2004 INFINITI QX56 fuel pressure

GI-6
PRECAUTIONS
Revision: August 20072004 QX56
(i.e. Flexible Fuel Vehicle - FFV models). Using a fuel other than that specified could adversely affect
the emission control devices and systems, and could also affect the warranty coverage validity.
Precautions for Multiport Fuel Injection System or Engine Control SystemEAS0014B

Before connecting or disconnecting any harness connector for
the multiport fuel injection system or ECM:
Turn ignition switch to “OFF” position.
Disconnect negative battery terminal.
Otherwise, there may be damage to ECM.

Before disconnecting pressurized fuel line from fuel pump to
injectors, be sure to release fuel pressure.

Be careful not to jar components such as ECM and mass air
flow sensor.
Precautions for HosesEAS0014C
HOSE REMOVAL AND INSTALLATION

To prevent damage to rubber hose, do not pry off rubber hose
with tapered tool or screwdriver.

To reinstall the rubber hose securely, make sure of hose inser-
tion length and clamp orientation. (If tube is equipped with hose
stopper, insert rubber hose into tube until it butts up against
hose stopper.)
HOSE CLAMPING

If old rubber hose is re-used, install hose clamp in its original
position (at the indentation where the old clamp was). If there is
a trace of tube bulging left on the old rubber hose, align rubber
hose at that position.

Discard old clamps; replace with new ones.
SGI787
SM A01 9D
SM A02 0D
SM A02 1D

GI-50
TERMINOLOGY
Revision: August 20072004 QX56
TERMINOLOGYPFP:00011
SAE J1930 Terminology List EAS00157
All emission related terms used in this publication in accordance with SAE J1930 are listed. Accordingly, new
terms, new acronyms/abbreviations and old terms are listed in the following chart.
NEW TERMNEW ACRONYM /
ABBREVIATIONOLD TERM
Air cleaner ACL Air cleaner
Barometric pressure BARO ***
Barometric pressure sensor-BCDD BAROS-BCDD BCDD
Camshaft position CMP ***
Camshaft position sensor CMPS Crank angle sensor
Canister *** Canister
Carburetor CARB Carburetor
Charge air cooler CAC Intercooler
Closed loop CL Closed loop
Closed throttle position switch CTP switch Idle switch
Clutch pedal position switch CPP switch Clutch switch
Continuous fuel injection system CFI system ***
Continuous trap oxidizer system CTOX system ***
Crankshaft position CKP ***
Crankshaft position sensor CKPS ***
Data link connector DLC ***
Data link connector for CONSULT-II DLC for CONSULT-II Diagnostic connector for CONSULT-II
Diagnostic test mode DTM Diagnostic mode
Diagnostic test mode selector DTM selector Diagnostic mode selector
Diagnostic test mode I DTM I Mode I
Diagnostic test mode II DTM II Mode II
Diagnostic trouble code DTC Malfunction code
Direct fuel injection system DFI system ***
Distributor ignition system DI system Ignition timing control
Early fuel evaporation-mixture heater EFE-mixture heater Mixture heater
Early fuel evaporation system EFE system Mixture heater control
Electrically erasable programmable read
only memoryEEPROM ***
Electronic ignition system EI system Ignition timing control
Engine control EC ***
Engine control module ECM ECCS control unit
Engine coolant temperature ECT Engine temperature
Engine coolant temperature sensor ECTS Engine temperature sensor
Engine modification EM ***
Engine speed RPM Engine speed
Erasable programmable read only memory EPROM ***
Evaporative emission canister EVAP canister Canister
Evaporative emission system EVAP system Canister control solenoid valve
Exhaust gas recirculation valve EGR valve EGR valve

