2004 INFINITI QX56 stop start

EC-464Revision: August 2007
DTC P1276, P1286 A/F SENSOR 1
2004 QX56
If the indication is constantly approx. 1.5V and does not fluctuates, go to EC-469, "Diagnostic Procedure"
.
If the indication fluctuates around 1.5V, go to next step.
4. Select “A/F SEN1 (B1) P1276” or “A/F SEN1 (B2) P1286” of “A/F SEN1” in “DTC WORK SUPPORT”
mode with CONSULT-II.
5. Touch “START”.
6. When the following conditions are met, “TESTING” will be dis-
played on the CONSULT-II screen.
If “TESTING” is not displayed after 20 seconds, retry from
step 2.
7. Release accelerator pedal fully.
NOTE:
Never apply brake during releasing the accelerator pedal.
8. Make sure that “TESTING” changes to “COMPLETED”.
If “TESTING” changed to “OUT OF CONDITION”, retry from
step 6.
9. Make sure that “OK” is displayed after touching “SELF-DIAG
RESULT”.
If “NG” is displayed, go to EC-469, "
Diagnostic Procedure" .
Overall Function CheckUBS00HAB
Use this procedure to check the overall function of the A/F sensor 1 circuit. During this check, a 1st trip DTC
might not be confirmed.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in the suitable gear position.
3. Set 5th position, then release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30
MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
4. Repeat steps 2 to 3 five times.
5. Stop the vehicle and turn ignition switch OFF.
6. Wait at least 10 seconds and restart engine.
ENG SPEED 850 - 3,200 rpm
Vehicle speed More than 64 km/h (40 MPH)
B/FUEL SCHDL 1.0 - 8.0 msec
Selector lever D position with “OD” ON
SEF 5 76 Z
SEF 5 77 Z
SEF 5 78 Z

EC-480Revision: August 2007
DTC P1278, P1288 A/F SENSOR 1
2004 QX56
5. CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching “CLEAR”
or “START”.
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P172, P0174 or P0175 detected?
Is it difficult to start engine?
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con-
nector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-62, "
HOW TO ERASE
EMISSION-RELATED DIAGNOSTIC INFORMATION" .
8. Make sure DTC P0000 is displayed.
9. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-208 or EC-217
.
No >> GO TO 6.
SEF 9 68 Y
BBIA0368E

EC-492Revision: August 2007
DTC P1279, P1289 A/F SENSOR 1
2004 QX56
5. CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching “CLEAR”
or “START”.
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P172, P0174 or P0175 detected?
Is it difficult to start engine?
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con-
nector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-62, "
HOW TO ERASE
EMISSION-RELATED DIAGNOSTIC INFORMATION" .
8. Make sure DTC P0000 is displayed.
9. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-208 or EC-217
.
No >> GO TO 6.
SEF 9 68 Y
BBIA0368E

DTC P1572 ICC BRAKE SWITCH
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Revision: August 20072004 QX56
DTC P1572 ICC BRAKE SWITCHPFP:25320
Component DescriptionUBS00HYZ
When the brake pedal is depressed, ICC brake switch is turned OFF
and stop lamp switch is turned ON. ECM detects the state of the
brake pedal by this input of two kinds (ON/OFF signal).
Refer to ACS-6, "
DESCRIPTION" for the ICC function.
CONSULT-II Reference Value in Data Monitor ModeUBS00HZ0
Specification data are reference values.
On Board Diagnosis LogicUBS00HZ1
NOTE:

If DTC P1572 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-351, "
DTC P0605 ECM" .

This diagnosis has the one trip detection logic.

The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureUBS00HZ2
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Steps 3 and 4 may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a
road test is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-II
1. Start engine.
BBIA0470E
MONITOR ITEM CONDITION SPECIFICATION
BRAKE SW1
(ICC brake switch)

Ignition switch: ON
Brake pedal: Fully released ON

Brake pedal: Slightly depressed OFF
BRAKE SW2
(stop lamp switch)

Ignition switch: ON
Brake pedal: Fully released OFF

Brake pedal: Slightly depressed ON
DTC No. Trouble Diagnosis Name DTC Detecting Condition Possible Cause
P1572
1572ICC brake switchON signals from the stop lamp switch and the
ICC brake switch are sent to ECM at the same
time.

