2006 INFINITI QX56 check engine light

EC-74Revision: November 2009
BASIC SERVICE PROCEDURE
2006 QX56
10. CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light. Refer to EC-76, "
IGNITION TIMING" .
OK or NG
OK >> GO TO 19.
NG >> GO TO 11.
11 . PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-78, "
Accelerator Pedal Released Position Learning" .
>> GO TO 12.
12. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-78, "
Throttle Valve Closed Position Learning" .
>> GO TO 13.
13. PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-78, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 14.
No >> 1. Follow the instruction of Idle Air Volume Learning.
2. GO TO 4.
14. CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-II.
Refer to EC-76, "
IDLE SPEED" .
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. Refer to EC-76, "
IDLE SPEED" .
OK or NG
OK >> GO TO 15.
NG >> GO TO 17. 15
± 5 ° BTDC (in P or N position)
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650 ± 50 rpm (in P or N position)
650 ± 50 rpm (in P or N position)

BASIC SERVICE PROCEDUREEC-75
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15. CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light. Refer to EC-76, "
IGNITION TIMING" .
OK or NG
OK >> GO TO 19.
NG >> GO TO 16.
16. CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-37, "
TIMING CHAIN" .
OK or NG
OK >> GO TO 17.
NG >> 1. Repair the timing chain installation. 2. GO TO 4.
17. DETECT MALFUNCTIONING PART
Check the following.

Check camshaft position sensor (PHASE) and circuit. Refer to EC-347, "DTC P0340 CMP SENSOR
(PHASE)" .

Check crankshaft position sensor (POS) and circuit. Refer to EC-340, "DTC P0335 CKP SENSOR (POS)"
.
OK or NG
OK >> GO TO 18.
NG >> 1. Repair or replace. 2. GO TO 4.
18. CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but this is a rare case.)
2. Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to BL-139, "
ECM Re-communicating Function" .
>> GO TO 4.
19. INSPECTION END
Did you replace ECM, referring this Basic Inspection procedure?
Ye s o r N o
Ye s > > 1 . P e r f o r m EC-77, "VIN Registration" .
2. INSPECTION END
No >> INSPECTION END
15
± 5 ° BTDC (in P or N position)
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BASIC SERVICE PROCEDUREEC-77
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Revision: November 2009 2006 QX56
2. Connect ignition coil No.1 and spark plug with suitable high-ten-
sion wire as shown, and attach timing light clamp to this wire.
3. Check ignition timing.
VIN RegistrationUBS00KZX
DESCRIPTION
VIN Registration is an operation to registering VIN in ECM. It must be performed each time ECM is replaced.
NOTE:
Accurate VIN which is registered in ECM may be required for Inspection & Maintenance (I/M).
OPERATION PROCEDURE With CONSULT-II
1. Check the VIN of the vehicle and note it. Refer to GI-47, "IDENTIFICATION INFORMATION" .
2. Turn ignition switch ON and engine stopped.
3. Select “VIN REGISTRATION ” in “WORK SUPPORT ” mode.
4. Follow the instruction of CONSULT-II display.
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EC-78Revision: November 2009
BASIC SERVICE PROCEDURE
2006 QX56
Accelerator Pedal Released Position LearningUBS00KZY
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time
harness connector of accelerator pedal position sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF and wait at least 10 seconds.
Throttle Valve Closed Position LearningUBS00KZZ
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to learn the fully closed position of the throttle valve by
monitoring the throttle position sensor output signal. It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF wait at least 10 seconds.Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningUBS00L00
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific
range. It must be performed under any of the following conditions:

Each time electric throttle control actuator or ECM is replaced.

Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.

Battery voltage: More than 12.9V (At idle)

Engine coolant temperature: 70 - 100 °C (158 - 212 °F)

Park/Neutral position (PNP) switch: ON

Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine
is start the headlamp will not be illuminated.

Steering wheel: Neutral (Straight-ahead position)

Vehicle speed: Stopped

Transmission: Warmed-up
–With CONSULT-II: Drive vehicle until “ATF TEMP SE 1 ” in “DATA MONITOR” mode of “A/T” system indi-
cates less than 0.9V.
–Without CONSULT-II: Drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-II
1. Perform EC-78, "Accelerator Pedal Released Position Learning" .
2. Perform EC-78, "
Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.

EC-82Revision: November 2009
BASIC SERVICE PROCEDURE
2006 QX56
FUEL PRESSURE CHECK
CAUTION:

Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.

Be careful not to scratch or get the fuel hose connection area dirty when servicing, so that the
quick connector o-ring maintains sealability.

Use Fuel Pressure Gauge Kit J-44321 and Fuel Pressure Adapter J-44321-6 to check fuel pressure.