TERMINOLOGY
GI-51
C
D
E
F
G
H
I
J
K
L
MB
GI
Revision: August 20072004 QX56
Exhaust gas recirculation control-BPT
valveEGRC-BPT valve BPT valve
Exhaust gas recirculation control-solenoid
valveEGRC-solenoid valve EGR control solenoid valve
Exhaust gas recirculation temperature sen-
sor
EGRT sensor Exhaust gas temperature sensor
EGR temperature sensor
Flash electrically erasable programmable
read only memoryFEEPROM ***
Flash erasable programmable read only
memoryFEPROM ***
Flexible fuel sensor FFS ***
Flexible fuel system FF system ***
Fuel pressure regulator *** Pressure regulator
Fuel pressure regulator control solenoid
valve*** PRVR control solenoid valve
Fuel trim FT ***
Heated Oxygen sensor HO2S Exhaust gas sensor
Idle air control system IAC system Idle speed control
Idle air control valve-air regulator IACV-air regulator Air regulator
Idle air control valve-auxiliary air control
valveIACV-AAC valve Auxiliary air control (AAC) valve
Idle air control valve-FICD solenoid valve IACV-FICD solenoid valve FICD solenoid valve
Idle air control valve-idle up control sole-
noid valveIACV-idle up control solenoid valve Idle up control solenoid valve
Idle speed control-FI pot ISC-FI pot FI pot
Idle speed control system ISC system ***
Ignition control IC ***
Ignition control module ICM ***
Indirect fuel injection system IFI system ***
Intake air IA Air
Intake air temperature sensor IAT sensor Air temperature sensor
Knock *** Detonation
Knock sensor KS Detonation sensor
Malfunction indicator lamp MIL Check engine light
Manifold absolute pressure MAP ***
Manifold absolute pressure sensor MAPS ***
Manifold differential pressure MDP ***
Manifold differential pressure sensor MDPS ***
Manifold surface temperature MST ***
Manifold surface temperature sensor MSTS ***
Manifold vacuum zone MVZ ***
Manifold vacuum zone sensor MVZS ***
Mass air flow sensor MAFS Air flow meter
Mixture control solenoid valve MC solenoid valve Air-fuel ratio control solenoid valve
Multiport fuel injection System MFI system Fuel injection controlNEW TERMNEW ACRONYM /
ABBREVIATIONOLD TERM

