fuel pressure INFINITI QX56 2007 Factory User Guide

DI-18
< SERVICE INFORMATION >
COMBINATION METERS
Self-diagnostic results content
No malfunction detected>>GO TO 2.
Malfunction detected>>GO TO PG-18, "
CONSULT-II Function (IPDM E/R)".
2.CHECK IPDM E/R INPUT SIGNAL
Select "IPDM E/R" on CONSULT-II. Operate ignition switch with "OIL
P SW" of "DATA MONITOR" and check operation status.
OK or NG
OK >> Replace combination meter. Refer to IP-10, "Removal
and Installation".
NG >> GO TO 3.
3.CHECK OIL PRESSURE SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector E122 and oil pressure switch
connector F4.
3. Check continuity between IPDM E/R harness connector E122 (A) terminal 42 and oil pressure switch harness connector F4 (B)
terminal 1.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4.CHECK OIL PRESSURE SWITCH
Check oil pressure switch. Refer to DI-21, "
Electrical Component Inspection".
OK or NG
OK >> Replace IPDM E/R. Refer to PG-28, "Removal and Installation of IPDM E/R".
NG >> Replace oil pressure switch.
Water Temperature Signal InspectionINFOID:0000000003533493
1.CHECK ECM SELF-DIAGNOSIS
Perform ECM self-diagnosis. Refer to E C - 111 , "
CONSULT-II Function (ENGINE)".
OK or NG
OK >> Replace the combination meter. Refer to IP-10, "Removal and Installation".
NG >> Perform "Diagnostic procedure" for displayed DTC. Refer to EC-82
.
Engine Speed Signal InspectionINFOID:0000000003533494
1.CHECK ECM SELF-DIAGNOSIS
Perform ECM self-diagnosis. Refer to E C - 111 , "
CONSULT-II Function (ENGINE)".
OK or NG
OK >> Replace the combination meter. Refer to IP-10, "Removal and Installation".
NG >> Perform "Diagnostic procedure" for displayed DTC. Refer to EC-82
.
Fuel Level Sensor Unit InspectionINFOID:0000000003533495
FUEL LEVEL SENSOR UNIT
The following symptoms do not indicate a malfunction.When ignition switch is in ON
position (Engine stopped)
: OIL P SW CLOSE
When engine running : OIL P SW OPEN
LKIA0403E
Continuity should exist.
WKIA5607E

COMBINATION METERS
DI-21
< SERVICE INFORMATION >
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4.CHECK POINTER MOVEMENT TO EMPTY-POSITION
During driving, does the fuel gauge move gradually toward empty-position?
YES or NO
YES >> Check the fuel level sensor unit. Refer to DI-21, "Electrical Component Inspection".
NO >> Check fuel level sensor unit installation, and determine whether the float arm interferes or binds
with any of the internal components in the fuel tank.
Electrical Component InspectionINFOID:0000000003533498
FUEL LEVEL SENSOR UNIT CHECK
For removal, refer to FL-5, "Removal and Installation".
Check Fuel Level Sensor Unit and Fuel Pump
Check resistance between fuel level sensor unit and fuel pump con-
nector terminals 2 and 5.
*1 and *2: When float rod is in contact with stopper.
OIL PRESSURE SWITCH CHECK
Check continuity between the oil pressure switch and body ground.
Removal and Installation of Combination MeterINFOID:0000000003533499
Refer to "Removal and Installation of Combination Meter" for removal and installation procedures.
Terminals Float position mm (in)Resistance
value Ω
(Approx.)
25*1 Empty 25.86 (1.02) 81.66
*2 Full 254.6 (10.02) 6.98
LKIA0402E
ConditionOil pressure
kPa (kg/cm2, psi)Continuity
Engine stopped Less than 29 (0.3, 4) Yes
Engine running More than 29 (0.3, 4) No
ELF0044D

