2009 INFINITI QX56 ignition

PRECAUTIONSDLN-203
< PRECAUTION > [FRONT FINAL DRIVE: M205]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005875034
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
 To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
 Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the SR section.
 Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
 When working near the Airbag Diagnosis Sensor Un it or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or el ectric power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
 When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minutes before performing any service.
Precaution Necessary for Steering Wh eel Rotation After Battery Disconnect
INFOID:0000000005875035
NOTE:
 This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
 Remove and install all control units after disconnecti ng both battery cables with the ignition knob in the
″ LOCK ″ position.
 Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS , an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
Revision: December 20092009 QX56

DLN-204
< PRECAUTION >[FRONT FINAL DRIVE: M205]
PRECAUTIONS
5. When the repair work is completed, return the ignition switch to the
″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of a ll control units using CONSULT-III.
Precaution for Servicing Front Final DriveINFOID:0000000004193536
 Before starting diagnosis of the vehicle, understand the symptoms well. Perform correct and systematic
operations.
 Check for the correct installation status prior to re moval or disassembly. When matching marks are required,
be certain they do not interfere with the f unction of the parts they are applied to.
 Overhaul should be done in a clean work area, a dust proof area is recommended.
 Before disassembly, completely remove sand and mud from the exterior of the unit, preventing them from
entering into the unit during disassembly or assembly.
 Always use shop paper for cleaning the inside of components.
 Avoid using cotton gloves or a shop cloth to prevent the entering of lint.
 Check appearance of the disassembled parts for dam age, deformation, and abnormal wear. Replace them
with new ones if necessary.
 Gaskets, seals and O-rings should be replaced any time the unit is disassembled.
 Clean and flush the parts sufficiently and blow them dry.
 Be careful not to damage sliding surfaces and mating surfaces.
 When applying sealant, remove the old sealant from the mating surface; then remove any moisture, oil, and
foreign materials from the application and mating surfaces.
 In principle, tighten nuts or bolts gradually in severa l steps working diagonally from inside to outside. If a
tightening sequence is specified, observe it.
 During assembly, observe the specified tightening torque.
 Add new differential gear oil, petroleum jelly, or multi-purpose grease, as specified.
Revision: December 20092009 QX56

DLN-236
< PRECAUTION >[REAR FINAL DRIVE: R230]
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint S
ystem (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005877756
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
 To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISS AN/INFINITI dealer.
 Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
 Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
 When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
 When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000005877757
NOTE:
 This Procedure is applied only to models with Intelli gent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
 Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
 Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
Revision: December 20092009 QX56

PRECAUTIONSDLN-237
< PRECAUTION > [REAR FINAL DRIVE: R230]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
5. When the repair work is completed, return the ignition switch to the ″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of al l control units using CONSULT-III.
Precaution for Servicing Rear Final DriveINFOID:0000000004193549
 Before starting diagnosis of the vehicle, understand the symptoms well. Perform correct and systematic
operations.
 Check for the correct installation status prior to removal or disassembly. When matching marks are required,
be certain they do not interfere with the function of the parts they are applied to.
 Overhaul should be done in a clean work area, a dust proof area is recommended.
 Before disassembly, completely remove sand and mud fr om the exterior of the unit, preventing them from
entering into the unit during disassembly or assembly.
 Always use shop paper for cleaning the inside of components.
 Avoid using cotton gloves or a shop cloth to prevent the entering of lint.
 Check appearance of the disassembled parts for damage, deformation, and abnormal wear. Replace them with new ones if necessary.
 Gaskets, seals and O-rings should be replaced any time the unit is disassembled.
 Clean and flush the parts sufficiently and blow them dry.
 Be careful not to damage sliding surfaces and mating surfaces.
 When applying sealant, remove the old sealant from t he mating surface; then remove any moisture, oil, and
foreign materials from the application and mating surfaces.
 In principle, tighten nuts or bolts gradually in several steps working diagonally from inside to outside. If a tightening sequence is specified, observe it.
 During assembly, observe the specified tightening torque.
 Add new differential gear oil, petroleum jell y, or multi-purpose grease, as specified.
Revision: December 20092009 QX56

