2006 INFINITI QX56 diagram

AT-2Revision: November 20092006 QX56
CONSULT-II Reference Value .............................
.105
On Board Diagnosis Logic ................................... .105
Possible Cause .................................................... .105
DTC Confirmation Procedure .............................. .105
Wiring Diagram — AT — PNP/SW ...................... .106
Diagnostic Procedure .......................................... .107
DTC P0717 TURBINE REVOLUTION SENSOR ... .109
Description ........................................................... .109
CONSULT-II Reference Value ............................. .109
On Board Diagnosis Logic ................................... .109
Possible Cause .................................................... .109
DTC Confirmation Procedure .............................. .109
Diagnostic Procedure .......................................... .110
DTC P0720 VEHICLE SPEED SENSOR A/T (REV-
OLUTION SENSOR) .............................................. . 111
Description ........................................................... ..111
CONSULT-II Reference Value ...............................111
On Board Diagnosis Logic ................................... ..111
Possible Cause ......................................................111
DTC Confirmation Procedure .............................. ..111
Wiring Diagram — AT — VSSA/T ........................ .113
Diagnostic Procedure .......................................... .114
DTC P0725 ENGINE SPEED SIGNAL .................. .116
Description ........................................................... .116
CONSULT-II Reference Value ............................. .116
On Board Diagnosis Logic ................................... .116
Possible Cause .................................................... .116
DTC Confirmation Procedure .............................. .116
Diagnostic Procedure .......................................... .116
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE ................................................ .118
Description ........................................................... .118
CONSULT-II Reference Value ............................. .118
On Board Diagnosis Logic ................................... .118
Possible Cause .................................................... .118
DTC Confirmation Procedure .............................. .118
Diagnostic Procedure .......................................... .119
DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP) .120
Description ........................................................... .120
CONSULT-II Reference Value ............................. .120
On Board Diagnosis Logic ................................... .120
Possible Cause .................................................... .120
DTC Confirmation Procedure .............................. .120
Diagnostic Procedure .......................................... .121
DTC P0745 LINE PRESSURE SOLENOID VALVE .122
Description ........................................................... .122
CONSULT-II Reference Value ............................. .122
On Board Diagnosis Logic ................................... .122
Possible Cause .................................................... .122
DTC Confirmation Procedure .............................. .122
Diagnostic Procedure .......................................... .123
DTC P1705 THROTTLE POSITION SENSOR ...... .124
Description ........................................................... .124
CONSULT-II Reference Value ............................. .124
On Board Diagnosis Logic ................................... .124
Possible Cause .................................................... .124
DTC Confirmation Procedure .............................. .124
Diagnostic Procedure .......................................... .124
DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT .................................................................
.127
Description ........................................................... .127
CONSULT-II Reference Value .............................. .127
On Board Diagnosis Logic ................................... .127
Possible Cause .................................................... .127
DTC Confirmation Procedure ............................... .127
Wiring Diagram — AT — FTS .............................. .128
Diagnostic Procedure ........................................... .129
Component Inspection ......................................... .130
DTC P1721 VEHICLE SPEED SENSOR MTR ...... .132
Description ........................................................... .132
CONSULT-II Reference Value .............................. .132
On Board Diagnosis Logic ................................... .132
Possible Cause .................................................... .132
DTC Confirmation Procedure ............................... .132
Diagnostic Procedure ........................................... .133
DTC P1730 A/T INTERLOCK ................................ .134
Description ........................................................... .134
On Board Diagnosis Logic ................................... .134
Possible Cause .................................................... .134
DTC Confirmation Procedure ............................... .134
Judgement of A/T Interlock .................................. .135
Diagnostic Procedure ........................................... .135
DTC P1731 A/T 1ST ENGINE BRAKING .............. .137
Description ........................................................... .137
CONSULT-II Reference Value .............................. .137
On Board Diagnosis Logic ................................... .137
Possible Cause .................................................... .137
DTC Confirmation Procedure ............................... .137
Diagnostic Procedure ........................................... .138
DTC P1752 INPUT CLUTCH SOLENOID VALVE . .139
Description ........................................................... .139
CONSULT-II Reference Value .............................. .139
On Board Diagnosis Logic ................................... .139
Possible Cause .................................................... .139
DTC Confirmation Procedure ............................... .139
Diagnostic Procedure ........................................... .140
DTC P1754 INPUT CLUTCH SOLENOID VALVE
FUNCTION ............................................................. .141
Description ........................................................... .141
CONSULT-II Reference Value .............................. .141
On Board Diagnosis Logic ................................... .141
Possible Cause .................................................... .141
DTC Confirmation Procedure ............................... .141
Diagnostic Procedure ........................................... .142
DTC P1757 FRONT BRAKE SOLENOID VALVE .. .143
Description ........................................................... .143
CONSULT-II Reference Value .............................. .143
On Board Diagnosis Logic ................................... .143
Possible Cause .................................................... .143
DTC Confirmation Procedure ............................... .143
Diagnostic Procedure ........................................... .144
DTC P1759 FRONT BRAKE SOLENOID VALVE
FUNCTION ............................................................. .145
Description ........................................................... .145
CONSULT-II Reference Value .............................. .145
On Board Diagnosis Logic ................................... .145
Possible Cause .................................................... .145