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-5
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ECA
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P CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
379
On Board Diagnosis Logic ....................................379
DTC Confirmation Procedure ................................379
Wiring Diagram .....................................................381
Diagnosis Procedure .............................................382
Component Inspection ..........................................384
DTC P0448 EVAP CANISTER VENT CON-
TROL VALVE ...................................................
386
Component Description .........................................386
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
386
On Board Diagnosis Logic ....................................386
DTC Confirmation Procedure ................................386
Wiring Diagram .....................................................388
Diagnosis Procedure .............................................389
Component Inspection ..........................................390
DTC P0451 EVAP CONTROL SYSTEM
PRESSURE SENSOR ......................................
392
Component Description .........................................392
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
392
On Board Diagnosis Logic ....................................392
DTC Confirmation Procedure ................................392
Diagnosis Procedure .............................................393
Component Inspection ..........................................394
DTC P0452 EVAP CONTROL SYSTEM
PRESSURE SENSOR ......................................
395
Component Description .........................................395
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
395
On Board Diagnosis Logic ....................................395
DTC Confirmation Procedure ................................395
Wiring Diagram .....................................................397
Diagnosis Procedure .............................................398
Component Inspection ..........................................400
DTC P0453 EVAP CONTROL SYSTEM
PRESSURE SENSOR ......................................
401
Component Description .........................................401
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
401
On Board Diagnosis Logic ....................................401
DTC Confirmation Procedure ................................401
Wiring Diagram .....................................................403
Diagnosis Procedure .............................................404
Component Inspection ..........................................407
DTC P0455 EVAP CONTROL SYSTEM ..........408
On Board Diagnosis Logic ....................................408
DTC Confirmation Procedure ................................408
Diagnosis Procedure .............................................410
DTC P0456 EVAP CONTROL SYSTEM ..........415
On Board Diagnosis Logic ....................................415
DTC Confirmation Procedure ................................416
Overall Function Check .........................................416
Diagnosis Procedure .............................................417
DTC P0460 FUEL LEVEL SENSOR ...............423
Component Description .........................................423
On Board Diagnosis Logic .....................................423
DTC Confirmation Procedure ................................423
Diagnosis Procedure .............................................424
Removal and Installation .......................................424
DTC P0461 FUEL LEVEL SENSOR ...............425
Component Description .........................................425
On Board Diagnosis Logic .....................................425
Overall Function Check .........................................425
Diagnosis Procedure .............................................426
Removal and Installation .......................................426
DTC P0462, P0463 FUEL LEVEL SENSOR
CIRCUIT ..........................................................
427
Component Description .........................................427
On Board Diagnosis Logic .....................................427
DTC Confirmation Procedure ................................427
Diagnosis Procedure .............................................428
Removal and Installation .......................................428
DTC P0500 VSS ..............................................429
Description .............................................................429
On Board Diagnosis Logic .....................................429
DTC Confirmation Procedure ................................429
Overall Function Check .........................................430
Diagnosis Procedure .............................................430
DTC P0506 ISC SYSTEM ...............................431
Description .............................................................431
On Board Diagnosis Logic .....................................431
DTC Confirmation Procedure ................................431
Diagnosis Procedure .............................................431
DTC P0507 ISC SYSTEM ...............................433
Description .............................................................433
On Board Diagnosis Logic .....................................433
DTC Confirmation Procedure ................................433
Diagnosis Procedure .............................................433
DTC P0550 PSP SENSOR ..............................435
Component Description .........................................435
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
435
On Board Diagnosis Logic .....................................435
DTC Confirmation Procedure ................................435
Wiring Diagram ......................................................436
Diagnosis Procedure .............................................437
Component Inspection ...........................................438
Removal and Installation .......................................439
DTC P0603 ECM POWER SUPPLY ...............440
Component Description .........................................440
On Board Diagnosis Logic .....................................440
DTC Confirmation Procedure ................................440
Wiring Diagram ......................................................441
Diagnosis Procedure .............................................442

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

PREPARATION
EC-21
< SERVICE INFORMATION >
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PREPARATION
Special Service ToolINFOID:0000000003531583
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
EG17650301
(J-33984-A)
Radiator cap tester
adapterAdapting radiator cap tester to radiator cap and ra-
diator filler neck
a: 28 (1.10) dia.
b: 31.4 (1.236) dia.
c: 41.3 (1.626) dia.
Unit: mm (in)
KV10117100
(J-36471-A)
Heated oxygen sensor
wrenchLoosening or tightening heated oxygen sensors
with 22 mm (0.87 in) hexagon nut
KV10114400
(J-38365)
Heated oxygen sensor
wrenchLoosening or tightening heated oxygen sensors
a: 22 mm (0.87 in)
(J-44626)
Air fuel ratio (A/F) sen-
sor wrenchLoosening or tightening air fuel ratio (A/F) sensor 1
(J-44321)
Fuel pressure gauge
kitChecking fuel pressure
(J-44321-6)
Fuel pressure adapterConnecting fuel pressure gauge to quick connec-
tor type fuel lines.
S-NT564
S-NT379
S-NT636
LEM054
LEC642
LBIA0376E