IDX-4
ALPHABETICAL INDEX
Driver air bag .................................................. SRS-45
DTC work support ............................................ EC-113
DTRL - Wiring diagram ....................................... LT-37
Duct and grilles .............................................. ATC-157
DVD Player ........................................................ AV-59
E
ECM input/output signal ..................................... EC-96
ECM power supply ............................. EC-128, EC-361
ECM relay ........................................................ EC-128
ECM/PW - Wiring diagram ............................... EC-362
ECTS - Wiring diagram .................................... EC-167
Electric sunroof .................................................. RF-10
Electric throttle control actuator ......... EC-365, EC-367
Electrical load signal circuit .............................. EC-612
Electrical units location ...................................... PG-64
Electronic ignition (EI) system ........................... EC-28
Engine control circuit diagram ........................... EC-94
Engine control component parts location ........... EC-88
Engine control module (ECM) .......................... EC-351
Engine control system diagram and chart ......... EC-23
Engine coolant .................................................... CO-8
Engine coolant temperature sensor (ECTS) ... EC-165,
EC-178
Engine fail-safe system ...................................... EC-77
Engine oil ............................................................. LU-7
Engine oil filter replacement ............................. MA-16
Engine oil precautions .......................................... GI-7
Engine oil replacement ..................................... MA-16
Engine removal ................................................. EM-70
Engine room cover ............................................ EM-11
Engine serial number .......................................... GI-48
ETC1 - Wiring diagram .................................... EC-368
ETC2 - Wiring diagram .................................... EC-375
ETC3 - Wiring diagram .................................... EC-379
EVAP canister .................................................. EC-636
EVAP canister purge volume control solenoid valve ....
EC-285
, EC-496
EVAP canister vent control valve ....... EC-292, EC-504
EVAP control system (small leak) diagnosis .. EC-276,
EC-316
, EC-324
EVAP control system pressure sensor .... EC-299, EC-
302, EC-308
EVAP control system purge flow monitoring diagnosis
EC-271
EVAP vapor lines inspection ............................. MA-19
Evaporative emission (EVAP) system ............. EC-633
Evaporator ..................................................... ATC-175
Exhaust manifold .............................................. EM-19
Exhaust system ................................................... EX-3
Exhaust system inspection .................................. EX-3
Expansion valve ............................................. ATC-177
F
F/FOG - Wiring diagram ..................................... LT-71
F/PUMP - Wiring diagram ................................ EC-602
Final drive pre-inspection .................. FFD-15, RFD-12
Final drive removal and installation ... FFD-12, RFD-10
Flow charts .......................................................... GI-27
Fluid temperature sensor (A/T) ........................ AT-131
Fluids ................................................................ MA-10
Fluorescent leak detector .............................. ATC-178
Fog lamp, front ................................................... LT-69
Foot lamp ......................................................... LT-129
Freeze frame data ............................... EC-54, EC-107
Front brake solenoid valve ................. AT-151, AT-154
Front bumper ...................................................... EI-13
Front case (Transfer) ....................................... TF-125
Front combination lamp removal and installation LT-33
Front door ............................. BL-129, BL-132, GW-69
Front Door Trim ................................................... EI-31
Front drive shaft (Transfer) .............................. TF-115
Front fog lamp .................................................... LT-69
Front passenger air bag .................................. SRS-50
Front seat ........................................................... SE-96
Front seat belt ...................................................... SB-3
Front seat belt pre-tensioner ............... SRS-3, SRS-57
Front washer ...................................................... WW-4
Front wiper ......................................................... WW-4
FTTS - Wiring diagram ...................... EC-227, EC-232
Fuel cut control (at no load high engine speed) EC-30
Fuel filter replacement ......................................... FL-5
Fuel gauge ............................................................ DI-5
Fuel injection system (Bank 1) .......... EC-208, EC-217
Fuel injection system (Bank 2) .......... EC-208, EC-217
Fuel injector and fuel tube ................................. EM-29
Fuel level sensor ................. EC-334, EC-336, EC-338
Fuel line inspection .............................................. FL-3
Fuel precautions ................................................... GI-5
Fuel pressure check .......................................... EC-46
Fuel pressure release ....................................... EC-46
Fuel pump ....................................................... EC-601
Fuel pump and gauge .......................................... FL-5
Fuel system .......................................................... FL-3
Fuel tank .............................................................. FL-9
Fuel tank temperature sensor ........... EC-225, EC-231
Fuel tank vacuum relief valve ......................... EC-636
FUELB1 - Wiring diagram ................. EC-210, EC-219
FUELB2 - Wiring diagram ................. EC-211, EC-220
Fuse ...................................................... PG-67, PG-77
Fuse and fusible link box .................................. PG-77
Fuse block ......................................................... PG-76
Fusible link ............................................ PG-67, PG-77
G
Garage jack and safety stand ............................. GI-40
Gauges ................................................................. DI-5
Generator .......................................................... SC-17
Generic scan tool (GST) ................................. EC-116
Glass ...................................... GW-11, GW-69, GW-72
Glove box lamp ................................... LT-152, LT-153
GPS antenna ..................................................... AV-62
Grease .............................................................. MA-10
Ground distribution ............................................ PG-30