Harness or connectors
(The stop lamp switch circuit is open or
shorted.)

Harness or connectors
(The ICC brake switch circuit is open or
shorted.)

Stop lamp switch

ICC brake switch

ICC brake hold relay

Incorrect stop lamp switch installation

Incorrect ICC brake switch installation

ECM

FUEL PUMP CIRCUIT
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Revision: August 20072004 QX56
FUEL PUMP CIRCUITPFP:17042
DescriptionUBS00HDB
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signals of engine speed and battery voltage.
The ECM activates the fuel pump for several seconds after the ignition switch is turned ON to improve engine
startability. If the ECM receives a engine speed signal from the camshaft position sensor (PHASE), it knows
that the engine is rotating, and causes the pump to operate. If the engine speed signal is not received when
the ignition switch is ON, the engine stalls. The ECM stops pump operation and prevents battery discharging,
thereby improving safety. The ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump
relay, which in turn controls the fuel pump.
COMPONENT DESCRIPTION
A turbine type design fuel pump is used in the furl tank.
CONSULT-II Reference Value in Data Monitor ModeUBS00HDC
Specification data are reference values.
Sensor Input signal to ECM ECM Function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
Fuel pump control Fuel pump relay
Battery Battery voltage*
Condition Fuel pump operation
Ignition switch is turned to ON. Operates for 1 second.
Engine running and crankingOperates.
When engine is stoppedStops in 1.5 seconds.
Except as shown aboveSto ps.
BBIA0402E
MONITOR ITEM CONDITION SPECIFICATION
FUEL PUMP RLY

For 1 second after turning ignition switch ON

Engine running or crankingON

Except above conditions OFF

SQUEAK AND RATTLE TROUBLE DIAGNOSIS
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Revision: August 20072004 QX56
73982-9E000: 45 mm (1.77 in) thick, 50 x 50 mm (1.97 x 1.97 in)/73982-50Y00: 10 mm (0.39 in) thick, 50 x 50
mm (1.97 x 1.97 in)
INSULATOR (Light foam block)
80845-71L00: 30 mm (1.18 in) thick, 30 x 50 mm (1.18 x 1.97 in)
FELT CLOTH TAPE
Used to insulate where movement does not occur. Ideal for instrument panel applications.
68370-4B000: 15 x 25 mm (0.59 x 0.98 in) pad/68239-13E00: 5 mm (0.20 in) wide tape roll
The following materials, not found in the kit, can also be used to repair squeaks and rattles.
UHMW (TEFLON) TAPE
Insulates where slight movement is present. Ideal for instrument panel applications.
SILICONE GREASE
Used in place of UHMW tape that will be visible or not fit.
Note: Will only last a few months.
SILICONE SPRAY
Use when grease cannot be applied.
DUCT TAPE
Use to eliminate movement.
CONFIRM THE REPAIR
Confirm that the cause of a noise is repaired by test driving the vehicle. Operate the vehicle under the same
conditions as when the noise originally occurred. Refer to the notes on the Diagnostic Worksheet.
Generic Squeak and Rattle TroubleshootingEIS0063B
Refer to Table of Contents for specific component removal and installation information.
INSTRUMENT PANEL
Most incidents are caused by contact and movement between:
1. The cluster lid A and instrument panel
2. Acrylic lens and combination meter housing
3. Instrument panel to front pillar garnish
4. Instrument panel to windshield
5. Instrument panel mounting pins
6. Wiring harnesses behind the combination meter
7. A/C defroster duct and duct joint
These incidents can usually be located by tapping or moving the components to duplicate the noise or by
pressing on the components while driving to stop the noise. Most of these incidents can be repaired by apply-
ing felt cloth tape or silicone spray (in hard to reach areas). Urethane pads can be used to insulate wiring har-
ness.
CAUTION:
Do not use silicone spray to isolate a squeak or rattle. If you saturate the area with silicone, you will
not be able to recheck the repair.
CENTER CONSOLE
Components to pay attention to include:
1. Shifter assembly cover to finisher
2. A/C control unit and cluster lid C
3. Wiring harnesses behind audio and A/C control unit
The instrument panel repair and isolation procedures also apply to the center console.
DOORS
Pay attention to the:
1. Finisher and inner panel making a slapping noise
2. Inside handle escutcheon to door finisher
3. Wiring harnesses tapping
4. Door striker out of alignment causing a popping noise on starts and stops

