2001 INFINITI QX4 Electrical Wiring

CONSULT-II Reference Value in Data Monitor
Mode ........................................................................585
ECM Terminals and Reference Value .....................585
On Board Diagnosis Logic.......................................586
Possible Cause ........................................................586
DTC Confirmation Procedure ..................................586
Wiring Diagram ........................................................587
Diagnostic Procedure ..............................................588
DTC P1491 VACUUM CUT VALVE BYPASS
VALVE..........................................................................591
Description ...............................................................591
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................591
ECM Terminals and Reference Value .....................591
On Board Diagnosis Logic.......................................592
Possible Cause ........................................................592
DTC Confirmation Procedure ..................................592
Overall Function Check ...........................................593
Wiring Diagram ........................................................594
Diagnostic Procedure ..............................................595
DTC P1605 A/T DIAGNOSIS COMMUNICATION
LINE.............................................................................603
Component Description ...........................................603
On Board Diagnosis Logic.......................................603
Possible Cause ........................................................603
DTC Confirmation Procedure ..................................603
DTC P1706 PARK/NEUTRAL POSITION (PNP)
SWITCH.......................................................................604
Component Description ...........................................604
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................604
ECM Terminals and Reference Value .....................604
On Board Diagnosis Logic.......................................604
Possible Cause ........................................................604
DTC Confirmation Procedure ..................................605
Overall Function Check ...........................................606
Wiring Diagram ........................................................607
Diagnostic Procedure ..............................................608
VARIABLE INDUCTION AIR CONTROL SYSTEM
(VIAS)...........................................................................610
Description ...............................................................610
ECM Terminals and Reference Value ..................... 611
Wiring Diagram ........................................................612
Diagnostic Procedure ..............................................613
INJECTOR...................................................................616
Component Description ...........................................616
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................616
ECM Terminals and Reference Value .....................616
Wiring Diagram ........................................................617Diagnostic Procedure ..............................................618
START SIGNAL...........................................................621
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................621
ECM Terminals and Reference Value .....................621
Wiring Diagram ........................................................622
Diagnostic Procedure ..............................................623
FUEL PUMP.................................................................625
System Description ..................................................625
Component Description ...........................................625
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................625
ECM Terminals and Reference Value .....................626
Wiring Diagram ........................................................627
Diagnostic Procedure ..............................................628
POWER STEERING OIL PRESSURE SWITCH.........634
Component Description ...........................................634
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................634
ECM Terminals and Reference Value .....................634
Wiring Diagram ........................................................635
Diagnostic Procedure ..............................................636
REFRIGERANT PRESSURE SENSOR......................639
Description ...............................................................639
ECM Terminals and Reference Value .....................639
Wiring Diagram ........................................................640
Diagnostic Procedure ..............................................641
ELECTRICAL LOAD SIGNAL.....................................643
ECM Terminals and Reference Value .....................643
Wiring Diagram ........................................................644
Diagnostic Procedure ..............................................645
MIL & DATA LINK CONNECTORS............................648
Wiring Diagram ........................................................648
SERVICE DATA AND SPECIFICATIONS (SDS).......649
Fuel Pressure Regulator..........................................649
Idle Speed and Ignition Timing ................................649
Mass Air Flow Sensor..............................................649
Engine Coolant Temperature Sensor ......................649
Heated Oxygen Sensor 1 Heater (Front) ................649
Fuel Pump ...............................................................649
IACV-AAC Valve ......................................................649
Injector .....................................................................649
Resistor ....................................................................649
Throttle Position Sensor ..........................................650
Calculated Load Value.............................................650
Intake Air Temperature Sensor ................................650
Heated Oxygen Sensor 2 Heater (Rear).................650
Crankshaft Position Sensor (REF) ..........................650
Fuel Tank Temperature Sensor ...............................650
Camshaft Position Sensor (PHASE) .......................650GI
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CONTENTS(Cont'd)
EC-7

Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBEC0002The 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 front 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 On Board Diagnostic (OBD)
System of Engine and A/T
NBEC0003The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
IBe sure to turn the ignition switch OFF and disconnect the negative battery terminal before any
repair or inspection work. The open/short circuit of related switches, sensors, solenoid valves, etc.
will cause the MIL to light up.
IBe sure to connect and lock the connectors securely after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
ICertain systems and components, especially those related to OBD, may use a new style slide-
locking type harness connector. For description and how to disconnect, refer to EL-6, ªHARNESS
CONNECTOR (SLIDE-LOCKING TYPE)º.
IBe sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to light up due to the short circuit.
IBe sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfunction of the fuel injection system, etc.
IBe sure to erase the unnecessary malfunction information (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
EC-14

