 QX56 FRONT CASE ......................................................... 131
Inspection ............................................................. 131
PLANETARY CARRIER .................................... 131
SUN GEAR ....................................................... 131
INTERNAL GEAR ............................................. 131
SHIFT ROD COMPONENTS ............................ 131
CENTER CASE ...................................................... 133
Inspection ............................................................. 133
BEARINGS ........................................................ 133
SUB-OIL PUMP ................................................ 133
MAIN OIL PUMP ............................................... 133
MAINSHAFT ..................................................... 133
CONTROL VALVE ............................................ 134
CLUTCH ............................................................ 134
FRONT CASE ......................................................... 136
Assembly .............................................................. 136
PLANETARY CARRIER, SUN GEAR AND
INTERNAL GEAR ............................................. 136
SHIFT ROD ASSEMBLY ................................... 139CENTER CASE .......................................................140
Assembly ..............................................................140
OIL FILTER ........................................................140
SUB OIL PUMP .................................................140
MAIN OIL PUMP ...............................................141
CONTROL VALVE .............................................142
CLUTCH PISTON ..............................................144
MAINSHAFT AND CLUTCH DRUM ..................145
FRONT DRIVE SHAFT AND DRIVE CHAIN .....148
ASSEMBLY .............................................................149
Final Assembly .....................................................149
SERVICE DATA AND SPECIFICATIONS (SDS) ....153
General Specifications ..........................................153
Inspection and Adjustment ...................................153
CLEARANCE BETWEEN INNER GEAR AND
OUTER GEAR ...................................................153
CLUTCH ............................................................153
PINION GEAR END PLAY ................................153
CLEARANCE BETWEEN SHIFT FORK AND
SLEEVE ............................................................153
SELECTIVE PARTS ..........................................153

TF-4
PREPARATION
Revision: August 20072004 QX56
PREPARATIONPFP:00002
Special Service ToolsEDS0017H
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
ST30021000
(—)
PullerRemoving carrier bearing
a: 110 mm (4.33 in) dia.
b: 68 mm (2.68 in) dia.
ST30031000
(—)
PullerRemoving front drive shaft bearing
a: 90 mm (3.54 in) dia.
b: 50 mm (1.97 in) dia.
ST30720000
(J-25405)
DriftInstalling mainshaft front bearing and oil seal
a: 77 mm (3.03 in) dia.
b: 55.5 mm (2.185 in) dia.
ST33220000
(—)
DriftInstallation needle bearings
a: 37 mm (1.46 in) dia.
b: 31 mm (1.22 in) dia.
c: 22 mm (0.87 in) dia.
KV40100621
(J-25273)
DriftInstalling front drive shaft front and rear bear-
ing
a: 76 mm (2.99 in) dia.
b: 69 mm (2.72 in) dia.
ST30032000
(J-26010-01)
BaseInstalling front drive shaft bearing
a: 38 mm (1.50 in) dia.
b: 80 mm (3.15 in) dia.
ST33052000
(—)
AdapterRemoving front drive shaft bearing
a: 28 mm (1.10 in) dia.
b: 22 mm (0.87 in) dia.
NT411
NT411
NT658
ZZA1046D
NT086
NT660
NT431