2001 INFINITI QX4 wiring diagram

MRS327A
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
Wiring Diagram Ð SRS Ð (Cont'd)
RS-37

STARTING & CHARGING SYSTEM
SECTION
SC
CONTENTS
PRECAUTIONS...............................................................2
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER²...............2
Wiring Diagrams and Trouble Diagnosis .....................2
PREPARATION...............................................................3
Special Service Tool ....................................................3
BATTERY.........................................................................4
How to Handle Battery ................................................4
METHODS OF PREVENTING OVER-DISCHARGE......4
CHECKING ELECTROLYTE LEVEL............................4
SPECIFIC GRAVITY CHECK......................................5
CHARGING THE BATTERY........................................6
Trouble Diagnoses with Battery/Starting/Charging
System Tester ..............................................................7
DIAGNOSTIC RESULT ITEM CHART..........................9
STARTING SYSTEM.....................................................10
System Description ....................................................10
Wiring Diagram - START -......................................... 11
Trouble Diagnoses with Battery/Starting/Charging
System Tester ............................................................12
DIAGNOSTIC RESULT ITEM CHART........................13
WORK FLOW..........................................................14
DIAGNOSTIC PROCEDURE 1..................................15
DIAGNOSTIC PROCEDURE 2..................................17
MINIMUM SPECIFICATION OF CRANKING
VOLTAGE REFERENCING COOLANT
TEMPERATURE
......................................................17
Construction ...............................................................18
Removal and Installation ...........................................18
Pinion/Clutch Check ..................................................18
CHARGING SYSTEM....................................................19
System Description ....................................................19
Wiring Diagram - CHARGE -.....................................20
Trouble Diagnoses with Battery/Starting/Charging
System Tester ............................................................21
DIAGNOSTIC RESULT ITEM CHART........................23
WORK FLOW..........................................................24
DIAGNOSTIC PROCEDURE 1..................................25
DIAGNOSTIC PROCEDURE 2..................................26
DIAGNOSTIC PROCEDURE 3..................................27
MALFUNCTION INDICATOR....................................27
Construction ...............................................................28
Removal and Installation ...........................................28
SERVICE DATA AND SPECIFICATIONS (SDS).........29
Battery........................................................................29
Starter ........................................................................29
Alternator ...................................................................29
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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

Wiring Diagram Ð START ÐNBSC0005
MEL652L
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STARTING SYSTEM
Wiring Diagram Ð START Ð
SC-11

Wiring Diagram Ð CHARGE ÐNBSC0010
MEL653L
CHARGING SYSTEM
Wiring Diagram Ð CHARGE Ð
SC-20

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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MEF040DB
IBefore replacing Transfer control unit, perform Transfer
control unit input/output signal inspection and make sure
whether Transfer control unit functions properly or not.
(See page TF-55.)
Service NoticeNBTF00021) Before proceeding with disassembly, thoroughly clean the outside of the all-mode 4WD transfer. It is
important to prevent the internal parts from becoming contaminated by dirt or other foreign matter.
2) Disassembly should be done in a clean work area.
3) Use lint-free cloth or towels for wiping parts clean. Common shop rags can leave fibers that could inter-
fere with the operation of the all-mode 4WD transfer.
4) Place disassembled parts in order for easier and proper assembly.
5) All parts should be carefully cleaned with a general purpose, non-flammable solvent before inspection or
reassembly.
6) Gaskets, seals and O-rings should be replaced any time the all-mode 4WD transfer is disassembled.
7) It is very important to perform functional tests whenever they are indicated.
8) The valve body contains precision parts and requires extreme care when parts are removed and serviced.
Place removed parts in a parts rack in order to replace them in correct positions and sequences. Care will
also prevent springs and small parts from becoming scattered or lost.
9) Properly installed valves, sleeves, plugs, etc. will slide along bores in valve body under their own weight.
10) Before assembly, apply a coat of recommended ATF to all parts. Apply petroleum jelly to protect O-rings
and seals, and to hold bearings and washers in place during assembly. Do not use grease.
11) Extreme care should be taken to avoid damage to O-rings, seals and gaskets when assembling.
12) After overhaul, refill the transfer with new ATF.
13) When the all-mode 4WD transfer drain plug is removed, only some of the fluid is drained. Old all-mode
4WD transfer fluid will remain in torque converter and ATF cooling system. Always follow the procedures,
MA-22, ªChanging All-mode 4WD Transfer Fluidº.
Wiring Diagrams and Trouble DiagnosisNBTF0003When you read wiring diagrams, refer to the following:
IGI-11, ªHOW TO READ WIRING DIAGRAMSº
IEL-9, ªPOWER SUPPLY ROUTINGº
When you perform trouble diagnosis, refer to the following:
IGI-35, ªHOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSISº
IGI-24, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº
PRECAUTIONS
Precautions (Cont'd)
TF-4

Wiring Diagram Ð TF ÐNBTF0010
MTF061A
ALL-MODE 4WD SYSTEM
Wiring Diagram Ð TF Ð
TF-18