elec INFINITI QX4 2001 Factory Service Manual

EDITION: FEBRUARY 2000
REVISION: FEBRUARY 2001
PUBLICATION NO. SM1E-1J50U5
QUICK REFERENCE INDEX
All rights reserved. No part of this Service Manual may be reproduced or stored in a retrieval system, or transmitted in any form, or
by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of Nissan Motor
Company Ltd., Tokyo, Japan.

FOREWORD
This manual contains maintenance and repair procedures for the
2001 INFINITI QX4.
In order to assure your safety and the efficient functioning of the
vehicle, this manual should be read thoroughly. It is especially
important that the PRECAUTIONS in the GI section be completely
understood before starting any repair task.
All information in this manual is based on the latest product infor-
mation at the time of publication. The right is reserved to make
changes in specifications and methods at any time without notice.
IMPORTANT SAFETY NOTICE
The proper performance of service is essential for both the safety of
the technician and the efficient functioning of the vehicle.
The service methods in this Service Manual are described in such a
manner that the service may be performed safely and accurately.
Service varies with the procedures used, the skills of the technician
and the tools and parts available. Accordingly, anyone using service
procedures, tools or parts which are not specifically recommended
by INFINITI must first be completely satisfied that neither personal
safety nor the vehicle's safety will be jeopardized by the service
method selected.