AT-3
DE
F
G H
I
J
K L
M A
B
AT
Revision: November 2009 2006 QX56
DTC Confirmation Procedure ..............................
. 145
Diagnostic Procedure .......................................... . 146
DTC P1762 DIRECT CLUTCH SOLENOID VALVE . 147
Description .......................................................... . 147
CONSULT-II Reference Value ............................. . 147
On Board Diagnosis Logic .................................. . 147
Possible Cause ................................................... . 147
DTC Confirmation Procedure .............................. . 147
Diagnostic Procedure .......................................... . 148
DTC P1764 DIRECT CLUTCH SOLENOID VALVE
FUNCTION ............................................................. . 149
Description .......................................................... . 149
CONSULT-II Reference Value ............................. . 149
On Board Diagnosis Logic .................................. . 149
Possible Cause ................................................... . 149
DTC Confirmation Procedure .............................. . 149
Diagnostic Procedure .......................................... . 150
DTC P1767 HIGH AND LOW REVERSE CLUTCH
SOLENOID VALVE ................................................ . 151
Description .......................................................... . 151
CONSULT-II Reference Value ............................. . 151
On Board Diagnosis Logic .................................. . 151
Possible Cause ................................................... . 151
DTC Confirmation Procedure .............................. . 151
Diagnostic Procedure .......................................... . 152
DTC P1769 HIGH AND LOW REVERSE CLUTCH
SOLENOID VALVE FUNCTION ............................ . 153
Description .......................................................... . 153
CONSULT-II Reference Value ............................. . 153
On Board Diagnosis Logic .................................. . 153
Possible Cause ................................................... . 153
DTC Confirmation Procedure .............................. . 153
Diagnostic Procedure .......................................... . 154
DTC P1772 LOW COAST BRAKE SOLENOID
VALVE .................................................................... . 155
Description .......................................................... . 155
CONSULT-II Reference Value ............................. . 155
On Board Diagnosis Logic .................................. . 155
Possible Cause ................................................... . 155
DTC Confirmation Procedure .............................. . 155
Diagnostic Procedure .......................................... . 156
DTC P1774 LOW COAST BRAKE SOLENOID
VALVE FUNCTION ................................................ . 157
Description .......................................................... . 157
CONSULT-II Reference Value ............................. . 157
On Board Diagnosis Logic .................................. . 157
Possible Cause ................................................... . 157
DTC Confirmation Procedure .............................. . 157
Diagnostic Procedure .......................................... . 158
DTC P1841 ATF PRESSURE SWITCH 1 .............. . 159
Description .......................................................... . 159
CONSULT-II Reference Value ............................. . 159
On Board Diagnosis Logic .................................. . 159
Possible Cause ................................................... . 159
DTC Confirmation Procedure .............................. . 159
Diagnostic Procedure .......................................... . 160
DTC P1843 ATF PRESSURE SWITCH 3 .............. . 161
Description .......................................................... . 161
CONSULT-II Reference Value ............................. . 161On Board Diagnosis Logic ...................................
.161
Possible Cause .................................................... .161
DTC Confirmation Procedure .............................. .161
Diagnostic Procedure .......................................... .162
DTC P1845 ATF PRESSURE SWITCH 5 .............. .163
Description ........................................................... .163
CONSULT-II Reference Value ............................. .163
On Board Diagnosis Logic ................................... .163
Possible Cause .................................................... .163
DTC Confirmation Procedure .............................. .163
Diagnostic Procedure .......................................... .164
DTC P1846 ATF PRESSURE SWITCH 6 .............. .165
Description ........................................................... .165
CONSULT-II Reference Value ............................. .165
On Board Diagnosis Logic ................................... .165
Possible Cause .................................................... .165
DTC Confirmation Procedure .............................. .165
Diagnostic Procedure .......................................... .166
MAIN POWER SUPPLY AND GROUND CIRCUIT .167
Wiring Diagram — AT — MAIN ........................... .167
Diagnostic Procedure .......................................... .168
CLOSED THROTTLE POSITION AND WIDE OPEN
THROTTLE POSITION CIRCUIT ........................... .171
CONSULT-II Reference Value ............................. .171
Diagnostic Procedure .......................................... .171
BRAKE SIGNAL CIRCUIT ..................................... .172
CONSULT-II Reference Value ............................. .172
Diagnostic Procedure .......................................... .172
TOW MODE SWITCH ............................................ .173
Description ........................................................... .173
Wiring Diagram — AT — TMSW ......................... .174
Diagnostic Procedure .......................................... .175
TROUBLE DIAGNOSIS FOR SYMPTOMS ........... .176
Wiring Diagram — AT — NONDTC ..................... .176
A/T CHECK Indicator Lamp Does Not Come On . 179
Engine Cannot Be Started In “P” or “N” Position . .179
In “P” Position, Vehicle Moves When Pushed ..... .180
In “N” Position, Vehicle Moves ............................. .181
Large Shock (“N” to “D” Position) ........................ .182
Vehicle Does Not Creep Backward In “R” Position .186
Vehicle Does Not Creep Forward In “D” Position . 189
Vehicle Cannot Be Started From D
1 .................... .191
A/T Does Not Shift: D
1 → D2 ............................... .194
A/T Does Not Shift: D
2 → D3 ............................... .196
A/T Does Not Shift: D
3 → D4 ............................... .198
A/T Does Not Shift: D
4 → D5 ............................... .201
A/T Does Not Perform Lock-up ........................... .203
A/T Does Not Hold Lock-up Condition ................. .205
Lock-up Is Not Released ..................................... .207
Engine Speed Does Not Return to Idle ............... .208
A/T Does Not Shift: 5th gear → 4th gear ............. .209
A/T Does Not Shift: 4th gear → 3rd gear ............. .212
A/T Does Not Shift: 3rd gear → 2nd gear ............ .213
A/T Does Not Shift: 2nd gear → 1st gear .............215
Vehicle Does Not Decelerate By Engine Brake ... .218
A/T SHIFT LOCK SYSTEM ................................... .221
Description ........................................................... .221
Shift Lock System Electrical Parts Location ........ .221
Wiring Diagram — A/T — SHIFT ......................... .222

