2001 INFINITI QX4 02 sensor

FOR SIDE COLLISION=NBRS0049S02To repair the SRS for a side collision, perform the following steps.
When the side air bag is activated in the side collision:
1) Replace the following component:
þ All parts of front seatback (including front seatback frame) with side air bag module (on the side on which
side air bag is activated)
þ Diagnosis sensor unit
þ Satellite sensor (on the side on which side air bag is activated)
2) Check the SRS components and the related parts using the table shown below.
IReplace any SRS components and the related parts showing visible signs of damage (dents, cracks,
deformation).
3) Conduct self-diagnosis using CONSULT-II or ªAIR BAGº warning lamp. Refer to ªSRS Operation Checkº
for details (RS-38). Ensure entire SRS operation properly.
When SRS is not activated in the side collision:
1) Check the SRS components and the related parts using the table shown below.
IReplace any SRS components and the related parts showing visible signs of damage (dents, cracks,
deformation).
2) Conduct self-diagnosis using CONSULT-II or ªAIR BAGº warning lamp. Refer to ªSRS Operation Checkº
for details (RS-38). Ensure entire SRS operation properly.
SRS Inspection (For side collision)NBRS0049S0201
PartSide air bag is acti-
vatedSRS is NOT activated
Built-in side air bags
module (LH or RH)REPLACE all parts of
front seatback with
deployed side air bag
module.1. Check for visible signs of damage (dents, tears, deformation) of the seatback
on the collision side.
2. If damagedÐREPLACE the damaged seat parts with new bolts and remove
the side air bag module.
3. Check for visible signs of damaged (tesrs etc.) of the side air bag module.
4. Check harness and connectors for damage, and terminals for deformities.
5. If no damaged is found, reinstall the side air bag module with new torx nuts
coated with bonding agent.
6. If damagedÐREPLACE the side air bag module with new torx nuts coated with
bonding agent. Air bag must be deployed before disposing of it.
Satellite sensor (LH
or RH)REPLACE the satel-
lite sensor on the col-
lision side with new
nuts coated with
bonding agent.
(Repair the center
pillar inner, etc. before
installing new one if
damaged.)1. Remove the satellite sensor on the collision side. Check harness connectors
for damage, terminals for deformities, and harness for binding.
2. Check for visible signs of damage (dents, cracks, deformation) of the satellite
sensor.
3. Install the satellite sensor to check fit.
4. If no damage is found, reinstall the satellite sensor with new nuts coated with
bonding agent.
5. If damagedÐREPLACE the satellite sensor with new nuts coated with bonding
agent.
Diagnosis sensor unit REPLACE the diag-
nosis sensor unit with
the new bolts.1. Check case and bracket for dents, cracks or deformities.
2. Check connectors for damage, and terminals for deformities.
3. If no damage is found, reinstall the diagnosis sensor unit with new special bolts
and ground bolt.
4. If damagedÐREPLACE. Install the diagnosis sensor unit with new special
bolts and ground bolt.
Seat belt pre-ten-
sioner assembly1. Check if the seat belt can be extended smoothly.
If the seat belt cannot be extended smoothly.
± Check for deformities of the center pillar inner.
± If the center pillar inner has no damage, REPLACE the seat belt pre-tensioner assembly.
2. Remove the seat belt pre-tensioner assembly on the collision side. Check harness cover and connec-
tors for damage, terminals for deformities, and harness for binding.
3. Check for visible signs of damage (dents, cracks, deformation) of the seat belt pre-tensioner assembly.
4. If no damage is found, reinstall the seat belt pre-tensioner assembly.
5. If damagedÐREPLACE the seat belt pre-tensioner assembly with new bolts coated with bonding
agent. The seat belt pre-tensioner assembly must be deployed before disposing of it.
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
Collision Diagnosis (Cont'd)
RS-61

Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBSC0001The Supplemental Restraint System such as ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº used along with
a seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of
collision. The SRS system composition which is available to INFINITI QX4 is as follows:
IFor a frontal collision
The Supplemental Restraint System consists of driver air bag module (located in the center of the steer-
ing wheel), front passenger air bag module (located on the instrument panel on passenger side), seat belt
pre-tensioners, a diagnosis sensor unit, warning lamp, wiring harness and spiral cable.
IFor a side collision
The Supplemental Restraint System consists of side air bag module (located in the outer side of front seat),
satellite sensor, diagnosis sensor unit (one of components of air bags for a frontal collision), wiring harness,
warning lamp (one of components of air bags for a frontal collision).
Information necessary to service the system safely is included in theRS sectionof this Service Manual.
WARNING:
ITo avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be performed
by an authorized INFINITI dealer.
IImproper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the RS section.
IDo not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. Spiral cable and wiring harnesses covered with yellow insulation tape either just
before the harness connectors or for the complete harness are related to the SRS.
Wiring Diagrams and Trouble DiagnosisNBSC0002When you read wiring diagrams, refer to the following:
IGI-11, ªHOW TO READ WIRING DIAGRAMSº
IEL-9, ªPOWER SUPPLY ROUTINGº for power distribution circuit
When you perform trouble diagnosis, refer to the following:
IGI-35, ªHOW TO FOLLOW TEST GROUP IN TROUBLE DIAGNOSISº
IGI-24, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº
PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
SC-2

Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBST0044The Supplemental Restraint System such as ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº used along with
a seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of
collision. The SRS system composition which is available to INFINITI QX4 is as follows:
IFor a frontal collision
The Supplemental Restraint System consists of driver air bag module (located in the center of the steer-
ing wheel), front passenger air bag module (located on the instrument panel on passenger side), seat belt
pre-tensioners, a diagnosis sensor unit, warning lamp, wiring harness and spiral cable.
IFor a side collision
The Supplemental Restraint System consists of side air bag module (located in the outer side of front seat),
satellite sensor, diagnosis sensor unit (one of components of air bags for a frontal collision), wiring harness,
warning lamp (one of components of air bags for a frontal collision).
Information necessary to service the system safely is included in theRS sectionof this Service Manual.
WARNING:
ITo avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be performed
by an authorized INFINITI dealer.
IImproper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the RS section.
IDo not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. Spiral cable and wiring harnesses covered with yellow insulation tape either just
before the harness connectors or for the complete harness are related to the SRS.
Precautions for Steering SystemNBST0002IBefore disassembly, thoroughly clean the outside of the unit.
IDisassembly should be done in a clean work area. It is important to prevent the internal parts from
becoming contaminated by dirt or other foreign matter.
IPlace disassembled parts in order, on a parts rack, for easier and proper assembly.
IUse nylon cloths or paper towels to clean the parts; common shop rags can leave lint that might
interfere with their operation.
IBefore inspection or reassembly, carefully clean all parts with a general purpose, non-flammable
solvent.
IBefore assembly, apply a coat of recommended power steering fluid* to hydraulic parts. Vaseline
may be applied to O-rings and seals. Do not use any grease.
IReplace all gaskets, seals and O-rings. Avoid damaging O-rings, seals and gaskets during instal-
lation. Perform functional tests whenever designated.
*: Genuine Nissan PSF II or equivalent. Refer to MA-11, ªFluids and Lubricantsº.
PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
ST-2

SBR686C
Removal and InstallationNBSU00261. Support axle and suspension components with a suitable jack
and block.
2. Disconnect brake hydraulic line and parking brake cables at
back plates.
CAUTION:
IUse flare nut wrench when removing and installing brake
tubes.
IBefore removing the rear suspension assembly, discon-
nect the ABS wheel sensor from the assembly. Then move
it away from the rear suspension assembly. Failure to do
so may result in damage to the sensor wires and the sen-
sor becoming inoperative.
3. Remove stabilizer bar from body.
4. Remove upper links and lower links from body.
5. Remove panhard rod from body.
6. Disconnect rear end of propeller shaft. Refer to PD-6,
ªRemoval and Installationº.
7. Remove upper end nuts of shock absorber.
SRA935
Final tightening for rubber parts requires to be carried out
under unladen condition with tires on ground.
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REAR SUSPENSION
Removal and Installation
SU-17

