2001 INFINITI QX4 Ac system

BODY & TRIM
SECTION
BT
CONTENTS
PRECAUTIONS...............................................................2
Service Notice..............................................................2
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER²...............2
PREPARATION...............................................................3
Special Service Tools ..................................................3
Commercial Service Tools ...........................................3
SQUEAK AND RATTLE TROUBLE DIAGNOSES.........4
Work Flow ....................................................................4
CUSTOMER INTERVIEW...........................................4
DUPLICATE THE NOISE AND TEST DRIVE................5
CHECK RELATED SERVICE BULLETINS...................5
LOCATE THE NOISE AND IDENTIFY THE ROOT
CAUSE
.....................................................................5
REPAIR THE CAUSE.................................................5
CONFIRM THE REPAIR.............................................6
Generic Squeak and Rattle Troubleshooting ..............6
INSTRUMENT PANEL................................................6
CENTER CONSOLE..................................................6
DOORS.....................................................................6
TRUNK.....................................................................7
SUNROOF/HEADLINER.............................................7
SEATS......................................................................7
UNDERHOOD...........................................................7
Diagnostic Worksheet ..................................................8
CLIP AND FASTENER..................................................10
Description .................................................................10
BODY FRONT END.......................................................12
Removal and Installation ...........................................12
FRONT BUMPER ASSEMBLY..................................12
BODY REAR END AND OPENER................................15
Removal and Installation ...........................................15
REAR BUMPER ASSEMBLY....................................15
FRONT DOOR...............................................................18
Overhaul ....................................................................18
Front Door Limit Switch Reset ..................................19
RESET CONDITIONS..............................................19
RESET PROCEDURES............................................19
REAR DOOR.................................................................20
Overhaul ....................................................................20INSTRUMENT PANEL ASSEMBLY.............................21
Removal and Installation ...........................................21
SIDE AND FLOOR TRIM...............................................28
Removal and Installation ...........................................28
DOOR TRIM...................................................................30
Removal and Installation ...........................................30
ROOF TRIM...................................................................32
Removal and Installation ...........................................32
BACK DOOR TRIM.......................................................34
Removal and Installation ...........................................34
EXTERIOR.....................................................................35
Removal and Installation ...........................................35
FRONT SEAT................................................................41
Removal and Installation ...........................................41
HEATED SEAT........................................................43
REAR SEAT...................................................................44
Removal and Installation ...........................................44
SUNROOF......................................................................45
Adjustment .................................................................45
Removal and Installation ...........................................45
Trouble Diagnoses.....................................................49
DIAGNOSTIC TABLE................................................49
WIND DEFLECTOR.................................................49
ADJUSTMENT.........................................................50
DRAIN HOSES........................................................51
WEATHERSTRIP.....................................................51
LINK AND WIRE ASSEMBLY....................................52
WINDSHIELD AND WINDOWS....................................53
Removal and Installation ...........................................53
REMOVAL...............................................................53
INSTALLATION........................................................53
WINDSHIELD..........................................................54
REAR SIDE WINDOW..............................................55
DOOR MIRROR.............................................................56
Removal and Installation ...........................................56
BODY (ALIGNMENT)....................................................57
Alignment ...................................................................57
ENGINE COMPARTMENT........................................58
UNDERBODY..........................................................60
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Service NoticeNBBT0001IWhen removing or installing various parts, place a cloth or padding onto the vehicle body to prevent
scratches.
IHandle trim, molding, instruments, grille, etc. carefully during removing or installing. Be careful not to soil
or damage them.
IApply sealing compound where necessary when installing parts.
IWhen applying sealing compound, be careful that the sealing compound does not protrude from parts.
IWhen replacing any metal parts (for example body outer panel, members, etc.), be sure to take rust pre-
vention measures.
Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBBT0002The 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
Service Notice
BT-2

Removal and InstallationNBBT0005IBumper fascia is made of plastic. Do not use excessive force and be sure to keep oil away from it.
IBack door lock system adjustment: Adjust lock & striker so that they are in the center.
After adjustment, check back door lock operation.
IBack door hatch lock system adjustment: Adjust lock & striker so that they are in the center.
After adjustment, check back door hatch lock operation.
WARNING:
IBe careful not to scratch back door stay and/or back door hatch stay when installing back door
and/or back door hatch. A scratched stay may cause gas leakage.
