2001 INFINITI QX4 diagram

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
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX

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
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
CONTENTS(Cont'd)
AT-3

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.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
PRECAUTIONS
Service Notice or Precautions (Cont'd)
AT-9

Circuit DiagramNBAT0008
MAT906A
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
OVERALL SYSTEM
Circuit Diagram
AT-13

SAT964I
Malfunction Indicator Lamp (MIL)=NBAT0183The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned ON
without the engine running. This is a bulb check.
IIf the MIL does not light up, refer to EL-114, ªSchematicº.
(Or refer to EC-648, ªWiring Diagramº.)
2. When the engine is started, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction. For detail, refer to
EC-59, ªIntroductionº.
CONSULT-IINBAT0184After performing ªSELF-DIAGNOSTIC PROCEDURE (WITH CON-
SULT-II)º (AT-37), place check marks for results on the ªDIAGNOS-
TIC WORKSHEETº, AT-55. Reference pages are provided follow-
ing the items.
NOTICE:
1) The CONSULT-II electrically displays shift timing and lock-up
timing (that is, operation timing of each solenoid).
Check for time difference between actual shift timing and the
CONSULT-II display. If the difference is noticeable, mechani-
cal parts (except solenoids, sensors, etc.) may be malfunction-
ing. Check mechanical parts using applicable diagnostic pro-
cedures.
2) Shift schedule (which implies gear position) displayed on
CONSULT-II and that indicated in Service Manual may differ
slightly. This occurs because of the following reasons:
IActual shift schedule has more or less tolerance or allowance,
IShift schedule indicated in Service Manual refers to the point
where shifts start, and
IGear position displayed on CONSULT-II indicates the point
where shifts are completed.
3) Shift solenoid valve ªAº or ªBº is displayed on CONSULT-II at
the start of shifting. Gear position is displayed upon completion
of shifting (which is computed by TCM).
4) Additional CONSULT-II information can be found in the Opera-
tion Manual supplied with the CONSULT-II unit.
SAT014K
SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)NBAT0184S011. Turn on CONSULT-II and touch ªENGINEº for OBD-II detected
items or touch ªA/Tº for TCM self-diagnosis.
If A/T is not displayed, check TCM power supply and ground
circuit. Refer to AT-92. If result is NG, refer to EL-9, ªSche-
maticº.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Malfunction Indicator Lamp (MIL)
AT-37

Wiring Diagram Ð AT Ð MAINNBAT0185
MAT907A
TROUBLE DIAGNOSIS FOR POWER SUPPLY
Wiring Diagram Ð AT Ð MAIN
AT-96

TCM TERMINALS AND REFERENCE VALUENBAT0185S01Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
(Approx.)
10 W/R Power source
When turning ignition switch to ªONº.Battery volt-
age
When turning ignition switch to ªOFFº. 0V
19 W/R Power source Same as No. 10
25 B Ground
Ð0V
28 R/YPower source
(Memory back-up)
or
When turning ignition switch to ªOFFº.Battery volt-
age
When turning ignition switch to ªONº.Battery volt-
age
48 B Ground
Ð0V
Diagnostic ProcedureNBAT0223
1 CHECK TCM POWER SOURCE STEP 1
1. Turn ignition switch to ON position.
(Do not start engine.)
2. Check voltage between TCM terminals 10, 19, 28 and ground.
SAT611J
OK or NG
OK©GO TO 2.
NG©GO TO 3.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
TROUBLE DIAGNOSIS FOR POWER SUPPLY
Wiring Diagram Ð AT Ð MAIN (Cont'd)
AT-97