2008 INFINITI QX56 diagram

HEATED STEERING WHEELST-7
< FUNCTION DIAGNOSIS >
C
DE
F
H I
J
K L
M A
B
ST
N
O P
FUNCTION DIAGNOSIS
HEATED STEERING WHEEL
System DiagramINFOID:0000000001696234
System DescriptionINFOID:0000000001696235
The heated steering wheel switch controls the heated steeri ng relay. When the switch is turned on, the relay is
energized and the heated steering system will operate. T he heated steering system will turn off when the
steering wheel temperature reaches approximately 30 ° C (86 ° F). Heated steering system operation can also
be canceled by pressing the heated steering wheel switch again.
NOTE:
If the surface temperature of the steering wheel is below 68 ° F (20 ° C), the system will heat the steering wheel,
and cycle off and on to maintain a temperature above 68 ° F (20 ° C). The indicator light will remain on as long
as the system is on. Push the switch again to turn the heated steering wheel system off manually. The indica-
tor light will go off.
Component Parts LocationINFOID:0000000001696236
AWGIA0022GB
1. Heated steering relay M71 2. Combination switch (spiral cable) M52 3. Heated steering wheel M114
4. Heated steering wheel switch M260
ALGIA0030ZZ
Revision: March 2010 2008 QX56

HEATED STEERING WHEELST-9
< COMPONENT DIAGNOSIS >
C
DE
F
H I
J
K L
M A
B
ST
N
O P
COMPONENT DIAGNOSIS
HEATED STEERING WHEEL
Wiring DiagramINFOID:0000000001696238
ALGWA0007GB
Revision: March 2010 2008 QX56

STR-1
ENGINE
C
DE
F
G H
I
J
K L
M
SECTION STR
A
STR
N
O P
CONTENTS
STARTING SYSTEM
PRECAUTION ....... ........................................2
PRECAUTIONS .............................................. .....2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
2
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
2
Precaution for Power Generation Variable Voltage
Control System ..........................................................
3
PREPARATION ............................................4
PREPARATION .............................................. .....4
Special Service Tool ........................................... ......4
Commercial Service Tool ..........................................4
BASIC INSPECTION ....................................5
DIAGNOSIS AND REPAIR WORKFLOW ..... .....5
Work Flow ........................................................... ......5
FUNCTION DIAGNOSIS ...............................8
STARTING SYSTEM ...................................... .....8
System Diagram .................................................. ......8
System Description ...................................................8
Component Parts Location ........................................8
Component Description ............................................9
COMPONENT DIAGNOSIS .........................10
B TERMINAL CIRCUIT .....................................10
Description ........................................................... ....10
Diagnosis Procedure ...............................................10
S CONNECTOR CIRCUIT .................................11
Description ...............................................................11
Diagnosis Procedure ...............................................11
STARTING SYSTEM .........................................12
Wiring Diagram .................................................... ....12
SYMPTOM DIAGNOSIS ..............................16
STARTING SYSTEM .........................................16
Symptom Table ................................................... ....16
ON-VEHICLE REPAIR .................................17
STARTER MOTOR ...........................................17
Removal and Installation ..................................... ....17
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... .......................................... ...
18
STARTER MOTOR ...........................................18
Starter .................................................................. ....18
Revision: March 2010 2008 QX56

STR-8
< FUNCTION DIAGNOSIS >
STARTING SYSTEM
FUNCTION DIAGNOSIS
STARTING SYSTEM
System DiagramINFOID:0000000001696224
System DescriptionINFOID:0000000001696225
The starter motor plunger closes and provides a closed circuit between the battery and the starter motor. The
starter motor is grounded to the cylinder block. With power and ground supplied, the starter motor operates.
Component Parts LocationINFOID:0000000001696226
ALBIA0416GB
1. A/T assembly F9 (with built in TCM
F502) 2. IPDM E/R E119, E120, E122, E124 3. BCM M18 (view with instrument panel
lower LH panel removed)
AWBIA0127ZZ
Revision: March 2010 2008 QX56

STR-12
< COMPONENT DIAGNOSIS >
STARTING SYSTEM
STARTING SYSTEM
Wiring DiagramINFOID:0000000001696232
AWBWA0140GB
Revision: March 20102008 QX56