IThe contents of the back door stay and back door hatch stay are under pressure. Do not take apart,
puncture, apply heat or allow fire near them.
REAR BUMPER ASSEMBLYNBBT0005S011. Remove bolts and screws securing left and right mudguards and remove the mudguards.
2. Remove clips and screws securing left and right sides of wheel protector.
3. Remove clips and bolts securing left and right rear fenders to bumper fascia.
4. Remove bolts securing bumper reinforcement to bumper fascia.
5. Remove clips securing bumper fascia.
6. Extract bumper fascia assembly.
7. Remove bolts and nuts securing bumper reinforcement.
8. Extract bumper reinforcement.
SBT715
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BODY REAR END AND OPENER
Removal and Installation
BT-15

Removal and InstallationNBBT0008CAUTION:
IDisconnect both battery cables in advance.
IDisconnect air bag system line in advance.
INever tamper with or force air bag lid open, as this may
adversely affect air bag performance.
IBe careful not to scratch pad and other parts.
SBT042A
*1 RS-17 *2 BT-28
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INSTRUMENT PANEL ASSEMBLY
Removal and Installation
BT-21

ENGINE CONTROL SYSTEM
SECTION
EC
CONTENTS
TROUBLE DIAGNOSIS - INDEX....................................8
Alphabetical & P No. Index for DTC ...........................8
PRECAUTIONS.............................................................14
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER².............14
Precautions for On Board Diagnostic (OBD)
System of Engine and A/T.........................................14
Engine Fuel & Emission Control System ..................15
Precautions ................................................................16
Wiring Diagrams and Trouble Diagnosis ...................17
PREPARATION.............................................................18
Special Service Tools ................................................18
Commercial Service Tools .........................................18
ENGINE AND EMISSION CONTROL OVERALL
SYSTEM.........................................................................20
Engine Control Component Parts Location ...............20
Circuit Diagram ..........................................................24
System Diagram ........................................................25
Vacuum Hose Drawing ..............................................26
System Chart .............................................................27
ENGINE AND EMISSION BASIC CONTROL
SYSTEM DESCRIPTION...............................................28
Multiport Fuel Injection (MFI) System .......................28
Electronic Ignition (EI) System ..................................30
Air Conditioning Cut Control ......................................31
Fuel Cut Control (at no load & high engine
speed) ........................................................................32
Evaporative Emission System ...................................32
Positive Crankcase Ventilation ..................................38
BASIC SERVICE PROCEDURE...................................39
Fuel Pressure Release ..............................................39
Fuel Pressure Check .................................................39
Fuel Pressure Regulator Check ................................40
Injector .......................................................................41
How to Check Idle Speed and Ignition Timing ..........42
Idle Speed/Ignition Timing/Idle Mixture Ratio
Adjustment .................................................................43
Idle Air Volume Learning ...........................................57ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION...............................................................59
Introduction ................................................................59
Two Trip Detection Logic ...........................................59
Emission-related Diagnostic Information ...................60
Malfunction Indicator Lamp (MIL) ..............................74
OBD System Operation Chart ...................................75
CONSULT-II ...............................................................81
Generic Scan Tool (GST) ..........................................95
TROUBLE DIAGNOSIS - INTRODUCTION..................97
Introduction ................................................................97
Work Flow ..................................................................99
TROUBLE DIAGNOSIS - BASIC INSPECTION.........101
Basic Inspection.......................................................101
TROUBLE DIAGNOSIS - GENERAL
DESCRIPTION............................................................. 116
DTC Inspection Priority Chart.................................. 116
Fail-safe Chart ......................................................... 117
Symptom Matrix Chart ............................................. 118
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................122
Major Sensor Reference Graph in Data Monitor
Mode ........................................................................124
ECM Terminals and Reference Value .....................127
TROUBLE DIAGNOSIS - SPECIFICATION VALUE..136
Description ...............................................................136
Testing Condition .....................................................136
Inspection Procedure ...............................................136
Diagnostic Procedure ..............................................137
TROUBLE DIAGNOSIS FOR INTERMITTENT
INCIDENT.....................................................................140
Description ...............................................................140
Diagnostic Procedure ..............................................140
TROUBLE DIAGNOSIS FOR POWER SUPPLY........141
ECM Terminals and Reference Value .....................141
Main Power Supply and Ground Circuit ..................142
DTC P0100 MASS AIR FLOW SENSOR (MAFS)......150
Component Description ...........................................150
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CONSULT-II Reference Value in Data Monitor
Mode ........................................................................231
ECM Terminals and Reference Value .....................231
On Board Diagnosis Logic.......................................232