AUTOMATIC TRANSMISSION
SECTION
AT
CONTENTS
TROUBLE DIAGNOSIS - INDEX....................................4
Alphabetical & P No. Index for DTC ...........................4
PRECAUTIONS...............................................................6
Precautions for Supplemental Restraint System
(SRS)²AIR BAG²and²SEAT BELT
PRE-TENSIONER²......................................................6
Precautions for On Board Diagnostic (OBD)
System of A/T and Engine...........................................6
Precautions ..................................................................6
Service Notice or Precautions .....................................8
Wiring Diagrams and Trouble Diagnosis .....................9
PREPARATION.............................................................10
Special Service Tools ................................................10
OVERALL SYSTEM......................................................12
A/T Electrical Parts Location .....................................12
Circuit Diagram ..........................................................13
Cross-sectional View .................................................14
Hydraulic Control Circuit ............................................15
Shift Mechanism ........................................................16
Control System ..........................................................25
Control Mechanism ....................................................26
Control Valve .............................................................31
ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION...............................................................33
Introduction ................................................................33
OBD-II Function for A/T System ................................33
One or Two Trip Detection Logic of OBD-II ..............33
OBD-II Diagnostic Trouble Code (DTC) ....................33
Malfunction Indicator Lamp (MIL) ..............................37
CONSULT-II ...............................................................37
Diagnostic Procedure Without CONSULT-II ..............46
TROUBLE DIAGNOSIS - INTRODUCTION..................53
Introduction ................................................................53
Work Flow ..................................................................57
TROUBLE DIAGNOSIS - BASIC INSPECTION...........59
A/T Fluid Check .........................................................59
Stall Test ....................................................................59
Line Pressure Test .....................................................62
Road Test...................................................................63TROUBLE DIAGNOSIS - GENERAL
DESCRIPTION...............................................................81
Symptom Chart ..........................................................81
TCM Terminals and Reference Value........................92
TROUBLE DIAGNOSIS FOR POWER SUPPLY..........96
Wiring Diagram - AT - MAIN ......................................96
Diagnostic Procedure ................................................97
DTC P0705 PARK/NEUTRAL POSITION SWITCH.....99
Description .................................................................99
Wiring Diagram - AT - PNP/SW...............................101
Diagnostic Procedure ..............................................102
Component Inspection .............................................103
DTC P0710 A/T FLUID TEMPERATURE SENSOR
CIRCUIT.......................................................................105
Description ...............................................................105
Wiring Diagram - AT - FTS ......................................107
Diagnostic Procedure ..............................................108
Component Inspection ............................................. 110
DTC P0720 VEHICLE SPEED SENSOR.A/T
(REVOLUTION SENSOR)........................................... 111
Description ............................................................... 111
Wiring Diagram - AT - VSSA/T ................................ 113
Diagnostic Procedure .............................................. 114
Component Inspection ............................................. 115
DTC P0725 ENGINE SPEED SIGNAL....................... 116
Description ............................................................... 116
Wiring Diagram - AT - ENGSS ................................ 117
Diagnostic Procedure .............................................. 118
DTC P0731 IMPROPER SHIFTING TO 1ST GEAR
POSITION....................................................................120
Description ...............................................................120
Wiring Diagram - AT - 1ST ......................................123
Diagnostic Procedure ..............................................124
Component Inspection .............................................125
DTC P0732 IMPROPER SHIFTING TO 2ND GEAR
POSITION....................................................................126
Description ...............................................................126
Wiring Diagram - AT - 2ND......................................129
Diagnostic Procedure ..............................................130
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Component Inspection .............................................131
DTC P0733 IMPROPER SHIFTING TO 3RD GEAR
POSITION....................................................................132
Description ...............................................................132
Wiring Diagram - AT - 3RD......................................135
Diagnostic Procedure ..............................................136
Component Inspection .............................................137
DTC P0734 IMPROPER SHIFTING TO 4TH GEAR
POSITION....................................................................138
Description ...............................................................138
Wiring Diagram - AT - 4TH ......................................142
Diagnostic Procedure ..............................................143
Component Inspection .............................................147
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE......................................................148
Description ...............................................................148
Wiring Diagram - AT - TCV......................................150
Diagnostic Procedure ..............................................151
Component Inspection .............................................152
DTC P0744 IMPROPER LOCK-UP OPERATION......153
Description ...............................................................153
Wiring Diagram - AT - TCCSIG ...............................156
Diagnostic Procedure ..............................................157
Component Inspection .............................................161
DTC P0745 LINE PRESSURE SOLENOID VALVE...162
Description ...............................................................162
Wiring Diagram - AT - LPSV....................................164
Diagnostic Procedure ..............................................165
Component Inspection .............................................167
DTC P0750 SHIFT SOLENOID VALVE A..................168
Description ...............................................................168
Wiring Diagram - AT - SSV/A ..................................169
Diagnostic Procedure ..............................................170
Component Inspection .............................................171
DTC P0755 SHIFT SOLENOID VALVE B..................172
Description ...............................................................172
Wiring Diagram - AT - SSV/B ..................................173
Diagnostic Procedure ..............................................174
Component Inspection .............................................175
DTC P1705 THROTTLE POSITION SENSOR...........176
Description ...............................................................176
Wiring Diagram - AT - TPS ......................................179
Diagnostic Procedure ..............................................180
Component Inspection .............................................184
DTC P1760 OVERRUN CLUTCH SOLENOID
VALVE..........................................................................185
Description ...............................................................185
Wiring Diagram - AT - OVRCSV..............................187
Diagnostic Procedure ..............................................188
Component Inspection .............................................189
DTC BATT/FLUID TEMP SEN (A/T FLUID TEMP
SENSOR CIRCUIT AND TCM POWER SOURCE)....190Description ...............................................................190
Wiring Diagram - AT - BA/FTS ................................192
Diagnostic Procedure ..............................................193
Component Inspection .............................................196
DTC VEHICLE SPEED SENSOR.MTR.......................197
Description ...............................................................197
Wiring Diagram - AT - VSSMTR ..............................199
Diagnostic Procedure ..............................................200
DTC TURBINE REVOLUTION SENSOR....................202
Description ...............................................................202
Wiring Diagram - AT - TRSA/T ................................204
Diagnostic Procedure ..............................................205
Component Inspection .............................................206
DTC A/T COMMUNICATION LINE.............................207
Description ...............................................................207
Wiring Diagram - AT - LAN ......................................209
Diagnostic Procedure ..............................................210
DTC CONTROL UNIT (RAM), CONTROL UNIT
(ROM)........................................................................... 211
Description ............................................................... 211
Diagnostic Procedure ..............................................212
DTC CONTROL UNIT (EEP ROM).............................213
Description ...............................................................213
Diagnostic Procedure ..............................................214
TROUBLE DIAGNOSES FOR SYMPTOMS...............215
Wiring Diagram - AT - NONDTC .............................215
1. O/D OFF Indicator Lamp Does Not Come On....218
2. Engine Cannot Be Started In²P²and²N²
Position ....................................................................221
3. In²P²Position, Vehicle Moves Forward Or
Backward When Pushed .........................................222
4. In²N²Position, Vehicle Moves ...........................223
5. Large Shock.²N²->²R²Position .......................225
6. Vehicle Does Not Creep Backward In²R²
Position ....................................................................227
7. Vehicle Does Not Creep Forward In²D²,²2²
Or²1²Position .........................................................230
8. Vehicle Cannot Be Started From D
1...................233
9. A/T Does Not Shift: D
1-> D2Or Does Not
Kickdown: D
4-> D2..................................................236
10. A/T Does Not Shift: D
2-> D3.............................239
11. A/T Does Not Shift: D
3-> D4.............................242
12. A/T Does Not Perform Lock-up .........................245
13. A/T Does Not Hold Lock-up Condition ..............247
14. Lock-up Is Not Released ...................................249
15. Engine Speed Does Not Return To Idle (Light
Braking D
4-> D3).....................................................250
16. Vehicle Does Not Start From D
1.......................252
17. A/T Does Not Shift: D
4-> D3, When
Overdrive Control Switch²ON²->²OFF²...............253
18. A/T Does Not Shift: D
3-> 22, When Selector
Lever²D²->²2²Position.........................................254
CONTENTS(Cont'd)
AT-2

