ignition INFINITI QX56 2007 Factory Service Manual

DI-68
< SERVICE INFORMATION >
REAR VIEW MONITOR
1. Turn ignition switch ON.
2. Shift A/T selector lever to R position.
Does back-up lamp illuminate?
YES >> GO TO 2.
NO >> Check back-up lamp system. Refer to LT- 8 0
.
2.CHECK REVERSE POSITION INPUT SIGNAL
With CONSULT-II
Select “DATA MONITOR” of “REARVIEW CAMERA”. Operate igni-
tion switch with “R POSI SIG” of “DATA MONITOR” and check oper-
ate status.
Without CONSULT-II
1. Turn ignition switch OFF.
2. Disconnect rear view camera control unit connector.
3. Turn ignition switch ON.
4. Shift A/T selector lever to R position.
5. Check voltage between rear view camera control unit harness
connector B73 terminal 4 and ground.
OK or NG
OK >> GO TO 3.
NG >> Check harness for open or short between rear view
camera control unit and back-up lamp relay.
3.CHECK DISPLAY CONTROL UNIT OUTPUT SIGNAL
1. Turn ignition switch OFF.
2. Disconnect rear view camera control unit connector.
3. Turn ignition switch ON.
4. Check voltage between rear view camera control unit harness
connector B73 terminal 5 and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.CHECK DISPLAY CONTROL UNIT CIRCUIT
SKIA7147E
Battery voltage should exist.
SKIA5086E
Voltage : Approx. 5V
SKIA7148E

REAR VIEW MONITOR
DI-69
< SERVICE INFORMATION >
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1. Turn ignition switch OFF.
2. Disconnect display control unit connector.
3. Check continuity between rear view camera control unit harness
connector B73 terminal 5 and display control unit harness con-
nector M94 terminal 8.
4. Check continuity between rear view camera control unit harness
connector B73 terminal 5 and ground.
OK or NG
OK >> Replace display control unit. Refer to AV-145, "Removal and Installation".
NG >> Repair harness or connector.
5.CHECK AV CONTROL SIGNAL
1. Turn ignition switch OFF.
2. Connect rear view camera control unit connector.
3. Turn ignition switch ON.
4. Shift A/T selector lever to R position.
5. Check voltage between rear view camera control unit harness
connector B73 terminal 5 and ground.
OK or NG
OK >> GO TO 6.
NG >> Replace rear view camera control unit. Refer to DI-71,
"Removal and Installation of Rear View Camera Control Unit".
6.CHECK REAR VIEW CAMERA OPEN CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect rear view camera and rear view camera control unit
connectors.
3. Check continuity between rear view camera control unit harness
connector B73 terminal 8 and rear view camera harness con-
nector D504 terminal 1.
4. Check continuity between rear view camera control unit harness
connector B73 terminal 9 and rear view camera harness con-
nector D504 terminal 4.
5. Check continuity between rear view camera control unit harness connector B73 terminal 10 and rear view
camera harness connector D504 terminal 3.
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector.
7.CHECK REAR VIEW CAMERA SHORT CIRCUITContinuity should exist.
Continuity should not exist.
SKIA7149E
Voltage : Approx. 0V
SKIA7150E
Continuity should exist.
Continuity should exist.
Continuity should exist.
SKIA5095E

DI-70
< SERVICE INFORMATION >
REAR VIEW MONITOR
1. Check continuity between rear view camera control unit harness
connector B73 terminal 8 and ground.
2. Check continuity between rear view camera control unit harness
connector B73 terminal 9 and ground.
3. Check continuity between rear view camera control unit harness
connector B73 terminal 10 and ground.
OK or NG
OK >> GO TO 8.
NG >> Repair harness on connector.
8.CHECK POWER SUPPLY AND GROUND CIRCUIT
Check power supply and ground circuit. Refer to DI-67, "
Power Supply and Ground Circuit Inspection".
OK or NG
OK >> GO TO 9.
NG >> Repair or replace power supply or ground circuit.
9.CHECK REAR VIEW CAMERA CONTROL UNIT OUTPUT SIGNAL
1. Connect rear view camera control unit connector.
2. Turn ignition switch ON.
3. Shift A/T selector lever to R position.
4. Check voltage between rear view camera control unit harness
connector B73 terminal 8 and ground.
OK or NG
OK >> GO TO 10.
NG >> Replace the rear view camera control unit. Refer to DI-
71, "Removal and Installation of Rear View Camera
Control Unit".
10.CHECK REAR VIEW CAMERA SIGNAL
1. Turn ignition switch OFF.
2. Connect rear view camera connector.
3. Turn ignition switch ON.
4. Shift A/T selector lever to R position.
5. Check voltage signal between rear view camera control unit har-
ness connector B73 terminal 10 and ground.
OK or NG
OK >> GO TO 11.
NG >> Replace the rear view camera. Refer to DI-72, "
Removal and Installation of Rear View Camera".
11 .CHECK COMPOSITE SIGNAL OPEN OR SHORT CIRCUITContinuity should not exist.
Continuity should not exist.
Continuity should not exist.
SKIA5098E
Voltage : Approx. 6V
SKIA5099E
10 - Ground:SKIA5100E
SKIA4894E