Possible Cause ........................................................232
DTC Confirmation Procedure ..................................232
Wiring Diagram ........................................................234
Diagnostic Procedure ..............................................236
DTC P0135, P0155 HEATED OXYGEN SENSOR 1
HEATER (FRONT) (BANK 1)/(BANK 2).....................240
Description ...............................................................240
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................240
ECM Terminals and Reference Value .....................240
On Board Diagnosis Logic.......................................241
Possible Cause ........................................................241
DTC Confirmation Procedure ..................................241
Wiring Diagram ........................................................242
Diagnostic Procedure ..............................................244
DTC P0137, P0157 HEATED OXYGEN SENSOR 2
(REAR) (BANK 1)/(BANK 2) (MIN. VOLTAGE
MONITORING).............................................................247
Component Description ...........................................247
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................247
ECM Terminals and Reference Value .....................247
On Board Diagnosis Logic.......................................247
Possible Cause ........................................................248
DTC Confirmation Procedure ..................................248
Overall Function Check ...........................................248
Wiring Diagram ........................................................250
Diagnostic Procedure ..............................................252
DTC P0138, P0158 HEATED OXYGEN SENSOR 2
(REAR) (BANK 1)/(BANK 2) (MAX. VOLTAGE
MONITORING).............................................................257
Component Description ...........................................257
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................257
ECM Terminals and Reference Value .....................257
On Board Diagnosis Logic.......................................257
Possible Cause ........................................................258
DTC Confirmation Procedure ..................................258
Overall Function Check ...........................................258
Wiring Diagram ........................................................260
Diagnostic Procedure ..............................................262
DTC P0139, P0159 HEATED OXYGEN SENSOR 2
(REAR) (BANK 1)/(BANK 2) (RESPONSE
MONITORING).............................................................267
Component Description ...........................................267
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................267
ECM Terminals and Reference Value .....................267On Board Diagnosis Logic.......................................267
Possible Cause ........................................................268
DTC Confirmation Procedure ..................................268
Overall Function Check ...........................................268
Wiring Diagram ........................................................270
Diagnostic Procedure ..............................................272
DTC P0140, P0160 HEATED OXYGEN SENSOR 2
(REAR) (BANK 1)/(BANK 2) (HIGH VOLTAGE)........277
Component Description ...........................................277
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................277
ECM Terminals and Reference Value .....................277
On Board Diagnosis Logic.......................................277
Possible Cause ........................................................278
DTC Confirmation Procedure ..................................278
Overall Function Check ...........................................278
Wiring Diagram ........................................................280
Diagnostic Procedure ..............................................282
DTC P0141, P0161 HEATED OXYGEN SENSOR 2
HEATER (REAR) (BANK 1)/(BANK 2).......................286
Description ...............................................................286
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................286
ECM Terminals and Reference Value .....................286
On Board Diagnosis Logic.......................................287
Possible Cause ........................................................287
DTC Confirmation Procedure ..................................287
Wiring Diagram ........................................................289
Diagnostic Procedure ..............................................291
DTC P0171 (RIGHT, -B1), P0174 (LEFT, -B2)
FUEL INJECTION SYSTEM FUNCTION (LEAN).......294
On Board Diagnosis Logic.......................................294
Possible Cause ........................................................294
DTC Confirmation Procedure ..................................294
Wiring Diagram ........................................................296
Diagnostic Procedure ..............................................298
DTC P0172 (RIGHT, -B1), P0175 (LEFT, -B2)
FUEL INJECTION SYSTEM FUNCTION (RICH)........302
On Board Diagnosis Logic.......................................302
Possible Cause ........................................................302
DTC Confirmation Procedure ..................................302
Wiring Diagram ........................................................304
Diagnostic Procedure ..............................................306
DTC P0180 FUEL TANK TEMPERATURE
SENSOR......................................................................309
Component Description ...........................................309
On Board Diagnosis Logic.......................................309
Possible Cause ........................................................309
DTC Confirmation Procedure ..................................310
Wiring Diagram ........................................................ 311
Diagnostic Procedure ..............................................312GI
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CONTENTS(Cont'd)
EC-3

DTC P0217 COOLANT OVERTEMPERATURE
ENRICHMENT PROTECTION.....................................314
On Board Diagnosis Logic.......................................314
Possible Cause ........................................................314