19. A/T Does Not Shift: 22-> 11, When Selector
Lever²2²->²1²Position .........................................255
20. Vehicle Does Not Decelerate By Engine
Brake........................................................................256
21. TCM Self-diagnosis Does Not Activate (PNP,
Overdrive Control and Throttle Position Switches
Circuit Checks) ........................................................257
A/T SHIFT LOCK SYSTEM.........................................265
Description ...............................................................265
Wiring Diagram - SHIFT -........................................266
Diagnostic Procedure ..............................................267
KEY INTERLOCK CABLE..........................................271
Components.............................................................271
Removal ...................................................................271
Installation ................................................................272
ON-VEHICLE SERVICE..............................................273
Control Valve Assembly and Accumulators .............273
Revolution Sensor Replacement .............................274
Turbine Revolution Sensor Replacement................274
Rear Oil Seal Replacement .....................................274
Rear Oil Seal and Companion Flange Oil Seal
Replacement ............................................................275
Parking Components Inspection..............................275
Park/Neutral Position Switch Adjustment ................276
Manual Control Linkage Adjustment........................276
REMOVAL AND INSTALLATION...............................277
Removal ...................................................................277
Installation ................................................................278
OVERHAUL.................................................................281
Components.............................................................281
Oil Channel ..............................................................284
Locations of Needle Bearings, Thrust Washers
and Snap Rings .......................................................285
DISASSEMBLY............................................................286
REPAIR FOR COMPONENT PARTS.........................297Oil Pump ..................................................................297
Control Valve Assembly ...........................................301
Control Valve Upper Body .......................................307
Control Valve Lower Body .......................................312
Reverse Clutch ........................................................314
High Clutch ..............................................................317
Forward and Overrun Clutches ...............................320
Low & Reverse Brake..............................................324
Forward Clutch Drum Assembly ..............................328
Rear Internal Gear and Forward Clutch Hub ..........330
Band Servo Piston Assembly ..................................333
Parking Pawl Components ......................................337
ASSEMBLY..................................................................339
Assembly (1) ............................................................339
Adjustment ...............................................................347
Assembly (2) ............................................................349
SERVICE DATA AND SPECIFICATIONS (SDS).......356
General Specifications .............................................356
Shift Schedule..........................................................356
Stall Revolution ........................................................356
Line Pressure...........................................................356
Return Springs .........................................................357
Accumulator O-ring ..................................................358
Clutches and Brakes ...............................................358
Oil Pump and Low One-way Clutch ........................360
Total End Play..........................................................360
Reverse Clutch Drum End Play ..............................361
Removal and Installation .........................................361
Shift Solenoid Valves ...............................................361
Solenoid Valves .......................................................361
A/T Fluid Temperature Sensor.................................361
Turbine Revolution Sensor ......................................361
Revolution Sensor ...................................................362
Dropping Resistor ....................................................362GI
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CONTENTS(Cont'd)
AT-3

Precautions for Supplemental Restraint System
(SRS) ªAIR BAGº and ªSEAT BELT
PRE-TENSIONERº
NBAT0001The 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 A/T and Engine
NBAT0002The 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 ªOFFº 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 an open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
IBe sure to route and secure the harnesses properly after work. Interference of the harness with a
bracket, etc. may cause the MIL to light up due to a 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 a malfunction of the EGR system or fuel injection system,
etc.
IBe sure to erase the unnecessary malfunction information (repairs completed) from the TCM and
ECM before returning the vehicle to the customer.
SEF289H
PrecautionsNBAT0003IBefore connecting or disconnecting the TCM harness
connector, turn ignition switch ªOFFº and disconnect
negative battery terminal. Failure to do so may damage
the TCM. Because battery voltage is applied to TCM even
if ignition switch is turned ªOFFº.
PRECAUTIONS
Precautions for Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
AT-6