IDX-6
ALPHABETICAL INDEX
M
MAFS - Wiring diagram ..................... EC-149
, EC-156
Magnet clutch ............................... ATC-104, ATC-167
MAIN - Wiring diagram .................................... EC-128
Main oil pump (Transfer) .................................. TF-122
Mainshaft (Transfer) ........................................ TF-116
Maintenance (engine)Schedule 1 ....................... MA-6
Maintenance (engine)Schedule 2 ....................... MA-8
Major overhaul (Final drive) .............. FFD-14, RFD-13
Major overhaul (Transfer) ................................ TF-110
Malfunction indicator lamp (MIL) ........................ EC-63
Map lamp .......................................................... LT-129
Mass air flow sensor (MAFS) ............. EC-146, EC-154
Meter ..................................................................... DI-5
METER - Wiring diagram .................................... DI-10
MIL data link connectors circuit ....................... EC-631
MIL/DL - Wiring diagram .................................. EC-631
MIRROR - Wiring diagram ................................ GW-99
Misfire .............................................................. EC-243
Mode door control linkage adjustment ............. ATC-65
Mode door motor ............................ ATC-63, ATC-152
Model variation ................................................... GI-46
Multiport fuel injection (MFI) system .................. EC-26
Multiport fuel injection precautions ....................... GI-6
Multi-remote control system ............................... BL-44
N
NATS - Wiring diagram .................................... BL-141
NAVI - Wiring diagram ....................................... AV-79
NAVI Control Unit ............................................ AV-157
Neutral-4LO switch ............................................ TF-96
Nissan torque demand (NTD) control system .... EC-29
NVH troubleshooting (AX) ................................. FAX-4
NVH troubleshooting (EM) .................................. EM-9
NVH troubleshooting (Final drive) ..................... RFD-5
NVH troubleshooting (Propeller shaft) ................. PR-3
NVH troubleshooting (RAX) .............................. RAX-4
NVH troubleshooting (RSU) .............................. RSU-5
NVH troubleshooting (ST) .................................... PS-5
NVH troubleshooting (WT)NVH troubleshooting (WT) .
WT-3
NVIS (Nissan vehicle immobilizer system) precautions
GI-3
O
O2H2B1 - Wiring diagram ................................ EC-140
O2H2B2 - Wiring diagram ................................ EC-142
O2S2B1 - Wiring diagram .. EC-188, EC-199, EC-386,
EC-398
O2S2B2 - Wiring diagram .. EC-190, EC-201, EC-388,
EC-400
Oil cooler (engine) ............................................. LU-11
Oil filter ............................................................... LU-10
Oil filter (Transfer) ............................................ TF-107
Oil pan (engine) ................................................ EM-22
Oil pressure (engine) ........................................... LU-7
Oil pressure relief valve (engine) ......................... LU-5
Oil pump (engine) .............................................. LU-13
Oil seal replacement (engine) ........................... EM-56
Oil seal replacement (front of final drive) FFD-8, RFD-6
Oil seal replacement (side of final drive) FFD-10, RFD-
8
On board diagnostic system ............................. EC-49
ORVR (On-board Refueling Vapor Recovery) EC-640
Overheat ......................................................... EC-410
P
P/SCKT - Wiring diagram ................................. WW-54
Pantograph jack .................................................. GI-40
Park/Neutral position switch ............................ EC-546
Park/neutral position switch (A/T) .................... AT-109
Parking brake control ........................................... PB-4
Parking lamp .................................................... LT-108
PCV (positive crankcase ventilation) .............. EC-645
Periodic maintenance ......................................... MA-6
Personal lamp .................................................. LT-129
PGC/V - Wiring diagram ................... EC-287, EC-498
PHASE - Wiring diagram ................................ EC-261
Pinion bearing preload diff. ............................. RFD-21
Piston pin inspection ......................................... EM-89
Piston ring inspection ........................................ EM-90
Piston to bore clearance ................................... EM-94
Planetary carrier (Transfer) .............................. TF-127
PNP/SW - Wiring diagram .............................. EC-548
POS - Wiring diagram ..................................... EC-256
POWER - Wiring diagram ................................... PG-6
Power seat ......................................................... SE-88
Power steering fluid level .................................. MA-29
Power steering gear ........................................... PS-15
Power steering oil pump .................................... PS-26
Power steering pressure (PSP) sensor ........... EC-346
Power steering system bleeding .......................... PS-6
Power supply routing .......................................... PG-4
Power window .................................................. GW-15
PRE/SE - Wiring diagram ................. EC-304, EC-310
Precautions (General) ........................................... GI-4
Precautions in repairing high strength steel ..... BL-192
Pressure switch 1 ............................... AT-154, AT-175
Pressure switch 2 ............................................. AT-172
Pressure switch 3 ............................... AT-148, AT-178
Pressure switch 5 ............................... AT-160, AT-181
Pressure switch 6 ............................... AT-166, AT-184
Pressure test (A/T) ............................................. AT-59
Propeller shaft ........................................... PR-4, PR-8
Propeller shaft inspection .................................. MA-24
Propeller shaft on vehicle service ....................... PR-8
Propeller shaft vibration ............................ PR-4, PR-8
PS/SEN - Wiring diagram ............................... EC-347
R
R/VIEW - Wiring diagram .................................... DI-75
Radiator ............................................................ CO-10
Rear Audio Remote Control Unit ....................... AV-47