Overall Function Check ...........................................314
Diagnostic Procedure ..............................................316
Main 12 Causes of Overheating..............................319
DTC P0300 - P0306 NO.6-1CYLINDER
MISFIRE, MULTIPLE CYLINDER MISFIRE...............320
On Board Diagnosis Logic.......................................320
Possible Cause ........................................................320
DTC Confirmation Procedure ..................................321
Diagnostic Procedure ..............................................321
DTC P0325 KNOCK SENSOR (KS)...........................328
Component Description ...........................................328
ECM Terminals and Reference Value .....................328
On Board Diagnosis Logic.......................................328
Possible Cause ........................................................328
DTC Confirmation Procedure ..................................328
Wiring Diagram ........................................................330
Diagnostic Procedure ..............................................331
DTC P0335 CRANKSHAFT POSITION SENSOR
(CKPS) (POS)..............................................................334
Component Description ...........................................334
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................334
ECM Terminals and Reference Value .....................335
On Board Diagnosis Logic.......................................335
Possible Cause ........................................................335
DTC Confirmation Procedure ..................................336
Wiring Diagram ........................................................337
Diagnostic Procedure ..............................................338
DTC P0340 CAMSHAFT POSITION SENSOR
(CMPS) (PHASE).........................................................342
Component Description ...........................................342
ECM Terminals and Reference Value .....................342
On Board Diagnosis Logic.......................................342
Possible Cause ........................................................343
DTC Confirmation Procedure ..................................343
Wiring Diagram ........................................................344
Diagnostic Procedure ..............................................345
DTC P0420 (RIGHT BANK, -B1), P0430 (LEFT
BANK, -B2) THREE WAY CATALYST FUNCTION...347
On Board Diagnosis Logic.......................................347
Possible Cause ........................................................347
DTC Confirmation Procedure ..................................348
Overall Function Check ...........................................348
Diagnostic Procedure ..............................................349
DTC P0440 EVAP CONTROL SYSTEM (SMALL
LEAK) (NEGATIVE PRESSURE)................................352
On Board Diagnosis Logic.......................................352
Possible Cause ........................................................352DTC Confirmation Procedure ..................................354
Diagnostic Procedure ..............................................355
DTC P0443 EVAP CANISTER PURGE VOLUME
CONTROL SOLENOID VALVE (CIRCUIT).................367
Description ...............................................................367
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................367
ECM Terminals and Reference Value .....................368
On Board Diagnosis Logic.......................................368
Possible Cause ........................................................368
DTC Confirmation Procedure ..................................369
Wiring Diagram ........................................................370
Diagnostic Procedure ..............................................371
DTC P0446 EVAPORATIVE EMISSION (EVAP)
CANISTER VENT CONTROL VALVE (CIRCUIT)......374
Component Description ...........................................374
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................374
ECM Terminals and Reference Value .....................374
On Board Diagnosis Logic.......................................374
Possible Cause ........................................................375
DTC Confirmation Procedure ..................................375
Wiring Diagram ........................................................376
Diagnostic Procedure ..............................................377
DTC P0450 EVAPORATIVE EMISSION (EVAP)
CONTROL SYSTEM PRESSURE SENSOR..............381
Component Description ...........................................381
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................381
ECM Terminals and Reference Value .....................381
On Board Diagnosis Logic.......................................382
Possible Cause ........................................................382
DTC Confirmation Procedure ..................................382
Wiring Diagram ........................................................384
Diagnostic Procedure ..............................................385
DTC P0455 EVAP CONTROL SYSTEM (GROSS
LEAK)...........................................................................394
On Board Diagnosis Logic.......................................394
Possible Cause ........................................................394
DTC Confirmation Procedure ..................................396
Diagnostic Procedure ..............................................397
DTC P0460 FUEL LEVEL SENSOR FUNCTION
(SLOSH).......................................................................407
Component Description ...........................................407
On Board Diagnostic Logic......................................407
Possible Cause ........................................................407
DTC Confirmation Procedure ..................................407
Wiring Diagram ........................................................408
Diagnostic Procedure ..............................................409
DTC P0461 FUEL LEVEL SENSOR FUNCTION....... 411
Component Description ........................................... 411
On Board Diagnostic Logic...................................... 411
CONTENTS(Cont'd)
EC-4

Possible Cause ........................................................ 411
Overall Function Check ........................................... 411