EC-1
ENGINE
C
DE
F
G H
I
J
K L
M
SECTION EC
A
EC
N
O P
CONTENTS
ENGINE CONTROL SYSTEM
VK56DE
BASIC INSPECTION ....... .............................
8
DIAGNOSIS AND REPAIR WORKFLOW ..... .....8
Trouble Diagnosis Introduction ........................... ......8
INSPECTION AND ADJUSTMENT ....................13
Basic Inspection .................................................. ....13
Idle Speed and Ignition Timing Check ....................17
Procedure After Replacing ECM .............................17
VIN Registration ......................................................17
Accelerator Pedal Released Position Learning .......18
Throttle Valve Closed Position Learning .................18
Idle Air Volume Learning .........................................18
FUNCTION DIAGNOSIS ..............................21
ENGINE CONTROL SYSTEM ........................ ....21
System Diagram .................................................. ....21
Engine Control Component Parts Location .............22
MULTIPORT FUEL INJECTION SYSTEM .........28
System Description ............................................. ....28
ELECTRIC IGNITION SYSTEM ..................... ....31
System Description ............................................. ....31
AIR CONDITIONING CUT CONTROL ...............32
Input/Output Signal Chart .................................... ....32
System Description .................................................32
AUTOMATIC SPEED CONTROL DEVICE
(ASCD) ...............................................................
33
System Description ............................................. ....33
Component Description ...........................................34
CAN COMMUNICATION ....................................35
System Description ............................................. ....35
COOLING FAN CONTROL ................................36
Description .......................................................... ....36
EVAPORATIVE EMISSION SYSTEM ...............37
Description ........................................................... ....37
INTAKE VALVE TIMING CONTROL ................40
Description ...............................................................40
ON BOARD DIAGNOSTIC (OBD) SYSTEM ....41
Introduction ..............................................................41
Two Trip Detection Logic .........................................41
Emission-related Diagnostic Information .................42
Malfunction Indicator Lamp (MIL) ............................55
OBD System Operation Chart .................................58
CONSULT-III Function (ENGINE) ...........................63
Generic Scan Tool (GST) Function .........................72
COMPONENT DIAGNOSIS .........................74
TROUBLE DIAGNOSIS - SPECIFICATION
VALUE ...............................................................
74
Description ........................................................... ....74
Testing Condition .....................................................74
Inspection Procedure ...............................................74
Diagnosis Procedure ...............................................75
POWER SUPPLY AND GROUND CIRCUIT ....82
Diagnosis Procedure ...............................................82
Ground Inspection ...................................................85
U1000, U1001 CAN COMM CIRCUIT ...............86
Description ...............................................................86
On Board Diagnosis Logic .......................................86
DTC Confirmation Procedure ..................................86
Diagnosis Procedure ...............................................86
P0011, P0021 IVT CONTROL ...........................87
On Board Diagnosis Logic .......................................87
DTC Confirmation Procedure ..................................87
Diagnosis Procedure ...............................................88
Component Inspection .............................................92
P0031, P0032, P0051, P0052 A/F SENSOR 1
HEATER ............................................................
94
Revision: December 20092009 QX56

EC-6
On Board Diagnosis Logic .....................................351
DTC Confirmation Procedure ................................351
Diagnosis Procedure .............................................351
P2101 ELECTRIC THROTTLE CONTROL
FUNCTION .......................................................
354
Description ........................................................... ..354
On Board Diagnosis Logic .....................................354
DTC Confirmation Procedure ................................354
Diagnosis Procedure .............................................354
Component Inspection ...........................................357
P2118 THROTTLE CONTROL MOTOR ..........358
Component Description ....................................... ..358
On Board Diagnosis Logic .....................................358
DTC Confirmation Procedure ................................358
Diagnosis Procedure .............................................358
Component Inspection ...........................................359
P2119 ELECTRIC THROTTLE CONTROL
ACTUATOR .....................................................
360
Component Description ....................................... ..360
On Board Diagnosis Logic .....................................360
DTC Confirmation Procedure ................................360
Diagnosis Procedure .............................................361
P2122, P2123 APP SENSOR ..........................362
Component Description ....................................... ..362
On Board Diagnosis Logic .....................................362
DTC Confirmation Procedure ................................362
Diagnosis Procedure .............................................362
Component Inspection ...........................................364
P2127, P2128 APP SENSOR ..........................365
Component Description ....................................... ..365
On Board Diagnosis Logic .....................................365
DTC Confirmation Procedure ................................365
Diagnosis Procedure .............................................365
Component Inspection ...........................................368
P2135 TP SENSOR .........................................369
Component Description ....................................... ..369
On Board Diagnosis Logic .....................................369
DTC Confirmation Procedure ................................369
Diagnosis Procedure .............................................369
Component Inspection ...........................................372
P2138 APP SENSOR ......................................373
Component Description ....................................... ..373
On Board Diagnosis Logic .....................................373
DTC Confirmation Procedure ................................373
Diagnosis Procedure .............................................374
Component Inspection ...........................................376
P2A00, P2A03 A/F SENSOR 1 .......................377
Component Description ....................................... ..377
On Board Diagnosis Logic .....................................377
DTC Confirmation Procedure ................................377
Diagnosis Procedure .............................................378
ASCD BRAKE SWITCH ................................. .383
Component Description ....................................... .383
Diagnosis Procedure .............................................383
Component Inspection ..........................................386
ASCD INDICATOR ...........................................387
Component Description ....................................... .387
Diagnosis Procedure .............................................387
COOLING FAN .................................................388
Diagnosis Procedure ............................................ .388
Component Inspection ..........................................388
ELECTRICAL LOAD SIGNAL ..........................390
Description ........................................................... .390
Diagnosis Procedure .............................................390
FUEL INJECTOR ..............................................392
Component Description ....................................... .392
Diagnosis Procedure .............................................392
Component Inspection ..........................................394
FUEL PUMP .....................................................395
Description ........................................................... .395
Diagnosis Procedure .............................................395
Component Inspection ..........................................398
ICC BRAKE SWITCH ..................................... ..399
Component Description ....................................... .399
Diagnosis Procedure .............................................399
Component Inspection ..........................................402
IGNITION SIGNAL ............................................404
Component Description ....................................... .404
Diagnosis Procedure .............................................404
Component Inspection ..........................................407
ON BOARD REFUELING VAPOR RECOV-
ERY (ORVR) .....................................................
409
System Description .............................................. .409
Diagnosis Procedure .............................................409
Component Inspection ..........................................411
POSITIVE CRANKCASE VENTILATION .........414
Description ........................................................... .414
Component Inspection ..........................................414
REFRIGERANT PRESSURE SENSOR ...........416
Component Description ....................................... .416
Diagnosis Procedure .............................................416
ECU DIAGNOSIS ......................................419
ECM ................................................................ ..419
CONSULT-lll Reference Value in Data Monitor
Mode .................................................................... .
419
ECM Harness Connector Terminal Layout ...........422
ECM Terminal and Reference Value ....................422
Wiring Diagram - ENGINE CONTROL SYSTEM - .432
Fail-Safe Chart ......................................................453
DTC Inspection Priority Chart ...............................455
DTC Index .............................................................456
Emission-related Diagnostic Information ..............460
Revision: December 20092009 QX56