LAN-12
[CAN]
CAN COMMUNICATION
Revision: August 20072004 QX56
Buzzer output signal R T
Fuel level sensor signal R T
ASCD SET lamp signal T R
ASCD CRUISE lamp signal T R
Malfunction indicator lamp signal T R
Fuel level low warning signal T R
Front wiper request signal T R
Front wiper stop position signal R T
Rear window defogger switch signal T R R
Rear window defogger control signal R R R T
Hood switch signal R T
Theft warning horn request signal T R
Horn chirp signal T R
Steering angle sensor signal T R
ABS warning lamp signal R T
VDC OFF indicator lamp signal R T
SLIP indicator lamp signal R T
Brake warning lamp signal R T
System setting signalRT
TR
Distance to empty signal T R
ASCD operation signal T R
ASCD OD cancel request T R
A/T CHECK indicator lamp signal T R
A/T position indicator lamp signal T R R
Tire pressure signal R T
Tire pressure data signal R T
1st position switch signal R T
4th position switch signal R T
Tow mode switch signal R T
A/T fluid temperature sensor signal T RSignals ECM TCMDriver
seat
con-
trol
unitCom-
bina-
tion
meterDis-
play
con-
trol
unitBCMSteer-
ing
angle
sen-
sorFront
air
con-
trolTrans-
fer
con-
trol
unitABS
actua-
tor
and
elec-
tric
unit
(con-
trol
unit)IPDM
E/R

HEADLAMP (FOR USA)
LT-31
C
D
E
F
G
H
I
J
L
MA
B
LT
Revision: August 20072004 QX56
Aiming AdjustmentEKS007A6
For details, refer to the regulations in your state.
Before performing aiming adjustment, check the following.
1. Ensure all tires are inflated to correct pressure.
2. Place vehicle and screen on level surface.
3. Ensure there is no load in vehicle other than the driver (or equivalent weight placed in driver's position).
Coolant and engine oil filled to correct level, and fuel tank full.
4. Confirm spare tire, jack and tools are properly stowed.
5. Confirm headlamp aiming switch is set to "0" (zero) position.
LOW BEAM AND HIGH BEAM
NOTE:
Aim each headlamp individually and ensure other headlamp beam pattern is blocked from screen.
1. Turn headlamp low beam on.
2. Use adjusting screw to perform aiming adjustment.
WKIA1859E

LT-78
FRONT FOG LAMP
Revision: August 20072004 QX56
Aiming AdjustmentEKS007BF
The fog lamp is a semi-sealed beam type which uses a replaceable halogen bulb. Before performing aiming
adjustment, make sure of the following.

Keep all tires inflated to correct pressure.

Place vehicle on level ground.

See that vehicle is unloaded (except for full levels of coolant,
engine oil and fuel, and spare tire, jack, and tools). Have the
driver or equivalent weight placed in driver seat.
Adjust aiming in the vertical direction by turning the adjustment
screw.
NOTE:
Access adjustment screw from underneath front bumper. Turn screw
clockwise to raise pattern and counterclockwise to lower pattern.
1. Set the distance between the screen and the center of the fog
lamp lens as shown.
2. Turn front fog lamps ON.
3. Adjust front fog lamps using adjusting screw so that the top edge
of the high intensity zone is 200 mm (7.9 in) below the height of
the fog lamp centers as shown.

When performing adjustment, if necessary, cover the headlamps
and opposite fog lamp.
SEL350X
MEL327G
MEL328GA