PRECAUTIONS
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Revision: August 20072004 QX56
PRECAUTIONSPFP:00001
Precautions for Drain Engine CoolantEBS00IKY
Drain engine coolant when engine is cooled.
Precautions for Disconnecting Fuel PipingEBS00IKZ

Before starting work, make sure no fire or spark producing items are in the work area.

Release fuel pressure before disconnecting and disassembly.

After disconnecting pipes, plug openings to stop fuel leakage.
Precautions for Removal and DisassemblyEBS00IL0

When instructed to use special service tools, use the specified tools. Always be careful to work safely,
avoid forceful or uninstructed operations.

Exercise maximum care to avoid damage to mating or sliding surfaces.

Cover openings of engine system with tape or the equivalent, if necessary, to seal out foreign materials.

Mark and arrange disassembly parts in an organized way for easy troubleshooting and assembly.

When loosening nuts and bolts, as a basic rule, start with the one furthest outside, then the one diagonally
opposite, and so on. If the order of loosening is specified, do exactly as specified. Power tools may be
used where noted in the step.
Precautions for Inspection, Repair and ReplacementEBS00IL1
Before repairing or replacing, thoroughly inspect parts. Inspect new replacement parts in the same way, and
replace if necessary.
Precautions for Assembly and InstallationEBS00IL2

Use torque wrench to tighten bolts or nuts to specification.

When tightening nuts and bolts, as a basic rule, equally tighten in several different steps starting with the
ones in center, then ones on inside and outside diagonally in this order. If the order of tightening is speci-
fied, do exactly as specified.

Replace with new gasket, packing, oil seal or O-ring.

Thoroughly wash, clean, and air-blow each part. Carefully check engine oil or engine coolant passages for
any restriction and blockage.

Avoid damaging sliding or mating surfaces. Completely remove foreign materials such as cloth lint or dust.
Before assembly, oil sliding surfaces well.

Release air within route when refilling after draining engine coolant.

Before starting engine, apply fuel pressure to fuel lines with turning ignition switch ON (with engine
stopped). Then make sure that there are no leaks at fuel line connections.

After repairing, start engine and increase engine speed to check engine coolant, fuel, oil, and exhaust
systems for leakage.
Parts Requiring Angular TighteningEBS00IL3

For final tightening of the following engine parts use Tool:
–Cylinder head bolts
–Main bearing cap bolts
–Connecting rod cap bolts
–Crankshaft pulley bolt (No angle wrench is required as the bolt flange is provided with notches for angle
tightening)

Do not use a torque value for final tightening.

The torque value for these parts are for a preliminary step.

Ensure thread and seat surfaces are clean and lightly coated with engine oil. Tool number : KV10112100 (BT-8653-A)

EM-18Revision: August 2007
INTAKE MANIFOLD
2004 QX56
5. Install the quick connector cap on the quick connector joint (on
engine side only).
6. Install the fuel hose and tube to hose clamps.
7. Refill the engine coolant. Refer to MA-13, "
REFILLING ENGINE
COOLANT" .
INSPECTION AFTER INSTALLATION

After installing fuel tubes, make sure there is no fuel leakage at connections in the following steps.
–Apply fuel pressure to fuel lines with turning ignition switch ON (with engine stopped). Then check for
fuel leaks at connections.
–Start the engine and rev it up and check for fuel leaks at connections.

Perform procedures for “Throttle Valve Closed Position Learning” after finishing repairs. Refer to EC-44,
"Throttle Valve Closed Position Learning" .

If electric throttle control actuator is replaced, perform procedures for “Idle Air Volume Learning” after fin-
ishing repairs. Refer to EC-44, "
Idle Air Volume Learning" .
SBIA0354E