EC-22
< SERVICE INFORMATION >
PREPARATION
Commercial Service Tool
INFOID:0000000003531584
(J-45488)
Quick connector re-
leaseRemove fuel tube quick connectors in engine
room.
(J-23688)
Engine coolant refrac-
tometerChecking concentration of ethylene glycol in en-
gine coolant Tool number
(Kent-Moore No.)
Tool nameDescription
PBIC0198E
WBIA0539E
Tool name
(Kent-Moore No.)Description
Leak detector
i.e.: (J-41416)Locating the EVAP leak
EVAP service port
adapter
i.e.: (J-41413-OBD)Applying positive pressure through EVAP service
port
Fuel filler cap adapter
i.e.: (MLR-8382)Checking fuel tank vacuum relief valve opening
pressure
Socket wrench Removing and installing engine coolant tempera-
ture sensor
S-NT703
S-NT704
S-NT815
S-NT705

ENGINE CONTROL SYSTEM
EC-25
< SERVICE INFORMATION >
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*1: This sensor is not used to control the engine system. This is used only for the on board diagnosis.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.
• During warm-up
• When starting the engine
• During acceleration
• Hot-engine operation
• When selector lever is changed from N to D
• High-load, high-speed operation

• During deceleration
• During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Knock sensor Engine knocking condition
Battery
Battery voltage*
3
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit)
VDC/TCS operation command*
2
Air conditioner switch
Air conditioner operation*2
Wheel sensor
Vehicle speed*2
PBIB3020E

EC-36
< SERVICE INFORMATION >
EVAPORATIVE EMISSION SYSTEM
Check EVAP canister as follows:
1. Block port B.
2. Blow air into port Aand check that it flows freely out of port C.
3. Release blocked port B.
4. Apply vacuum pressure to port B and check that vacuum pres-
sure exists at the ports Aand C.
5. Block port Aand B.
6. Apply pressure to port C and check that there is no leakage.
FUEL TANK VACUUM RELIEF VALVE (BUILT INTO FUEL FILLER CAP)
1. Wipe clean valve housing.
2. Check valve opening pressure and vacuum.
3. If out of specification, replace fuel filler cap as an assembly.
CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incor-
rect fuel filler cap is used, the MIL may come on.
EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Refer to EC-366and EC-373.
FUEL TANK TEMPERATURE SENSOR
Refer to EC-310and EC-314.
EVAP CANISTER VENT CONTROL VALVE
Refer to EC-379and EC-386.
EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to EC-392, EC-395and EC-401.
EVAP SERVICE PORT
PBIB1212E
SEF445Y
Pressure:
15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2, 2.22 -
2.90 psi)
Vacuum:
−6.0 to −3.3 kPa (−0.061 to −0.034 kg/cm
2,
−0.87 to −0.48 psi)
SEF943S

EVAPORATIVE EMISSION SYSTEM
EC-37
< SERVICE INFORMATION >
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Positive pressure is delivered to the EVAP system through the EVAP
service port. If fuel vapor leakage in the EVAP system occurs, use a
leak detector to locate the leak.
Removal and InstallationINFOID:0000000003531596
EVAP CANISTER
Tighten EVAP canister as shown in the figure.
EVAP CANISTER VENT CONTROL VALVE
1. Turn EVAP canister vent control valve counterclockwise.
2. Remove the EVAP canister vent control valve.
Always replace O-ring with a new one.
How to Detect Fuel Vapor LeakageINFOID:0000000003531597
CAUTION:
• Never use compressed air or a high pressure pump.
• Do not exceed 4.12 kPa (0.042 kg/cm
2, 0.6 psi) of pressure in EVAP system.
NOTE:
• Do not start engine.
• Improper installation of EVAP service port adapter to the EVAP service port may cause a leak.
BBIA0366E
: N-·m (kg-m, in-lb)
BBIA0349E
BBIA0350E