REAR VIEW MONITOR
DI-71
< SERVICE INFORMATION >
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1. Turn ignition switch OFF.
2. Disconnect rear view camera control unit connector and display
unit connector.
3. Check continuity between rear view camera control unit harness
connector B73 terminal 12 and display unit harness connector
M93 terminal 15.
4. Check continuity between rear view camera control unit harness
connector B73 terminal 12 and ground.
OK or NG
OK >> GO TO 12.
NG >> Repair harness or connector.
12.CHECK COMPOSITE SIGNAL GROUND CIRCUIT
1. Check continuity between rear view camera control unit harness
connector B73 terminal 11 and display unit harness connector
M93 terminal 4.
2. Check continuity between rear view camera control unit harness
connector B73 terminal 11 and ground.
OK or NG
OK >> GO TO 13.
NG >> Repair harness or connector.
13.CHECK REAR VIEW CAMERA CONTROL UNIT COMPOSITE SIGNAL
1. Connect rear view camera control unit connector and display
unit connector.
2. Turn ignition switch ON.
3. Check voltage signal between rear view camera control unit har-
ness connector B73 terminal 12 and ground.
OK or NG
OK >> Replace the display unit. Refer to AV-145, "Removal and Installation".
NG >> Replace the rear view camera control unit. Refer to DI-71, "
Removal and Installation of Rear View
Camera Control Unit".
Removal and Installation of Rear View Camera Control UnitINFOID:0000000003533548
REMOVAL
1. Disconnect battery negative terminal.Continuity should exist.
Continuity should not exist.
WKIA1825E
Continuity should exist.
Continuity should not exist.
WKIA1826E
12 - Ground:
WKIA1827E
SKIA4896E

EC-1
ENGINE
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SECTION EC
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CONTENTS
ENGINE CONTROL SYSTEM
SERVICE INFORMATION ............................9
INDEX FOR DTC .................................................9
DTC No. Index ..........................................................9
Alphabetical Index ...................................................12
PRECAUTIONS ..................................................17
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .................................................................
17
On Board Diagnosis (OBD) System of Engine and
A/T ...........................................................................
17
Precaution ...............................................................17
PREPARATION ..................................................21
Special Service Tool ...............................................21
Commercial Service Tool ........................................22
ENGINE CONTROL SYSTEM ............................24
Schematic ...............................................................24
Multiport Fuel Injection (MFI) System .....................24
Electronic Ignition (EI) System ................................27
Fuel Cut Control (at No Load and High Engine
Speed) .....................................................................
27
AIR CONDITIONING CUT CONTROL ...............29
Input/Output Signal Chart ........................................29
System Description .................................................29
AUTOMATIC SPEED CONTROL DEVICE
(ASCD) ...............................................................
30
System Description .................................................30
Component Description ...........................................31
CAN COMMUNICATION ....................................32
System Description .................................................32
EVAPORATIVE EMISSION SYSTEM ................33
Description ..............................................................33
Component Inspection ............................................35
Removal and Installation .........................................37
How to Detect Fuel Vapor Leakage ........................37
ON BOARD REFUELING VAPOR RECOV-
ERY (ORVR) ......................................................
40
System Description ..................................................40
Diagnosis Procedure ...............................................40
Component Inspection .............................................42
POSITIVE CRANKCASE VENTILATION .........45
Description ...............................................................45
Component Inspection .............................................45
IVIS (INFINITI VEHICLE IMMOBILIZER SYS-
TEM-NATS) .......................................................
47
Description ...............................................................47
ON BOARD DIAGNOSTIC (OBD) SYSTEM ....48
Introduction ..............................................................48
Two Trip Detection Logic .........................................48
Emission-related Diagnostic Information .................49
Malfunction Indicator Lamp (MIL) ............................63
OBD System Operation Chart .................................65
BASIC SERVICE PROCEDURE .......................71
Basic Inspection ......................................................71
Idle Speed and Ignition Timing Check .....................75
Procedure After Replacing ECM .............................77
VIN Registration ......................................................77
Accelerator Pedal Released Position Learning .......77
Throttle Valve Closed Position Learning .................77
Idle Air Volume Learning .........................................78
Fuel Pressure Check ...............................................80
TROUBLE DIAGNOSIS ....................................82
Trouble Diagnosis Introduction ................................82
DTC Inspection Priority Chart ..................................87
Fail-Safe Chart ........................................................88
Symptom Matrix Chart .............................................90
Engine Control Component Parts Location .............94
Vacuum Hose Drawing ..........................................100
Circuit Diagram ......................................................101
ECM Harness Connector Terminal Layout ............103
ECM Terminal and Reference Value .....................103