TRANSFER
SECTION
TF
CONTENTS
PRECAUTIONS...............................................................3
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER²...............3
Precautions ..................................................................3
Service Notice..............................................................4
Wiring Diagrams and Trouble Diagnosis .....................4
PREPARATION...............................................................5
Special Service Tools ..................................................5
Commercial Service Tools ...........................................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
Location of Electrical Parts ........................................14
Description of Electrical Parts ...................................15
TRANSFER MOTOR................................................15
WAIT DETECTION SWITCH.....................................15
2-4WD SHIFT SOLENOID VALVE.............................16
LINE PRESSURE SWITCH.......................................16
Circuit Diagram for Quick Pinpoint Check.................17
Wiring Diagram - TF -................................................18
ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION...............................................................27
Trouble Diagnosis without CONSULT-II ....................27
DESCRIPTION........................................................27
SELF-DIAGNOSTIC PROCEDURE............................28
INDICATIONS OF 4WD WARNING LAMP..................29
Trouble Diagnosis with CONSULT-II .........................30
SELF-DIAGNOSIS...................................................30
SELF-DIAGNOSTIC ITEMS......................................31
DATA MONITOR......................................................33
DATA MONITOR ITEMS...........................................34
REFERENCE VALUE IN DATA MONITOR MODE......36
WORK SUPPORT....................................................38
CLUTCH FORCE RELEASE LIMIT ADJUSTMENT.....39
TROUBLE DIAGNOSIS - INTRODUCTION..................41Introduction ................................................................41
DESCRIPTION........................................................41
DIAGNOSTIC WORKSHEET.....................................41
Work Flow ..................................................................43
HOW TO PERFORM TROUBLE DIAGNOSES FOR
QUICK AND ACCURATE REPAIR
.............................43
TROUBLE DIAGNOSIS - BASIC INSPECTION...........44
Listen to Customer Complaints .................................44
Transfer Fluid Check .................................................44
Road Test...................................................................44
PREPARATION FOR ROAD TEST............................44
1. CHECK BEFORE ENGINE IS STARTED...............45
2. CHECK AT IDLE..................................................47
3. CRUISE TEST.....................................................51
TROUBLE DIAGNOSIS - GENERAL
DESCRIPTION...............................................................54
Transfer Control Unit Terminals and Reference
Value ..........................................................................54
REMOVAL AND INSTALLATION OF TRANSFER
CONTROL UNIT
......................................................54
INSPECTION OF TRANSFER CONTROL UNIT..........54
TRANSFER CONTROL UNIT INSPECTION TABLE....55
VEHICLE SPEED SENSOR (FRONT
REVOLUTION SENSOR)..............................................61
Diagnostic Procedure ................................................61
4WD SOLENOID VALVE...............................................64
Diagnostic Procedure ................................................64
2-4WD SHIFT SOLENOID VALVE AND 4WD
SHIFT SWITCH..............................................................66
Diagnostic Procedure ................................................66
TRANSFER MOTOR AND TRANSFER MOTOR
RELAY...........................................................................70
Diagnostic Procedure ................................................70
TRANSFER FLUID TEMPERATURE SENSOR............73
Diagnostic Procedure ................................................73
ATP SWITCH, WAIT DETECTION SWITCH AND
NEUTRAL-4LO SWITCH...............................................76
Diagnostic Procedure ................................................76
CLUTCH PRESSURE SWITCH....................................80
Diagnostic Procedure ................................................80
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LINE PRESSURE SWITCH...........................................83
Diagnostic Procedure ................................................83
ABS OPERATION SIGNAL...........................................86
Diagnostic Procedure ................................................86
DATA ERASE/DISPLAY...............................................88
Diagnostic Procedure ................................................88
SHIFT ACTUATOR........................................................89
Diagnostic Procedure ................................................89
SHIFT ACTUATOR POSITION SWITCH......................92
Diagnostic Procedure ................................................92
SHIFT ACTUATOR CIRCUIT........................................94
Diagnostic Procedure ................................................94
TROUBLE DIAGNOSES FOR SYMPTOMS.................98
Symptom 1. 4WD Shift Indicator Lamp Does Not
Turn ON .....................................................................98
Symptom 2. 4WD Warning Lamp Does Not Turn
ON............................................................................100
Symptom 3. 4WD Shift Indicator Lamp Does Not
Turn OFF .................................................................102
Symptom 4. ATP Warning Lamp Does Not Turn
ON............................................................................102
Symptom 5. 4LO Indicator Lamp Does Not Turn
ON............................................................................104
Symptom 6. 4WD Shift Indicator Lamp Does Not
Indicate²4H²............................................................106
Symptom 7. 4WD Shift Indicator Lamp Repeats
Flickering..................................................................107
Symptom 8. Tight Corner Braking Symptom...........108
Symptom 9. 4WD System Does Not Operate.........109
COMPONENT INSPECTION....................................... 111
4WD Shift Switch ..................................................... 111
2-4WD Shift Solenoid Valve and Transfer Fluid
Temperature Sensor ................................................ 111
4WD Solenoid Valve, Clutch Pressure Switch
and Line Pressure Switch........................................ 111
Front Revolution Sensor .......................................... 112
Transfer Dropping Resistor...................................... 112
ATP Switch, Neutral-4LO Switch and Wait
Detection Switch ...................................................... 112
Transfer Motor ......................................................... 113
Transfer Motor Relay ............................................... 113
Transfer Sub-harness .............................................. 113
FRONT REVOLUTION SENSOR SUB-HARNESS
CONNECTOR
........................................................ 113
TRANSFER SWITCH ASSEMBLY SUB-HARNESS
CONNECTOR
........................................................ 114
TRANSFER TERMINAL CORD ASSEMBLY SUB-
HARNESS CONNECTOR
....................................... 114
Transfer Shift Relay (High & low) ............................ 114
Actuator & Actuator Position Switch ........................ 115
ACTUATOR........................................................... 115
ACTUATOR POSITION SWITCH............................ 115
ON-VEHICLE SERVICE.............................................. 116
Replacing Oil Seal ................................................... 116
FRONT CASE OIL SEAL........................................ 116
SHIFT SHAFT OIL SEAL........................................ 117
REAR OIL SEAL.................................................... 117
Transfer Motor ......................................................... 117
REMOVAL............................................................. 117
INSTALLATION...................................................... 117
Transfer Oil Filter ..................................................... 118
REMOVAL............................................................. 118
INSTALLATION...................................................... 118
REMOVAL AND INSTALLATION............................... 119
Removal ................................................................... 119
Installation ................................................................ 119
OVERHAUL.................................................................120
Transfer Gear Control ..............................................120
Transfer Components ..............................................121
DISASSEMBLY............................................................123
Rear Case................................................................123
DISASSEMBLY......................................................123
Center Case.............................................................123
DISASSEMBLY......................................................123
Front Case ...............................................................133
DISASSEMBLY......................................................133
REPAIR FOR COMPONENT PARTS.........................137
Front Case ...............................................................137
INSPECTION.........................................................137
Center Case.............................................................138
INSPECTION.........................................................138
ASSEMBLY..................................................................141
Front Case ...............................................................141
ASSEMBLY...........................................................141
Center Case.............................................................145
ASSEMBLY...........................................................145
Final Assembly.........................................................153
SERVICE DATA AND SPECIFICATIONS (SDS).......157
General Specifications .............................................157
Inner Gear and Outer Gear .....................................157
SUB-OIL PUMP.....................................................157
MAIN OIL PUMP....................................................157
Control Valve ...........................................................157
VALVE..................................................................157
SPRING................................................................157
Clutch .......................................................................158
DRIVE PLATE.......................................................158
DRIVEN PLATE.....................................................158
RETURN SPRING..................................................158
RETAINING PLATE................................................158
Seal Ring (Mainshaft side) ......................................159
Bearing Race (Thrust needle bearing side) ............159
Snap Ring (Sun gear side) ......................................159
CONTENTS(Cont'd)
TF-2

Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBTF0001The Supplemental Restraint System such as ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº used along with
a seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of
collision. The SRS system composition which is available to INFINITI QX4 is as follows:
IFor a frontal collision
The Supplemental Restraint System consists of driver air bag module (located in the center of the steer-
ing wheel), front passenger air bag module (located on the instrument panel on passenger side), seat belt
pre-tensioners, a diagnosis sensor unit, warning lamp, wiring harness and spiral cable.
IFor a side collision
The Supplemental Restraint System consists of side air bag module (located in the outer side of front seat),
satellite sensor, diagnosis sensor unit (one of components of air bags for a frontal collision), wiring harness,
warning lamp (one of components of air bags for a frontal collision).
Information necessary to service the system safely is included in theRSsection of this Service Manual.
WARNING:
ITo avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be performed
by an authorized INFINITI dealer.
IImproper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the RS section.
IDo not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. Spiral cable and wiring harnesses covered with yellow insulation tape either just
before the harness connectors or for the complete harness are related to the SRS.
SEF289H
PrecautionsNBTF0092IBefore connecting or disconnecting the Transfer control
unit harness connector, turn ignition switch OFF and dis-
connect negative battery terminal. Failure to do so may
damage the Transfer control unit. Because battery voltage
is applied to Transfer control unit even if ignition switch
is turned off.
SEF291H
IWhen connecting or disconnecting pin connectors into or
from Transfer control unit, take care not to damage pin
terminals (bend or break).
Make sure that there are not any bends or breaks on
Transfer control unit pin terminal, when connecting pin
connectors.
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PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
TF-3

ALL-MODE 4WD TRANSFER BASIC CONTROLNBTF0007S01
SMT043D
HYDRAULIC CONTROL CIRCUITSNBTF0007S02
SMT040D
OUTLINENBTF0007S03All-mode 4WD transfer is controlled by the transfer control unit and
sensors.
If a malfunction occurs in the all-mode 4WD system, the 4WD
warning lamp lights up to indicate the system malfunction. There
are two ways to identify the cause of the malfunction.
1) Performing the self-diagnosis. (The 4WD warning lamp will
indicate what kind of malfunction has occurred by flickering.)
2) Performing diagnosis using CONSULT-II.
ALL-MODE 4WD SYSTEM
Control System (Cont'd)
TF-12