EC-7
C
DE
F
G H
I
J
K L
M
EC A
N
O P
SYMPTOM DIAGNOSIS ..... .......................475
ENGINE CONTROL SYSTEM SYMPTOMS .. ..475
Symptom Matrix Chart ........................................ ..475
NORMAL OPERATING CONDITION ...............479
Fuel Cut Control (at No Load and High Engine
Speed) ................................................................. ..
479
PRECAUTION ............................................480
PRECAUTIONS .............................................. ..480
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ..
480
On Board Diagnosis (OBD) System of Engine and
A/T .........................................................................
480
Precaution .............................................................481
PREPARATION .........................................484
PREPARATION .............................................. ..484
Special Service Tool ........................................... ..484
Commercial Service Tool ......................................485
ON-VEHICLE MAINTENANCE ..................487
FUEL PRESSURE .......................................... ..487
Fuel Pressure Check ........................................... ..487
EVAP LEAK CHECK ........................................489
How to Detect Fuel Vapor Leakage .................... ..489
ON-VEHICLE REPAIR ...............................491
EVAP CANISTER ............................................491
Removal and Installation ..................................... ..491
Component Inspection ...........................................491
INTAKE VALVE TIMING CONTROL ..............492
Intake Valve Timing Control Solenoid Valve (LH) ..492
Intake Valve Timing Cont rol Solenoid Valve (RH) ..492
Intake Valve Timing Control Position Sensor (LH) ..493
Intake Valve Timing Control Position Sensor (RH) ..493
Camshaft Position Sensor (PHASE) .....................493
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... ...........................................
495
SERVICE DATA AND SPECIFICATIONS
(SDS) ...............................................................
495
Fuel Pressure ...................................................... ..495
Idle Speed and Ignition Timing ..............................495
Calculated Load Value ..........................................495
Mass Air Flow Sensor ............................................495
Intake Air Temperature Sensor .............................495
Engine Coolant Temperature Sensor ....................495
A/F Sensor 1 Heater ..............................................495
Heated Oxygen sensor 2 Heater ...........................496
Crankshaft Position Sensor (POS) ........................496
Camshaft Position Sensor (PHASE) .....................496
Throttle Control Motor ............................................496
Fuel Injector ...........................................................496
Fuel Pump .............................................................496
Revision: December 20092009 QX56

EC-8
< BASIC INSPECTION >[VK56DE]
DIAGNOSIS AND REPAIR WORKFLOW
BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
Trouble Diagnosis IntroductionINFOID:0000000003771293
INTRODUCTION
The engine has an ECM to control major systems such as fuel con-
trol, ignition control, idle air control system, etc. The ECM accepts
input signals from sensors and instantly drives actuators. It is essen-
tial that both input and output signals are proper and stable. At the
same time, it is important that there are no malfunctions such as vac-
uum leaks, fouled spark plugs, or
other malfunctions with the engine.
It is much more difficult to diagnose an incident that occurs intermit-
tently rather than continuously. Most intermittent incidents are
caused by poor electric connections or improper wiring. In this case,
careful checking of suspected circuits may help prevent the replace-
ment of good parts.
A visual check only may not find the cause of the incidents. A road
test with CONSULT-III (or GST) or a circuit tester connected should
be performed. Follow the Work Flow on "WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a dr iveability complaint. The cus-
tomer can supply good information about such incidents, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A Di agnostic Worksheet like the example
on "Worksheet Sample" should be used.
Start your diagnosis by looking fo r conventional malfunctions first.
This will help troubleshoot driveability malfunctions on an electroni-
cally controlled engine vehicle.
WORK FLOW
MEF036D
SEF233G
SEF234G
Revision: December 20092009 QX56