2004 INFINITI QX56 fuel

EC-12Revision: August 2007
INDEX FOR DTC
2004 QX56
DTC No. IndexUBS00GZ4
NOTE:
If DTC U1000 or U1001 is displayed with other DTC, first perform the trouble diagnosis for DTC U1000,
U1001. Refer to EC-135, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .
×:Applicable —: Not applicable
DTC*
1
Items
(CONSULT-II screen terms)TripMIL lighting
upReference page
CONSULT-II
GST*
2ECM*3
U1000
1000*4CAN COMM CIRCUIT 1×EC-135
U1001
1001*4CAN COMM CIRCUIT 2 —EC-135
P0000 0000NO DTC IS DETECTED.
FURTHER TESTING
MAY BE REQUIRED.———
P0037 0037 HO2S2 HTR (B1) 2×EC-138
P0038 0038 HO2S2 HTR (B1) 2×EC-138
P0057 0057 HO2S2 HTR (B2) 2×EC-138
P0058 0058 HO2S2 HTR (B2) 2×EC-138
P0101 0101 MAF SEN/CIRCUIT 1×EC-146
P0102 0102 MAF SEN/CIRCUIT 1×EC-154
P0103 0103 MAF SEN/CIRCUIT 1×EC-154
P 0 11 2 0 11 2 I AT S E N /C I R C U I T 2×EC-161
P 0 11 3 0 11 3 I AT S E N /C I R C U I T 2×EC-161
P0117 0117 ECT SEN/CIRCUIT 1×EC-165
P0118 0118 ECT SEN/CIRCUIT 1×EC-165
P0122 0122 TP SEN 2/CIRC 1×EC-171
P0123 0123 TP SEN 2/CIRC 1×EC-171
P0125 0125 ECT SENSOR 1×EC-178
P0127 0127 IAT SENSOR 2×EC-181
P0128 0128 THERMSTAT FNCTN 2×EC-184
P0138 0138 HO2S2 (B1) 2×EC-186
P0139 0139 HO2S2 (B1) 2×EC-196
P0158 0158 HO2S2 (B2) 2×EC-186
P0159 0159 HO2S2 (B2) 2×EC-196
P0171 0171 FUEL SYS-LEAN-B1 2×EC-208
P0172 0172 FUEL SYS-RICH-B1 2×EC-217
P0174 0174 FUEL SYS-LEAN-B2 2×EC-208
P0175 0175 FUEL SYS-RICH-B2 2×EC-217
P0181 0181 FTT SENSOR 2×EC-225
P0182 0182 FTT SEN/CIRCUIT 2×EC-231
P0183 0183 FTT SEN/CIRCUIT 2×EC-231
P0222 0222 TP SEN 1/CIRC 1×EC-236
P0223 0223 TP SEN 1/CIRC 1×EC-236
P0300 0300 MULTI CYL MISFIRE 2×EC-243
P0301 0301 CYL 1 MISFIRE 2×EC-243
P0302 0302 CYL 2 MISFIRE 2×EC-243
P0303 0303 CYL 3 MISFIRE 2×EC-243

INDEX FOR DTC
EC-13
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Revision: August 20072004 QX56P0304 0304 CYL 4 MISFIRE 2×EC-243
P0305 0305 CYL 5 MISFIRE 2×EC-243
P0306 0306 CYL 6 MISFIRE 2×EC-243
P0307 0307 CYL 7 MISFIRE 2×EC-243
P0308 0308 CYL 8 MISFIRE 2×EC-243
P0327 0327 KNOCK SEN/CIRC-B1 2 —EC-250
P0328 0328 KNOCK SEN/CIRC-B1 2 —EC-250
P0332 0332 KNOCK SEN/CIRC-B2 2 —EC-250
P0333 0333 KNOCK SEN/CIRC-B2 2 —EC-250
P0335 0335 CKP SEN/CIRCUIT 2×EC-255
P0340 0340 CMP SEN/CIRC-B1 2×EC-261
P0420 0420 TW CATALYST SYS-B1 2×EC-267
P0430 0430 TW CATALYST SYS-B2 2×EC-267
P0441 0441 EVAP PURG FLOW/MON 2×EC-271
P0442 0442 EVAP SMALL LEAK 2×EC-276
P0444 0444 PURG VOLUME CONT/V 2×EC-285
P0445 0445 PURG VOLUME CONT/V 2×EC-285
P0447 0447 VENT CONTROL VALVE 2×EC-292
P0451 0451 EVAP SYS PRES SEN 2×EC-299
P0452 0452 EVAP SYS PRES SEN 2×EC-302
P0453 0453 EVAP SYS PRES SEN 2×EC-308
P0455 0455 EVAP GROSS LEAK 2×EC-316
P0456 0456 EVAP VERY SML LEAK 2×EC-324
P0460 0460 FUEL LEV SEN SLOSH 2×EC-334
P0461 0461 FUEL LEVEL SENSOR 2×EC-336
P0462 0462 FUEL LEVL SEN/CIRC 2×EC-338
P0463 0463 FUEL LEVL SEN/CIRC 2×EC-338
P0500 0500
VEH SPEED SEN/CIRC*52×EC-340
P0506 0506 ISC SYSTEM 2×EC-342
P0507 0507 ISC SYSTEM 2×EC-344
P0550 0550 PW ST P SEN/CIRC 2 —EC-346
P0605 0605 ECM 1 or 2× or —EC-351
P0700 0700 TCM 1×AT- 1 0 8
P0705 0705 PNP SW/CIRC 2×AT- 1 0 9
P0710 0710 ATF TEMP SEN/CIRC 2×AT- 1 3 1
P0720 0720
VEH SPD SEN/CIR AT*52×AT - 11 2
P0740 0740 TCC SOLENOID/CIRC 2×AT - 11 8
P0744 0744 A/T TCC S/V FNCTN 2×AT- 1 2 1
P0745 0745 L/PRESS SOL/CIRC 2×AT- 1 2 4
P1031 1031 A/F SEN1 HTR (B1) 2×EC-354
P1032 1032 A/F SEN1 HTR (B1) 2×EC-354
P1051 1051 A/F SEN1 HTR (B2) 2×EC-354
DTC*1
Items
(CONSULT-II screen terms)TripMIL lighting
upReference page
CONSULT-II
GST*
2ECM*3