SEF348N
IWhen measuring ECM signals with a circuit tester, never
allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
IDo not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the
ECM's transistor. Use a ground other than the ECM
terminals, such as the ground.
SEF099WB
IRegarding model R50, ª-B1º indicates the right bank and
ª-B2º indicates the left bank as shown in the figure.
IBank 1 includes No. 1 cylinder.
Wiring Diagrams and Trouble DiagnosisNBEC0006When you read Wiring diagrams, refer to the following:
IGI-34, ªHOW TO READ WIRING DIAGRAMSº
IEL-9, ªPOWER SUPPLY ROUTINGº for power distribution circuit
When you perform trouble diagnosis, refer to the following:
IGI-38, ªHOW TO FOLLOW TEST GROUP IN TROUBLE DIAGNOSISº
IGI-34, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº
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PRECAUTIONS
Precautions (Cont'd)
EC-17

Basic InspectionNBEC0038Precaution:
Perform Basic Inspection without electrical or mechanical
loads applied;
IHeadlamp switch is OFF,
IAir conditioner switch is OFF,
IRear window defogger switch is OFF,
ISteering wheel is in the straight-ahead position, etc.
1 INSPECTION START
1. Check service records for any recent repairs that may indicate a related problem, or a current need for scheduled
maintenance.
2. Open engine hood and check the following:
IHarness connectors for improper connections
IVacuum hoses for splits, kinks and improper connections
IWiring for improper connections, pinches and cuts
IAir cleaner clogging
IHoses and ducts for leaks
SEF983U
©GO TO 2.
2 CHECK THROTTLE OPENER OPERATION-I
Confirm that there is a clearance between throttle drum and stopper.
SEF950Y
OK or NG
OK©GO TO 4.
NG©GO TO 3.
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection
EC-101

