diagram INFINITI QX56 2011 Factory Service Manual

HEATED STEERING WHEEL SWITCH INDICATOR LAMP DOES NOT TURN ON
ST-27
< SYMPTOM DIAGNOSIS >
C
D E
F
H I
J
K L
M A
B
ST
N
O P
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace damaged parts.
4.CHECK HEATED STEERING WHEEL RELAY
Check heated steering wheel relay. Refer to ST-22, "
Component Inspection (Heated Steering Wheel Relay)".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Replace heated steering wheel relay. Refer to ST-7, "
Component Parts Location (Heated Steering
Wheel)".
5.CHECK HARNESS BETWEEN HEATED STEERING WHEEL RELAY AND HEATED STEERING WHEEL
SWITCH
1. Check continuity between heated steering wheel relay harness connector terminal and heated steering
wheel switch harness connector terminal.
2. Check continuity between heated steering w heel relay harness connector terminal and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair or replace damaged parts.
6.CHECK HARNESS BETWEEN FUSE BLOCK (J/B) AND HEATED STEERING WHEEL SWITCH
1. Check continuity between fuse block (J/B) connec tor terminal and heated steering wheel switch harness
connector terminal.
2. Check continuity between fuse block (J/B) harness connector terminal and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair or replace damaged parts.
7.DETECT MALFUNCTIONING ITEM
Check the following.
 Ignition switch
 Harness for short or open between ignition s witch and fuse block (J/B). Refer to PG-11, "
Wiring Diagram -
BATTERY POWER SUPPLY -".
 10A fuse [No.3, located in the fuse block (J/B)]. Refer to PG-143, "
Fuse, Connector and Terminal Arrange-
ment".
 Fuse block (J/B)
Is the inspection result normal?
YES >> Replace heated steering wheel switch. Refer to ST-56, "Removal and Installation".
Heated steering wheel relay Heated steering wheel switch
Continuity
Connector Terminal Connector Terminal
E90 2 M52 2 Existed
Heated steering wheel relay GroundContinuity
Connector Terminal
E90 2 Not existed
Fuse block (J/B) Heated steering wheel switch Continuity
Connector Terminal Connector Terminal
M1 2A M52 1 Existed
Fuse block (J/B) GroundContinuity
Connector Terminal
M1 2A Not existed
Revision: 2010 May2011 QX56

STC-1
STEERING
C
DE
F
H I
J
K L
M
SECTION STC
A
B
STC
N
O P
CONTENTS
STEERING CONTROL 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
SYSTEM DESCRIPTION ..............................4
COMPONENT PARTS ................................... .....4
Component Parts Location .................................. ......4
Component Description .............................................4
Power Steering Control Unit ......................................4
Power Steering Solenoid Valve .................................4
SYSTEM ..............................................................5
EPS SYSTEM ........................................ ......................5
EPS SYSTEM : System De scription .........................5
EPS SYSTEM : Fail-Safe ..........................................6
ECU DIAGNOSIS INFO RMATION ...............8
POWER STEERING CONTROL UNIT ........... .....8
Reference Value ................................................. ......8
Fail-Safe ....................................................................9
WIRING DIAGRAM ......................................10
ELECTRONICALLY CONTROLLED POWER
STEERING SYSTEM ...................................... ....
10
Wiring Diagram ................................................... ....10
BASIC INSPECTION ...................................13
DIAGNOSIS AND REPAIR WORK FLOW .......13
Work Flow ............................................................ ....13
DTC/CIRCUIT DIAGNOSIS .........................14
POWER SUPPLY AND GROUND CIRCUIT ....14
Diagnosis Procedure ........................................... ....14
POWER STEERING SOLENOID VALVE .........16
Component Function Check ....................................16
Diagnosis Procedure ...............................................16
Component Inspection .............................................17
ENGINE SPEED SIGNAL CIRCUIT ..................18
Diagnosis Procedure ........................................... ....18
VEHICLE SPEED SIGNAL CIRCUIT ................20
Diagnosis Procedure ...............................................20
SYMPTOM DIAGNOSIS ..............................22
UNBALANCE STEERING WHEEL TURNING
FORCE (TORQUE VARIATION) .......................
22
Description ........................................................... ....22
Diagnosis Procedure ...............................................22
REMOVAL AND INSTALLATION ...............23
POWER STEERING CONTROL UNIT ..............23
Removal and Installation ..................................... ....23
Revision: 2010 May2011 QX56

SYSTEMSTC-5
< SYSTEM DESCRIPTION >
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DE
F
H I
J
K L
M A
B
STC
N
O P
SYSTEM
EPS SYSTEM
EPS SYSTEM : System DescriptionINFOID:0000000006256119
 The EPS system controls the power steering sol enoid valve through the power steering control unit.
 The valve driving voltage to control the power steering solenoid
valve varies according to the vehicle speed.
CONTROL DIAGRAM
CROSS-SECTIONAL VIEW
JPGIB0021GB
JPGIB0017GB
SGIA1389E
Revision: 2010 May2011 QX56