EC-16Revision: August 2007
PRECAUTIONS
2004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
UBS00GZ5
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.
WAR NIN G:

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 per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal 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
harness connectors.
On Board Diagnostic (OBD) System of Engine and A/TUBS00GZ6
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-
locking type harness connector. For description and how to disconnect, refer to PG-68, "
HAR-
NESS CONNECTOR" .

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.
PrecautionUBS00GZ7

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
battery 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
disconnect battery ground cable.
SEF 2 89 H

PRECAUTIONS
EC-19
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Revision: August 20072004 QX56

Do not operate fuel pump when there is no fuel in lines.

Tighten fuel hose clamps to the specified torque.

Do not depress accelerator pedal when starting.

Immediately after starting, do not rev up engine unneces-
sarily.

Do not rev up engine just prior to shutdown.

When installing C.B. ham radio or a mobile phone, be sure
to observe the following as it may adversely affect elec-
tronic control systems depending on installation location.
–Keep the antenna as far as possible from the electronic
control units.
–Keep the antenna feeder line more than 20 cm (8 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.
–Adjust the antenna and feeder line so that the standing-
wave radio can be kept smaller.
–Be sure to ground the radio to vehicle body.
Wiring Diagrams and Trouble DiagnosisUBS00GZ8
When you read wiring diagrams, refer to the following:

GI-15, "How to Read Wiring Diagrams"

PG-4, "POWER SUPPLY ROUTING CIRCUIT" for power distribution circuit
When you perform trouble diagnosis, refer to the following:

GI-11, "HOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSES"

GI-27, "How to Perform Efficient Diagnosis for an Electrical Incident"
BBIA0402E
SEF 7 09 Y
SEF 7 08 Y

EC-20Revision: August 2007
PREPARATION
2004 QX56
PREPARATIONPFP:00002
Special Service ToolsUBS00GZ9
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.
(J-45488)
Quick connector re-
leaseRemove fuel tube quick connectors in engine
room.
S-NT564
S-NT379
S-NT636
LEM054
LEC642
LBIA0376E
PBIC0198E

EC-22Revision: August 2007
PREPARATION
2004 QX56
Commercial Service ToolsUBS00GZA
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
Oxygen sensor thread
cleaner
i.e.: (J-43897-18)
(J-43897-12)Reconditioning the exhaust system threads before
installing a new oxygen sensor. Use with anti-
seize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for Zirco-
nia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for Tita-
nia Oxygen Sensor
Anti-seize lubricant
i.e.: (Permatex
TM
133AR or equivalent
meeting MIL specifica-
tion MIL-A-907)Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads.
S-NT703
S-NT704
S-NT815
S-NT705
AEM488
S-NT779

ENGINE CONTROL SYSTEM
EC-25
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Revision: August 20072004 QX56
System ChartUBS00GZD
*1: This sensor is not used to control the engine system. This is used only for the on board diagnosis.
*2: This sensor is not used to control the engine system under normal conditions.
*3: This input signal is sent to the ECM through CAN communication line.
*4: This output signal is sent from the ECM through CAN communication line.Input (Sensor) ECM Function Output (Actuator)

Camshaft position sensor (PHASE)

Crankshaft position sensor (POS)

Mass air flow sensor

Engine coolant temperature sensor

A/F sensor 1

Throttle position sensor

Accelerator pedal position sensor

Park/neutral position (PNP) switch

Intake air temperature sensor

Power steering pressure sensor

Ignition switch

Battery voltage

Knock sensor

Refrigerant pressure sensor

Stop lamp switch

ASCD steering switch

ASCD brake switch

Fuel level sensor*1 *3

EVAP control system pressure sensor

Fuel tank temperature sensor*1

Heated oxygen sensor 2*2

TCM (Transmission control module)*3

ABS actuator and electric unit (control unit)*3

Air conditioner switch*3

Wheel sensor*3

Electrical load signal*3
Fuel injection & mixture ratio control Fuel injector
Electronic ignition system Power transistor
Nissan torque demand control system

Electric throttle control actuator

Fuel injector
Fuel pump control Fuel pump relay
ASCD vehicle speed control Electric throttle control actuator
On board diagnostic system
MIL (On the instrument panel)*
4
A/F sensor 1 heater control A/F sensor 1 heater
Heated oxygen sensor 2 heater control Heated oxygen sensor 2 heater
EVAP canister purge flow controlEVAP canister purge volume control
solenoid valve
Air conditioning cut control
Air conditioner relay*
4
Cooling fan control
Cooling fan relay*4
ON BOARD DIAGNOSIS for EVAP system EVAP canister vent control valve

EC-26Revision: August 2007
ENGINE CONTROL SYSTEM
2004 QX56
Multiport Fuel Injection (MFI) SystemUBS00GZE
INPUT/OUTPUT SIGNAL CHART
*1: This sensor is not used to control the engine system under normal conditions.
*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 (POS), camshaft
position sensor (PHASE) 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
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
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)*
2VDC/TCS operation command
Air conditioner switch*
2Air conditioner operation
Wheel sensor*
2Vehicle speed