AT-30
A/T CONTROL SYSTEM
Revision: November 20092006 QX56
TCM FunctionECS00CDW
The function of the TCM is to:

Receive input signals sent from various switches and sensors.

Determine required line pressure, shifting point, lock-up operation, and engine brake operation.

Send required output signals to the respective solenoids.
CONTROL SYSTEM OUTLINE
The automatic transmission senses vehicle operating conditions through various sensors or signals. It always
controls the optimum shift position and reduces shifting and lock-up shocks.
CONTROL SYSTEM DIAGRAM
SENSORS (or SIGNALS)

TCM

ACTUATORS
PNP switch
Accelerator pedal position sensor
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Revolution sensor
Vehicle speed signal
Stop lamp switch signal
Turbine revolution sensor
1st position switch signal
4th position switch signal
ATF pressure switch signal
Tow mode switch signal Shift control
Line pressure control
Lock-up control
Engine brake control
Timing control
Fail-safe control
Self-diagnosis
CONSULT-II communication line
Duet-EA control
CAN system
Input clutch solenoid valve
Direct clutch solenoid valve
Front brake solenoid valve
High and low reverse clutch
solenoid valve
Low coast brake solenoid valve
Torque converter clutch solenoid
valve
Line pressure solenoid valve
A/T CHECK indicator lamp
Starter relay
Back-up lamp relay
SCIA5624E

AT-34
A/T CONTROL SYSTEM
Revision: November 20092006 QX56
Shift Change System Diagram
*1: Full phase real-time feedback control monitors movement of gear ratio at gear change, and controls oil
pressure at real-time to achieve the best gear ratio.
Lock-up ControlECS00CE1
The torque converter clutch piston in the torque converter is engaged to eliminate torque converter slip to
increase power transmission efficiency.
The torque converter clutch control valve operation is controlled by the torque converter clutch solenoid valve,
which is controlled by a signal from TCM, and the torque converter clutch control valve engages or releases
the torque converter clutch piston.
Lock-up Operation Condition Table
TORQUE CONVERTER CLUTCH CONTROL VALVE CONTROL
Lock-up Control System Diagram
Lock-up Released

In the lock-up released state, the torque converter clutch control valve is set into the unlocked state by the
torque converter clutch solenoid and the lock-up apply pressure is drained.
In this way, the torque converter clutch piston is not coupled.
PCIA0013E
Select leverD position4 position 3 position 2 position
G ea r p osit io n 54432
Lock-up ×–×××
Slip lock-up ××–––
PCIA0014E

AT-50
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Circuit DiagramECS00CED
BCWA0496E

DTC U1000 CAN COMMUNICATION LINEAT-97
DE
F
G H
I
J
K L
M A
B
AT
Revision: November 2009 2006 QX56
Wiring Diagram — AT — CANECS00CEU
BCWA0320E

DTC P0615 START SIGNAL CIRCUITAT-101
DE
F
G H
I
J
K L
M A
B
AT
Revision: November 2009 2006 QX56
Wiring Diagram — AT — STSIGECS00CF1
BCWA0321E

AT-106
DTC P0705 PARK/NEUTRAL POSITION SWITCH
Revision: November 20092006 QX56
Wiring Diagram — AT — PNP/SWECS00CF8
BCWA0520E