EC-8
DTC Confirmation Procedure ................................567
Wiring Diagram ......................................................569
Diagnosis Procedure .............................................570
Component Inspection ...........................................572
Removal and Installation .......................................573
DTC P2135 TP SENSOR .................................574
Component Description .........................................574
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
574
On Board Diagnosis Logic .....................................574
DTC Confirmation Procedure ................................574
Wiring Diagram ......................................................576
Diagnosis Procedure .............................................577
Component Inspection ...........................................579
Removal and Installation .......................................580
DTC P2138 APP SENSOR ..............................581
Component Description .........................................581
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
581
On Board Diagnosis Logic .....................................581
DTC Confirmation Procedure ................................582
Wiring Diagram ......................................................583
Diagnosis Procedure .............................................584
Component Inspection ...........................................587
Removal and Installation .......................................587
DTC P2A00, P2A03 A/F SENSOR 1 ...............588
Component Description .........................................588
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
588
On Board Diagnosis Logic .....................................588
DTC Confirmation Procedure ................................588
Wiring Diagram ......................................................590
Diagnosis Procedure .............................................593
Removal and Installation .......................................596
ASCD BRAKE SWITCH ..................................597
Component Description .........................................597
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
597
Wiring Diagram ......................................................598
Diagnosis Procedure .............................................599
Component Inspection ...........................................602
ASCD INDICATOR ..........................................603
Component Description .........................................603
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
603
Wiring Diagram ......................................................604
Diagnosis Procedure .............................................604
ELECTRICAL LOAD SIGNAL .........................606
Description .............................................................606
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
606
Diagnosis Procedure .............................................606
FUEL INJECTOR ..............................................608
Component Description ........................................608
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
608
Wiring Diagram .....................................................609
Diagnosis Procedure .............................................610
Component Inspection ..........................................612
Removal and Installation .......................................612
FUEL PUMP .....................................................613
Description ............................................................613
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
613
Wiring Diagram .....................................................614
Diagnosis Procedure .............................................615
Component Inspection ..........................................617
Removal and Installation .......................................618
ICC BRAKE SWITCH .......................................619
Component Description ........................................619
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
619
Wiring Diagram .....................................................620
Diagnosis Procedure .............................................621
Component Inspection ..........................................624
IGNITION SIGNAL ............................................626
Component Description ........................................626
Wiring Diagram .....................................................627
Diagnosis Procedure .............................................632
Component Inspection ..........................................635
Removal and Installation .......................................637
REFRIGERANT PRESSURE SENSOR ...........638
Component Description ........................................638
Wiring Diagram .....................................................639
Diagnosis Procedure .............................................640
Removal and Installation .......................................642
MIL AND DATA LINK CONNECTOR ...............643
Wiring Diagram .....................................................643
SERVICE DATA AND SPECIFICATIONS
(SDS) ................................................................
645
Fuel Pressure ........................................................645
Idle Speed and Ignition Timing .............................645
Calculated Load Value ..........................................645
Mass Air Flow Sensor ...........................................645
Intake Air Temperature Sensor .............................645
Engine Coolant Temperature Sensor ...................645
A/F Sensor 1 Heater .............................................645
Heated Oxygen sensor 2 Heater ..........................645
Crankshaft Position Sensor (POS) .......................646
Camshaft Position Sensor (PHASE) .....................646
Throttle Control Motor ...........................................646
Fuel Injector ..........................................................646
Fuel Pump .............................................................646