TM-3
CEF
G H
I
J
K L
M A
B
TM
N
O P
P1752 INPUT CLUTCH SOLENOID .............. ....80
Description .......................................................... ....80
CONSULT-III Reference Value in Data Monitor
Mode ................................................................... ....
80
On Board Diagnosis Logic ......................................80
Possible Cause .......................................................80
DTC Confirmation Procedure ..................................80
Diagnosis Procedure ...............................................80
P1757 FRONT BRAKE SOLENOID ...................82
Description .......................................................... ....82
CONSULT-III Reference Value in Data Monitor
Mode ................................................................... ....
82
On Board Diagnosis Logic ......................................82
Possible Cause .......................................................82
DTC Confirmation Procedure ..................................82
Diagnosis Procedure ...............................................82
P1762 DIRECT CLUTCH SOLENOID ................84
Description .......................................................... ....84
CONSULT-III Reference Value in Data Monitor
Mode ................................................................... ....
84
On Board Diagnosis Logic ......................................84
Possible Cause .......................................................84
DTC Confirmation Procedure ..................................84
Diagnosis Procedure ...............................................84
P1767 HIGH AND LOW REVERSE CLUTCH
SOLENOID .........................................................
86
Description .......................................................... ....86
CONSULT-III Reference Value in Data Monitor
Mode ................................................................... ....
86
On Board Diagnosis Logic ......................................86
Possible Cause .......................................................86
DTC Confirmation Procedure ..................................86
Diagnosis Procedure ...............................................86
P1772 LOW COAST BRAKE SOLENOID .........88
Description .......................................................... ....88
CONSULT-III Reference Value in Data Monitor
Mode ................................................................... ....
88
On Board Diagnosis Logic ......................................88
Possible Cause .......................................................88
DTC Confirmation Procedure ..................................88
Diagnosis Procedure ...............................................88
P1774 LOW COAST BRAKE SOLENOID .........90
Description .......................................................... ....90
CONSULT-III Reference Value in Data Monitor
Mode ................................................................... ....
90
On Board Diagnosis Logic ......................................90
Possible Cause .......................................................90
DTC Confirmation Procedure ..................................90
Diagnosis Procedure ...............................................90
MAIN POWER SUPPLY AND GROUND CIR-
CUIT ....................................................................
92
Diagnosis Procedure ........................................... ....92
CLOSED THROTTLE POSITION AND WIDE
OPEN THROTTLE POSITION CIRCUIT ...........
94
CONSULT-III Reference Value in Data Monitor
Mode .................................................................... ....
94
Diagnosis Procedure ...............................................94
BRAKE SIGNAL CIRCUIT ................................95
CONSULT-III Reference Va lue in Data Monitor
Mode .................................................................... ....
95
Diagnosis Procedure ...............................................95
TOW MODE SWITCH .......................................96
Description ...............................................................96
Diagnosis Procedure ...............................................96
A/T SHIFT LOCK SYSTEM ...............................97
Wiring Diagram - A/T Shift Lock System .................97
Terminals And Reference Values ..........................100
Component Description ....................................... ..100
ECU DIAGNOSIS .......................................103
TCM .................................................................103
Reference Value .................................................. ..103
Wiring Diagram — A/T CONTROL SYSTEM — .. ..105
Fail-Safe .............................................................. ..114
DTC Inspection Priority Chart ................................116
DTC No. Index .......................................................116
DTC Alphabetical Index .........................................117
SYMPTOM DIAGNOSIS ............................118
SYSTEM SYMPTOM .......................................118
A/T Check Indicator Lamp Does Not Come On ... ..118
Engine Cannot Be Started in "P" or "N" Position ...118
In "P" Position, Vehicle Moves When Pushed .......119
In "N" Position, Vehicle Moves ..............................119
Large Shock("N" to "D" Position) ...........................121
Vehicle Does Not Creep Backward in "R" Position ..123
Vehicle Does Not Creep Forward in "D" Position ..125
Vehicle Cannot Be Started from D1 ......................128
A/T Does Not Shift: D1→D2 ..................................130
A/T Does Not Shift: D2→ D3 ..................................131
A/T Does Not Shift: D3→ D4 ..................................133
A/T Does Not Shift: D4→ D5 ..................................135
A/T Does Not Perform Lock-up ........................... ..137
A/T Does Not Hold Lock-up Condition ...................139
Lock-up Is Not Released .......................................140
Engine Speed Does Not Return to Idle .................141
A/T Does Not Shift: 5GR → 4GR ........................ ..142
A/T Does Not Shift: 4GR → 3GR ........................ ..144
A/T Does Not Shift: 3GR → 2GR ........................ ..146
A/T Does Not Shift: 2GR → 1GR ........................ ..147
Vehicle Does Not Decelerate By Engine Brake ... ..149
Symptom Table .....................................................151
PRECAUTION ............................................173
PRECAUTIONS ...............................................173
Revision: March 2010 2008 QX56

A/T CONTROL SYSTEMTM-21
< FUNCTION DIAGNOSIS >
CEF
G H
I
J
K L
M A
B
TM
N
O P
CONTROL SYSTEM DIAGRAM
CAN CommunicationINFOID:0000000001603991
SYSTEM DESCRIPTION
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only. For details, refer to LAN-4,
"System Description".
SENSORS (or SIGNALS)
⇒TCM
⇒ACTUATORS
Transmission range switch
Accelerator pedal position sensor
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Output speed sensor
Vehicle speed signal
Stop lamp switch signal
Input speed sensor
1st position switch signal
4th position switch signal
ATF pressure switch 2 signal
Tow mode switch signal Shift control
Line pressure control
Lock-up control
Engine brake control
Timing control
Fail-safe control
Self-diagnosis
CONSULT-III co
mmunication
line
Duet-EA control
CAN system Input clutch solenoid valve
Direct clutch solenoid valve
Front brake solenoid valve
High and low reverse clutch sole-
noid 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
JSDIA1315GB
Revision: March 2010
2008 QX56

TM-24
< FUNCTION DIAGNOSIS >
A/T CONTROL SYSTEM
The necessary and adequate line pressure for shift change is set.
For this reason, line pressure pattern setting corresponds to input
torque and gearshift selection. Also, line pressure characteristic is
set according to engine speed, during engine brake operation.
At Low Fluid Temperature
When the A/T fluid temperature drops below the prescribed tempera-
ture, in order to speed up the action of each friction element, the line
pressure is set higher than the normal line pressure characteristic.
Shift ControlINFOID:0000000001603994
The clutch pressure control solenoid is controlled by the signals from the switches and sensors. Thus, the
clutch pressure is adjusted to be appropriate to the engine load state and vehicle driving state. It becomes
possible to finely control the clutch hydraulic pressure with high precision and a smoother shift change charac-
teristic is attained.
SHIFT CHANGE
The clutch is controlled with the optimum timing and oil pressure by the engine speed, engine torque informa-
tion, etc.
Shift Change System Diagram
PCIA0010E
PCIA0011E
PCIA0012E
Revision: March 2010 2008 QX56