STC-10
< WIRING DIAGRAM >
ELECTRONICALLY CONTROLLED POWER STEERING SYSTEM
WIRING DIAGRAM
ELECTRONICALLY CONTROLLED POWER STEERING SYSTEM
Wiring Diagram INFOID:0000000006256123
JCGWM0392GB
Revision: 2010 May2011 QX56

ELECTRONICALLY CONTROLLED POWER STEERING SYSTEMSTC-11
< WIRING DIAGRAM >
C
DE
F
H I
J
K L
M A
B
STC
N
O P
JCGWM0393GB
Revision: 2010 May2011 QX56

STC-12
< WIRING DIAGRAM >
ELECTRONICALLY CONTROLLED POWER STEERING SYSTEM
JCGWM0394GB
Revision: 2010 May2011 QX56

STC-14
< DTC/CIRCUIT DIAGNOSIS >
POWER SUPPLY AND GROUND CIRCUIT
DTC/CIRCUIT DIAGNOSIS
POWER SUPPLY AND GROUND CIRCUIT
Diagnosis ProcedureINFOID:0000000006256125
1.CHECK POWER SUPPLY (1)
1. Turn the ignition switch OFF.
2. Disconnect power steering control unit harness connector.
3. Check the voltage between power steering control unit harness connector and ground.
4. Turn the ignition switch ON. CAUTION:
Never start the engine.
5. Check the voltage between power steering control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK POWER SUPPLY (2)
1. Turn the ignition switch OFF.
2. Check 10A fuse (#3).
3. Disconnect fuse block (J/B) harness connector.
4. Check the continuity between power steering cont rol unit harness connector and fuse block (J/B) harness
connector.
5. Check the continuity between power st eering control unit harness connector and ground.
Is the inspection result normal?
YES >> Perform trouble diagnosis for ignition power supply circuit. Refer to PG-89, "Wiring Diagram -
IGNITION POWER SUPPLY -".
NO >> Repair or replace damaged parts.
3.CHECK GROUND CIRCUIT
1. Turn the ignition switch OFF.
2. Check the continuity between power st eering control unit harness connector and ground.
Power steering control unit
—Voltage
Connector Terminal
M108 3 Ground 0 V
Power steering control unit — Voltage
Connector Terminal
M108 3 Ground Battery voltage
Power steering control unit Fuse block (J/B) Continuity
Connector Terminal Connector Terminal
M108 3 M1 2A Existed
Power steering control unit —Continuity
Connector Terminal
M108 3 Ground Not existed
Revision: 2010 May2011 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
PREPARATION ............................................4
PREPARATION .............................................. .....4
Special Service Tools .......................................... ......4
Commercial Service Tools ........................................4
SYSTEM DESCRIPTION ..............................5
COMPONENT PARTS ................................... .....5
Component Parts Location .................................. ......5
Component Description ............................................5
SYSTEM ..............................................................6
System Diagram .................................................. ......6
System Description ...................................................6
WIRING DIAGRAM .......................................7
STARTING SYSTEM ...................................... .....7
Wiring Diagram ................................................... ......7
BASIC INSPECTION ...................................11
DIAGNOSIS AND REPAIR WORKFLOW ........11
Work Flow ............................................................ ....11
DTC/CIRCUIT DIAGNOSIS .........................14
B TERMINAL CIRCUIT .....................................14
Diagnosis Procedure ........................................... ....14
S CONNECTOR CIRCUIT .................................15
Diagnosis Procedure ...............................................15
SYMPTOM DIAGNOSIS ..............................16
STARTING SYSTEM .........................................16
Symptom Table ................................................... ....16
REMOVAL AND INSTALLATION ...............17
STARTER MOTOR ...........................................17
Exploded View ..................................................... ....17
Removal and Installation .........................................18
Inspection ................................................................18
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... .............................................
20
SERVICE DATA AND SPECIFICATIONS
(SDS) .................................................................
20
Starter Motor .......................................................
Revision: 2010 May2011 QX56

STR-6
< SYSTEM DESCRIPTION >
SYSTEM
SYSTEM
System DiagramINFOID:0000000006275520
System DescriptionINFOID:0000000006275521
 When selector lever is P or N, power is supplied to starter relay and starter control relay by TCM. And BCM
and IPDM E/R (CPU) detect selector lever P/N condition by the inputted signal.
 When starter operating condition is satisfied, IPDM E/R tu rns starter control relay ON by starter control relay
control signal.
 When engine cranking condition is satisfied, BCM turns starter relay ON by starter relay control signal.
 Then battery power is supplied to starter motor (“S” terminal) through starter control relay and starter relay. And IPDM E/R (CPU) detect starter re lay condition by the inputted signal.
JMBIA2983GB
Revision: 2010 May2011 QX56

STARTING SYSTEMSTR-7
< WIRING DIAGRAM >
C
DE
F
G H
I
J
K L
M A
STR
NP
O
WIRING DIAGRAM
STARTING SYSTEM
Wiring DiagramINFOID:0000000006275522
JCBWM2110GB
Revision: 2010 May2011 QX56