Wiring DiagramNBEC0604
MEC421D
ELECTRICAL LOAD SIGNAL
Wiring Diagram
EC-644

ELECTRICAL SYSTEM
SECTION
EL
CONTENTS
PRECAUTIONS...............................................................4
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER²...............4
Wiring Diagrams and Trouble Diagnosis .....................4
HARNESS CONNECTOR................................................5
Description ...................................................................5
STANDARDIZED RELAY................................................7
Description ...................................................................7
POWER SUPPLY ROUTING...........................................9
Schematic ....................................................................9
Wiring Diagram - POWER - ......................................10
Inspection...................................................................16
GROUND........................................................................17
Ground Distribution ....................................................17
COMBINATION SWITCH..............................................28
Check .........................................................................28
Replacement ..............................................................29
STEERING SWITCH......................................................30
Check .........................................................................30
HEADLAMP (FOR USA) - XENON TYPE -..................31
Component Parts and Harness Connector
Location .....................................................................31
System Description ....................................................31
Schematic ..................................................................35
Wiring Diagram - H/LAMP -.......................................36
Trouble Diagnoses.....................................................40
Bulb Replacement/Xenon Type .................................43
Aiming Adjustment .....................................................44
HEADLAMP (FOR CANADA) - DAYTIME LIGHT
SYSTEM -......................................................................46
Component Parts and Harness Connector
Location .....................................................................46
System Description ....................................................46
Schematic ..................................................................50
Wiring Diagram - DTRL - ...........................................51
Trouble Diagnoses.....................................................56
Bulb Replacement .....................................................57
Aiming Adjustment .....................................................58
HEADLAMP - HEADLAMP AIMING CONTROL -........59System Description ....................................................59
Wiring Diagram - H/AIM - ..........................................60
PARKING, LICENSE AND TAIL LAMPS.....................61
System Description ....................................................61
Schematic ..................................................................62
Wiring Diagram - TAIL/L - ..........................................63
Trouble Diagnoses.....................................................66
STOP LAMP..................................................................67
Wiring Diagram - STOP/L - .......................................67
BACK-UP LAMP............................................................69
Wiring Diagram - BACK/L - .......................................69
FRONT FOG LAMP.......................................................70
System Description ....................................................70
Wiring Diagram - F/FOG - .........................................72
Aiming Adjustment .....................................................74
TURN SIGNAL AND HAZARD WARNING LAMPS.....75
System Description ....................................................75
Wiring Diagram - TURN - ..........................................77
Trouble Diagnoses.....................................................79
Electrical Components Inspection .............................79
ILLUMINATION..............................................................80
System Description ....................................................80
Schematic ..................................................................82
Wiring Diagram - ILL - ...............................................83
INTERIOR, SPOT, VANITY MIRROR AND
LUGGAGE ROOM LAMPS...........................................88
System Description ....................................................88
Schematic ..................................................................90
Wiring Diagram - INT/L - ...........................................91
METERS AND GAUGES...............................................94
Component Parts and Harness Connector
Location .....................................................................94
System Description ....................................................94
Combination Meter ....................................................96
Schematic ..................................................................98
Wiring Diagram - METER - .......................................99
Meter/Gauge Operation and Odo/Trip Meter
Segment Check in Diagnosis Mode ........................100
Trouble Diagnoses...................................................101
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Electrical Components Inspection ...........................108
COMPASS AND THERMOMETER............................. 110
System Description .................................................. 110
Wiring Diagram - COMPAS -................................... 111
Trouble Diagnoses................................................... 112
Calibration Procedure for Compass ........................ 113
WARNING LAMPS...................................................... 114
Schematic ................................................................ 114
Wiring Diagram - WARN - ....................................... 115
Fuel Warning Lamp Sensor Check .........................122
Electrical Components Inspection ...........................122
A/T INDICATOR...........................................................123
Wiring Diagram - AT/IND -.......................................123
WARNING CHIME.......................................................125
Component Parts and Harness Connector
Location ...................................................................125
System Description ..................................................125
Wiring Diagram - CHIME - ......................................127
Trouble Diagnoses...................................................129
FRONT WIPER AND WASHER..................................136
System Description ..................................................136
Wiring Diagram - WIPER - ......................................138
Removal and Installation .........................................139
Washer Nozzle Adjustment .....................................140
Washer Tube Layout ...............................................140
REAR WIPER AND WASHER....................................141
System Description ..................................................141
Wiring Diagram - WIP/R -........................................143
Trouble Diagnoses...................................................145
Removal and Installation .........................................145
Washer Nozzle Adjustment .....................................146
Washer Tube Layout ...............................................146
Check Valve .............................................................146
HORN...........................................................................147
Wiring Diagram - HORN - .......................................147
CIGARETTE LIGHTER................................................148
Wiring Diagram - CIGAR -.......................................148
CLOCK.........................................................................150
Wiring Diagram - CLOCK -......................................150
REAR WINDOW DEFOGGER.....................................151
Component Parts and Harness Connector
Location ...................................................................151
System Description ..................................................151
Wiring Diagram - DEF - ...........................................153
Trouble Diagnoses...................................................155
Electrical Components Inspection ...........................157
Filament Check ........................................................157
Filament Repair .......................................................158
AUDIO..........................................................................160
System Description ..................................................160
Schematic ................................................................161
Wiring Diagram - AUDIO - .......................................162Trouble Diagnoses...................................................166
Inspection.................................................................167
Wiring Diagram - REMOTE -...................................168
AUDIO ANTENNA.......................................................169
System Description ..................................................169
Wiring Diagram - P/ANT - .......................................170
Trouble Diagnoses...................................................171
Location of Antenna .................................................171
Antenna Rod Replacement .....................................171
POWER SUNROOF.....................................................173
System Description ..................................................173
Wiring Diagram - SROOF - .....................................174
Trouble Diagnoses...................................................176
DOOR MIRROR...........................................................177
Wiring Diagram - MIRROR - ...................................177
GLASS HATCH OPENER...........................................178
System Description ..................................................178
Wiring Diagram - TLID - ..........................................179
FUEL FILLER LID OPENER.......................................180
Wiring Diagram - F/LID - .........................................180
POWER SEAT.............................................................181
Wiring Diagram - SEAT - .........................................181
HEATED SEAT............................................................183
Wiring Diagram - HSEAT - ......................................183
Seatback Heating Unit .............................................185
AUTOMATIC DRIVE POSITIONER............................186
Component Parts and Harness Connector
Location ...................................................................186
System Description ..................................................187
Schematic ................................................................190
Wiring Diagram - AUT/DP - .....................................191
On Board Diagnosis ................................................196
Trouble Diagnoses...................................................198
AUTOMATIC SPEED CONTROL DEVICE (ASCD)...221
Component Parts and Harness Connector
Location ...................................................................221
System Description ..................................................222
Schematic ................................................................224
Wiring Diagram - ASCD - ........................................225
Fail-safe System ......................................................229
Trouble Diagnoses...................................................230
Electrical Component Inspection .............................239
ASCD Wire Adjustment ...........................................240
POWER WINDOW.......................................................241
System Description ..................................................241
Schematic ................................................................244
Wiring Diagram - WINDOW - ..................................245
Trouble Diagnoses...................................................250
POWER DOOR LOCK.................................................254
Component Parts and Harness Connector
Location ...................................................................254
System Description ..................................................254
CONTENTS(Cont'd)
EL-2