IBefore assembly, apply a coat of recommended ATF to all
parts. Apply petroleum jelly to protect O-rings and seals, or
hold bearings and washers in place during assembly. Do not
use grease.
IExtreme care should be taken to avoid damage to O-rings,
seals and gaskets when assembling.
IReplace ATF cooler if excessive foreign material is found in oil
pan or clogging strainer. Refer to ªATF COOLER SERVICEº,
AT-9.
IAfter overhaul, refill the transmission with new ATF.
IWhen the A/T drain plug is removed, only some of the fluid is
drained. Old A/T fluid will remain in torque converter and ATF
cooling system.
Always follow the procedures when changing A/T fluid. Refer
to MA-21, ªChanging A/T Fluidº.
Service Notice or PrecautionsNBAT0004FAIL-SAFENBAT0004S01The TCM has an electronic Fail-Safe (limp home mode). This allows the vehicle to be driven even if a major
electrical input/output device circuit is damaged.
Under Fail-Safe, the vehicle always runs in third gear, even with a shift lever position of ª1º, ª2º or ªDº. The
customer may complain of sluggish or poor acceleration.
When the ignition key is turned ªONº following Fail-Safe operation, O/D OFF indicator lamp blinks for about
8 seconds. (For ªTCM SELF-DIAGNOSTIC PROCEDURE (No Tools)º, refer to AT-46.)
Fail-Safe may occur without electrical circuit damage if the vehicle is driven under extreme conditions (such
as excessive wheel spin followed by sudden braking). To recover normal shift pattern, turn the ignition key
ªOFFº for 5 seconds, then ªONº.
The blinking of the O/D OFF indicator lamp for about 8 seconds will appear only once and be cleared. The
customer may resume normal driving conditions.
Always follow the ªWORK FLOWº (Refer to AT-57).
The SELF-DIAGNOSIS results will be as follows:
The first SELF-DIAGNOSIS will indicate damage to the vehicle speed sensor or the revolution sensor.
During the next SELF-DIAGNOSIS, performed after checking the sensor, no damages will be indicated.
TORQUE CONVERTER SERVICENBAT0004S04The torque converter should be replaced under any of the following conditions:
IExternal leaks in the hub weld area.
IConverter hub is scored or damaged.
IConverter pilot is broken, damaged or fits poorly into crankshaft.
ISteel particles are found after flushing the cooler and cooler lines.
IPump is damaged or steel particles are found in the converter.
IVehicle has TCC shudder and/or no TCC apply. Replace only after all hydraulic and electrical diagnoses
have been made. (Converter clutch material may be glazed.)
IConverter is contaminated with engine coolant containing antifreeze.
IInternal failure of stator roller clutch.
IHeavy clutch debris due to overheating (blue converter).
ISteel particles or clutch lining material found in fluid filter or on magnet when no internal parts in unit are
worn or damaged Ð indicates that lining material came from converter.
The torque converter should not be replaced if:
IThe fluid has an odor, is discolored, and there is no evidence of metal or clutch facing particles.
PRECAUTIONS
Precautions (Cont'd)
AT-8

IThe threads in one or more of the converter bolt holes are damaged.
ITransmission failure did not display evidence of damaged or worn internal parts, steel particles or clutch
plate lining material in unit and inside the fluid filter.
IVehicle has been exposed to high mileage (only). The exception may be where the torque converter clutch
dampener plate lining has seen excess wear by vehicles operated in heavy and/or constant traffic, such
as taxi, delivery or police use.
ATF COOLER SERVICENBAT0004S02Replace ATF cooler if excessive foreign material is found in oil pan or clogging strainer.
Replace radiator lower tank (which includes ATF cooler) with a new one and flush cooler line using cleaning
solvent and compressed air. Refer to LC-19, ªREMOVAL AND INSTALLATIONº.
OBD-II SELF-DIAGNOSISNBAT0004S03IA/T self-diagnosis is performed by the TCM in combination with the ECM. The results can be read through
the blinking pattern of the O/D OFF indicator or the malfunction indicator lamp (MIL). Refer to the table on
AT-38 for the indicator used to display each self-diagnostic result.
IThe self-diagnostic results indicated by the MIL are automatically stored in both the ECM and TCM
memories.
Always perform the procedure ªHOW TO ERASE DTCº on AT-35 to complete the repair and avoid
unnecessary blinking of the MIL.
IThe following self-diagnostic items can be detected using ECM self-diagnostic results mode* only when
the O/D OFF indicator lamp does not indicate any malfunctions.
þ PNP switch
þ A/T 1st, 2nd, 3rd, or 4th gear function
þ A/T TCC S/V function (lock-up)
*: For details of OBD-II, refer to EC-59, ªIntroductionº.
ICertain systems and components, especially those related to OBD, may use the new style slide-
locking type harness connector. For description and how to disconnect, refer to EL-5, ªDescrip-
tionº.
Wiring Diagrams and Trouble DiagnosisNBAT0005When 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.
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PRECAUTIONS
Service Notice or Precautions (Cont'd)
AT-9

Tool number
(Kent-Moore No.)
Tool nameDescription
ST33200000
(J26082)
Drift
NT091
Installing oil pump housing oil seal Installing rear
oil seal
a: 60 mm (2.36 in) dia.
b: 44.5 mm (1.752 in) dia.
(J34291)
Shim setting gauge set
NT101
Selecting oil pump cover bearing race and oil
pump thrust washer
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PREPARATION
Special Service Tools (Cont'd)
AT-11

A/T Electrical Parts LocationNBAT0007
SAT124K
OVERALL SYSTEM
A/T Electrical Parts Location
AT-12