Infiniti QX4 (R50). Manual — part 1

AUTOMATIC TRANSMISSION

SECTION

AT

CONTENTS

TROUBLE DIAGNOSIS - INDEX . . . . . . . . . 4

Alphabetical & P No. Index for DTC . . . . . . ...4

PRECAUTIONS . . . . . . . . . . . . . . . ...6

Precautions for Supplemental Restraint System
(SRS)

″

AIR BAG

″

and

″

SEAT BELT

PRE-TENSIONER

″

. . . . . . . . . . . . . ..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. . . . . . . . . . . . . . . . ...63

TROUBLE 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) . 190

Description . . . . . . . . . . . . . . . ...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 In

″

P

″

and

″

N

″

Position . . . . . . . . . . . . . . . . . 221
3. In

″

P

″

Position, Vehicle Moves Forward Or

Backward When Pushed . . . . . . . . . . .222
4. In

″

N

″

Position, Vehicle Moves . . . . . . ...223

5. Large Shock.

″

N

″

->

″

R

″

Position . . . . . ...225

6. Vehicle Does Not Creep Backward In

″

R

″

Position . . . . . . . . . . . . . . . . . 227
7. Vehicle Does Not Creep Forward In

″

D

″

,

″

2

″

Or

″

1

″

Position. . . . . . . . . . . . . . .230

8. Vehicle Cannot Be Started From D

1

. . . . ...233

9. A/T Does Not Shift: D

1

-> D

2

Or Does Not

Kickdown: D

4

-> D

2

. . . . . . . . . . . . ..236

10. A/T Does Not Shift: D

2

-> D

3

. . . . . . . .239

11. A/T Does Not Shift: D

3

-> D

4

. . . . . . . .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

-> D

3

). . . . . . . . . . . . . .250

16. Vehicle Does Not Start From D

1

. . . . . ...252

17. A/T Does Not Shift: D

4

-> D

3

, When

Overdrive Control Switch

″

ON

″

->

″

OFF

″

. . . ...253

18. A/T Does Not Shift: D

3

-> 2

2

, When Selector

Lever

″

D

″

->

″

2

″

Position. . . . . . . . . . .254

CONTENTS

(Cont’d)

AT-2

19. A/T Does Not Shift: 2

2

-> 1

1

, When Selector

Lever

″

2

″

->

″

1

″

Position . . . . . . . . . . .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 . . . . . . .297

Oil 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 . . . . . . . . . . . . . 362

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CONTENTS

(Cont’d)

AT-3

Alphabetical & P No. Index for DTC

NBAT0179

ALPHABETICAL INDEX FOR DTC

NBAT0179S01

Items

(CONSULT-II screen terms)

DTC

Reference page

CONSULT-II

GST*1

A/T 1ST GR FNCTN

P0731

AT-120

A/T 2ND GR FNCTN

P0732

AT-126

A/T 3RD GR FNCTN

P0733

AT-132

A/T 4TH GR FNCTN

P0734

AT-138

A/T TCC S/V FNCTN

P0744

AT-153

ATF TEMP SEN/CIRC

P0710

AT-105

ENGINE SPEED SIG

P0725

AT-116

L/PRESS SOL/CIRC

P0745

AT-162

O/R CLTCH SOL/CIRC

P1760

AT-185

PNP SW/CIRC

P0705

AT-99

SFT SOL A/CIRC*2

P0750

AT-168

SFT SOL B/CIRC*2

P0755

AT-172

TCC SOLENOID/CIRC

P0740

AT-148

TP SEN/CIRC A/T*2

P1705

AT-176

VEH SPD SEN/CIR AT*3

P0720

AT-111

*1: These numbers are prescribed by SAE J2012.
*2: When the fail-safe operation occurs, the MIL illuminates.
*3: The MIL illuminates when both the “Revolution sensor signal” and the “Vehicle speed sensor signal” meet the fail-safe condition at
the same time.

TROUBLE DIAGNOSIS — INDEX

Alphabetical & P No. Index for DTC

AT-4