Schematic ................................................................255
Wiring Diagram - D/LOCK -.....................................256
Trouble Diagnoses...................................................261
MULTI-REMOTE CONTROL SYSTEM.......................270
Component Parts and Harness Connector
Location ...................................................................270
System Description ..................................................270
Schematic ................................................................273
Wiring Diagram - MULTI - .......................................274
Trouble Diagnoses...................................................277
ID Code Entry Procedure ........................................289
Remote Controller Battery Replacement.................293
THEFT WARNING SYSTEM.......................................294
Component Parts and Harness Connector
Location ...................................................................294
System Description ..................................................295
Schematic ................................................................298
Wiring Diagram - THEFT -.......................................300
Trouble Diagnoses...................................................306
SMART ENTRANCE CONTROL UNIT.......................319
Description ...............................................................319
Schematic ................................................................322
Smart Entrance Control Unit Inspection Table ........324
INTEGRATED HOMELINK TRANSMITTER...............325
Wiring Diagram - TRNSMT - ...................................325
Trouble Diagnoses...................................................326
IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM -
NATS)...........................................................................328
Component Parts and Harness Connetor
Location ...................................................................328
System Description ..................................................329
System Composition ................................................329
Wiring Diagram - NATS -.........................................330
CONSULT-II .............................................................331
Trouble Diagnoses...................................................334
How to Replace IVIS (NATS) IMMU .......................347
INFINITI COMMUNICATOR (IVCS)............................348
Precaution ................................................................348
Communicator Response Center Telephone
Number for Technicians ...........................................348
Component Parts and Harness Connector
Location ...................................................................349System Description ..................................................350
Schematic ................................................................358
Wiring Diagram - IVCS -..........................................359
CONSULT-II .............................................................363
Trouble Diagnoses...................................................368
Trouble Diagnoses for Intermittent Incident ............377
Demonstration Mode ...............................................379
System Setting (When IVCS Unit is Replaced) ......381
NAVIGATION SYSTEM...............................................385
Component Parts Location ......................................385
System Description ..................................................386
Schematic ................................................................393
Wiring Diagram - NAVI - ..........................................394
Self-diagnosis Mode ................................................397
Confirmation/Adjustment Mode ...............................400
Setting Mode............................................................410
Trouble diagnoses ...................................................417
This Condition is Not Abnormal ...............................423
Program Loading .....................................................432
Initialization ..............................................................433
ELECTRICAL UNITS LOCATION...............................436
Engine Compartment ...............................................436
Passenger Compartment .........................................438
HARNESS LAYOUT....................................................440
How to Read Harness Layout .................................440
Outline......................................................................441
Main Harness...........................................................442
Engine Room Harness ............................................444
Engine Control Harness ..........................................446
Body Harness LH ....................................................448
Body Harness RH ....................................................449
Back Door Harness .................................................450
Engine and Transmission Harness..........................451
Room Lamp Harness...............................................452
Air Bag Harness ......................................................453
Front Door Harness .................................................454
Rear Door Harness..................................................455
BULB SPECIFICATIONS............................................456
Headlamp.................................................................456
Exterior Lamp ..........................................................456
Interior Lamp............................................................456
WIRING DIAGRAM CODES (CELL CODES).............457GI
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CONTENTS(Cont'd)
EL-3