PRECAUTIONS
EC-17
< SERVICE INFORMATION >
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PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000003531580
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity 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 SRS and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inoperative, 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 incorrect removal and installation of the SRS, can lead to personal
injury caused by unintentional activation of the system. For removal of Spiral Cable and Air Bag
Module, see the SRS section.
• Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or har-
ness connectors.
On Board Diagnosis (OBD) System of Engine and A/TINFOID:0000000003531581
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
• Be sure to turn the ignition switch OFF and disconnect the negative battery cable before any repair
or inspection work. The open/short circuit of related switches, sensors, solenoid valves, etc. will
cause the MIL to light up.
• Be sure to connect and lock the connectors securely after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
• Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For description and how to disconnect, refer to PG-66
.
• Be sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to light up due to the short circuit.
• Be sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfunction of the EVAP system or fuel injection system,
etc.
• Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
PrecautionINFOID:0000000003531582
•Always use a 12 volt battery as power source.
•Do not attempt to disconnect battery cables while engine is
running.
•Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
•Before removing parts, turn ignition switch OFF and then dis-
connect negative battery cable.
SEF289H

ENGINE CONTROL SYSTEM
EC-27
< SERVICE INFORMATION >
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This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration, operation of the engine at excessively high speeds or oper-
ation of the vehicle at excessively high speed.
Electronic Ignition (EI) SystemINFOID:0000000003531587
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
Firing order: 1 - 8 - 7 - 3 - 6 - 5 - 4 -2
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor signal. Comput-
ing this information, ignition signals are transmitted to the power transistor.
During the following conditions, the ignition timing is revised by the ECM according to the other data stored in
the ECM.
• At starting
• During warm-up
•At idle
• At low battery voltage
• During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Fuel Cut Control (at No Load and High Engine Speed)INFOID:0000000003531588
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
2
Piston position
Ignition timing
controlPower transistor Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Knock sensor Engine knocking
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
2
Wheel sensor
Vehicle speed*1
Sensor Input signal to ECM ECM function Actuator
Park/neutral position (PNP) switch Neutral position
Fuel cut control Fuel injector Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
Wheel sensor Vehicle speed*

EC-38
< SERVICE INFORMATION >
EVAPORATIVE EMISSION SYSTEM
WITH CONSULT-II
1. Attach the EVAP service port adapter securely to the EVAP service port.
2. Also attach the pressure pump and hose to the EVAP service port adapter.
3. Turn ignition switch ON.
4. Select the “EVAP SYSTEM CLOSE” of “WORK SUPPORT
MODE” with CONSULT-II.
5. Touch “START”. A bar graph (Pressure indicating display) will
appear on the screen.
6. Apply positive pressure to the EVAP system until the pressure
indicator reaches the middle of the bar graph.
7. Remove EVAP service port adapter and hose with pressure
pump.
8. Locate the leak using a leak detector. Refer to EC-33, "
Descrip-
tion".
WITHOUT CONSULT-II
1. Attach the EVAP service port adapter securely to the EVAP ser-
vice port.
PEF838U
PEF917U
SEF200U
BBIA0366E

IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-NATS)
EC-47
< SERVICE INFORMATION >
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IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-NATS)
DescriptionINFOID:0000000003531603
•If the security indicator lights up with the ignition switch in
the ON position or “NATS MALFUNCTION” is displayed on
“SELF-DIAG RESULTS” screen, perform self-diagnostic
results mode with CONSULT-II using NATS program card.
Refer to BL-116
.
•Confirm no self-diagnostic results of IVIS (NATS) is displayed
before touching “ERASE” in “SELF-DIAG RESULTS” mode
with CONSULT-II.
•When replacing ECM, initialization of IVIS (NATS) system and
registration of all IVIS (NATS) ignition key IDs must be carried
out with CONSULT-II using NATS program card.
Therefore, be sure to receive all keys from vehicle owner.
Regarding the procedures of IVIS (NATS) initialization and all IVIS (NATS) ignition key ID registration,
refer to CONSULT-II operation manual, IVIS/NVIS.
SEF543X