DTC P0464 FUEL LEVEL SENSOR CIRCUIT...........413
Component Description ...........................................413
On Board Diagnostic Logic......................................413
Possible Cause ........................................................413
DTC Confirmation Procedure ..................................413
Wiring Diagram ........................................................414
Diagnostic Procedure ..............................................415
DTC P0500 VEHICLE SPEED SENSOR (VSS).........417
Component Description ...........................................417
ECM Terminals and Reference Value .....................417
On Board Diagnosis Logic.......................................417
Possible Cause ........................................................418
DTC Confirmation Procedure ..................................418
Overall Function Check ...........................................418
Wiring Diagram ........................................................420
Diagnostic Procedure ..............................................421
DTC P0505 IDLE AIR CONTROL VALVE (IACV) -
AUXILIARY AIR CONTROL (AAC) VALVE...............422
Description ...............................................................422
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................423
ECM Terminals and Reference Value .....................423
On Board Diagnosis Logic.......................................423
Possible Cause ........................................................423
DTC Confirmation Procedure ..................................423
Wiring Diagram ........................................................425
Diagnostic Procedure ..............................................426
DTC P0510 CLOSED THROTTLE POSITION
SWITCH.......................................................................431
Component Description ...........................................431
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................431
ECM Terminals and Reference Value .....................431
On Board Diagnosis Logic.......................................431
Possible Cause ........................................................431
DTC Confirmation Procedure ..................................432
Overall Function Check ...........................................432
Wiring Diagram ........................................................434
Diagnostic Procedure ..............................................435
DTC P0600 A/T COMMUNICATION LINE..................440
System Description ..................................................440
ECM Terminals and Reference Value .....................440
On Board Diagnosis Logic.......................................440
Possible Cause ........................................................440
DTC Confirmation Procedure ..................................440
Wiring Diagram ........................................................442
Diagnostic Procedure ..............................................443
DTC P0605 ECM.........................................................444
Component Description ...........................................444
On Board Diagnosis Logic.......................................444Possible Cause ........................................................444
DTC Confirmation Procedure ..................................444
Diagnostic Procedure ..............................................445
DTC P1110 (RIGHT, -B1), P1135 (LEFT, -B2)
INTAKE VALVE TIMING CONTROL..........................446
Description ...............................................................446
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................446
ECM Terminals and Reference Value .....................447
On Board Diagnosis Logic.......................................448
Possible Cause ........................................................448
DTC Confirmation Procedure ..................................449
D T C P 1111(RIGHT, -B1), P1136 (LEFT, -B2)
INTAKE VALVE TIMING CONTROL SOLENOID
VALVE (CIRCUIT)........................................................451
Component Description ...........................................451
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................451
ECM Terminals and Reference Value .....................451
On Board Diagnosis Logic.......................................452
Possible Cause ........................................................452
DTC Confirmation Procedure ..................................452
Wiring Diagram ........................................................453
Diagnostic Procedure ..............................................455
DTC P1130 SWIRL CONTROL VALVE CONTROL
SOLENOID VALVE......................................................458
Description ...............................................................458
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................459
ECM Terminals and Reference Value .....................459
On Board Diagnosis Logic.......................................459
Possible Cause ........................................................460
DTC Confirmation Procedure ..................................460
Wiring Diagram ........................................................462
Diagnostic Procedure ..............................................463
DTC P1140 (RIGHT, -B1), P1145 (LEFT, -B2)
INTAKE VALVE TIMING CONTROL POSITION
SENSOR (CIRCUIT)....................................................482
Component Description ...........................................482
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................482
ECM Terminals and Reference Value .....................482
On Board Diagnosis Logic.......................................483
Possible Cause ........................................................483
DTC Confirmation Procedure ..................................483
Wiring Diagram ........................................................485
Diagnostic Procedure ..............................................487
DTC P1148 (RIGHT BANK, -B1), P1168 (LEFT
BANK, -B2) CLOSED LOOP CONTROL...................491
On Board Diagnosis Logic.......................................491
Possible Cause ........................................................491
DTC Confirmation Procedure ..................................491GI
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CONTENTS(Cont'd)
EC-5