2001 INFINITI QX4 diagram

MBR439A
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DESCRIPTIONABS
Wiring Diagram Ð ABS Ð (Cont'd)
BR-39

MBR440A
DESCRIPTIONABS
Wiring Diagram Ð ABS Ð (Cont'd)
BR-40

Removal and InstallationNBBT0014IWhen removing or installing the seat trim, carefully handle it to keep dirt out and avoid damage.
HFor Wiring Diagram, refer to EL-181, ªPOWER SEATº for details.
CAUTION:
IBefore removing the front seat, turn the ignition switch off, disconnect both battery cables and wait
at least 3 minutes.
IWhen checking the power seat circuit for continuity using a circuit tester, do not confuse its con-
nector with the side air bag module connector. Such an error may cause the air bag to deploy.
IDo not drop, tilt, or bump the side air bag module installed in the seat. Always handle it with care.
SBT066A
SBT067A
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FRONT SEAT
Removal and Installation
BT-41

HEATED SEAT=NBBT0014S03IWhen handling seat, be extremely careful not to scratch heating unit.
ITo replace heating unit, seat trim and pad should be separated.
IDo not use any organic solvent, such as thinner, benzene, alcohol, gasoline, etc. to clean trims.
HFor Wiring Diagram, refer to EL-183, ªHEATED SEATº for details.
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FRONT SEAT
Removal and Installation (Cont'd)
BT-43

Removal and InstallationNBBT0020CAUTION:
Be careful not to scratch door rearview mirror body.
HFor Wiring Diagram, refer to EL-177, ªDOOR MIRRORº for details.
1. Remove door trim. Refer to ªDOOR TRIMº for details, BT-30.
2. Remove clip securing inner cover from front corner of door.
3. Disconnect door mirror harness connector.
4. Remove bolts securing door mirror, then remove door mirror assembly.
SBT891
DOOR MIRROR
Removal and Installation
BT-56

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 ........................................................................150
ECM Terminals and Reference Value .....................150
On Board Diagnosis Logic.......................................151
Possible Cause ........................................................151
DTC Confirmation Procedure ..................................151
Overall Function Check ...........................................153
Wiring Diagram ........................................................154
Diagnostic Procedure ..............................................155
DTC P0105 ABSOLUTE PRESSURE SENSOR........158
Component Description ...........................................158
ECM Terminals and Reference Value .....................158
On Board Diagnosis Logic.......................................158
Possible Cause ........................................................159
DTC Confirmation Procedure ..................................159
Wiring Diagram ........................................................160
Diagnostic Procedure ..............................................161
DTC P0110 INTAKE AIR TEMPERATURE
SENSOR......................................................................164
Component Description ...........................................164
On Board Diagnosis Logic.......................................164
Possible Cause ........................................................164
DTC Confirmation Procedure ..................................164
Wiring Diagram ........................................................166
Diagnostic Procedure ..............................................167
DTC P0115 ENGINE COOLANT TEMPERATURE
SENSOR (ECTS) (CIRCUIT).......................................169
Component Description ...........................................169
On Board Diagnosis Logic.......................................169
Possible Cause ........................................................170
DTC Confirmation Procedure ..................................170
Wiring Diagram ........................................................171
Diagnostic Procedure ..............................................172
DTC P0120 THROTTLE POSITION SENSOR...........174
Description ...............................................................174
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................174
ECM Terminals and Reference Value .....................175
On Board Diagnosis Logic.......................................175
Possible Cause ........................................................175
DTC Confirmation Procedure ..................................176
Wiring Diagram ........................................................180
Diagnostic Procedure ..............................................181
DTC P0125 ENGINE COOLANT TEMPERATURE
SENSOR (ECTS).........................................................187
Description ...............................................................187
On Board Diagnosis Logic.......................................187
Possible Cause ........................................................188
DTC Confirmation Procedure ..................................188
Wiring Diagram ........................................................189
Diagnostic Procedure ..............................................190DTC P0130, P0150 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (CIRCUIT)..................192
Component Description ...........................................192
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................192
ECM Terminals and Reference Value .....................192
On Board Diagnosis Logic.......................................193
Possible Cause ........................................................193
DTC Confirmation Procedure ..................................194
Overall Function Check ...........................................194
Wiring Diagram ........................................................196
Diagnostic Procedure ..............................................198
DTC P0131, P0151 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (LEAN SHIFT
MONITORING).............................................................202
Component Description ...........................................202
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................202
ECM Terminals and Reference Value .....................202
On Board Diagnosis Logic.......................................203
Possible Cause ........................................................203
DTC Confirmation Procedure ..................................203
Overall Function Check ...........................................204
Diagnostic Procedure ..............................................205
DTC P0132, P0152 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (RICH SHIFT
MONITORING).............................................................210
Component Description ...........................................210
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................210
ECM Terminals and Reference Value .....................210
On Board Diagnosis Logic....................................... 211
Possible Cause ........................................................ 211
DTC Confirmation Procedure .................................. 211
Overall Function Check ...........................................212
Diagnostic Procedure ..............................................213
DTC P0133, P0153 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (RESPONSE
MONITORING).............................................................218
Component Description ...........................................218
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................218
ECM Terminals and Reference Value .....................218
On Board Diagnosis Logic.......................................219
Possible Cause ........................................................219
DTC Confirmation Procedure ..................................220
Overall Function Check ...........................................221
Wiring Diagram ........................................................222
Diagnostic Procedure ..............................................224
DTC P0134, P0154 HEATED OXYGEN SENSOR 1
(FRONT) (BANK 1)/(BANK 2) (HIGH VOLTAGE)......231
Component Description ...........................................231
CONTENTS(Cont'd)
EC-2

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