Do not perform fuel pressure check with electrical system operating (i.e. lights, rear defog, A/C,
etc.). Fuel pressure gauge may indicate false readings due to varying engine loads and changes in
manifold vacuum.
NOTE:
Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel pres-
sure cannot be completely released because JA60 models do not have fuel return system.
1. Release fuel pressure to zero. Refer to EC-80, "
FUEL PRESSURE RELEASE" .
2. Remove engine cover.
3. Remove fuel hose using Quick Connector Release J-45488. Refer to EM-17, "
INTAKE MANIFOLD" .

Do not twist or kink fuel hose because it is plastic hose.

Do not remove fuel hose from quick connector.

Keep fuel hose connections clean.
4. Install Fuel Pressure Adapter J-44321-6 and Fuel Pressure Gauge (from kit J-44321) as shown in figure.

Do not distort or bend fuel rail tube when installing fuel pres-
sure gauge adapter.

When reconnecting fuel hose, check the original fuel hose for
damage and abnormality.
5. Turn ignition switch ON (reactivate fuel pump), and check for fuel leakage.
6. Start engine and check for fuel leakage.
7. Read the indication of fuel pressure gauge.

During fuel pressure check, check for fuel leakage from fuel
connection every 3 minutes.
8. If result is unsatisfactory, go to next step.
9. Check the following.

Fuel hoses and fuel tubes for clogging

Fuel filter for clogging

Fuel pump

Fuel pressure regulator for clogging
If OK, replace fuel pressure regulator.
If NG, repair or replace.
10. Before disconnecting Fuel Pressure Gauge and Fuel Pressure Adapter J-44321-6, release fuel pressure to zero. Refer to EC-80, "
FUEL PRESSURE RELEASE" .
At idling:
Approximately 350 kPa (3.57 kg/cm
2 , 51 psi)
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TROUBLE DIAGNOSISEC-123
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Revision: November 2009 2006 QX56
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
B/FUEL SCHDL
[msec]×

Base fuel schedule indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.

When engine is running specification
range is indicated.
A/F ALPHA-B1 [%]
A/F ALPHA-B2 [%] ×

The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.
When engine is running specification
range is indicated.

This data also includes the data for
the air-fuel ratio learning control.
Monitored item
[Unit] ECM
INPUT
SIGNALS MAIN
SIGNALS Description
Remarks
TEST ITEMCONDITION JUDGEMENTCHECK ITEM (REMEDY)
FUEL INJEC-
TION

Engine: Return to the original
trouble condition

Change the amount of fuel injec-
tion using CONSULT-II. If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Fuel injector

Air fuel ratio (A/F) sensor 1
IGNITION TIM-
ING

Engine: Return to the original
trouble condition

Timing light: Set

Retard the ignition timing using
CONSULT-II. If trouble symptom disappears, see
CHECK ITEM.

Perform Idle Air Volume Learning.
POWER BAL-
ANCE

Engine: After warming up, idle
the engine.

A/C switch: OFF

Selector lever: P or N

Cut off each injector signal one at
a time using CONSULT-II. Engine runs rough or dies.

Harness and connectors

Compression

Fuel injector

Power transistor

Spark plug

Ignition coil
COOLING FAN*

Ignition switch: ON

Turn the cooling fan HI and OFF
using CONSULT-II. Cooling fan moves and stops.

Harness and connectors

Cooling fan motor

IPDM E/R
ENG COOLANT
TEMP

Engine: Return to the original
trouble condition

Change the engine coolant tem-
perature using CONSULT-II. If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Engine coolant temperature sen-
sor

Fuel injector
FUEL PUMP
RELAY

Ignition switch: ON
(Engine stopped)

Turn the fuel pump relay ON and
OFF using CONSULT-II and lis-
ten to operating sound. Fuel pump relay makes the operat-
ing sound.
Harness and connectors

Fuel pump relay
PURG VOL
CONT/V

Engine: After warming up, run
engine at 1,500 rpm.

Change the EVAP canister purge
volume control solenoid valve
opening percent using CON-
SULT-II. Engine speed changes according to
the opening percent.
Harness and connectors

Solenoid valve

EC-362Revision: November 2009
DTC P0441 EVAP CONTROL SYSTEM
2006 QX56
9. If NG, go to EC-362, "Diagnostic Procedure" .
Diagnostic ProcedureUBS00H4N
1. CHECK EVAP CANISTER
1. Turn ignition switch OFF.
2. Check EVAP canister for cracks.
OK or NG
OK (With CONSULT-II)>>GO TO 2.
OK (Without CONSULT-II)>>GO TO 3.
NG >> Replace EVAP canister.
2. CHECK PURGE FLOW
With CONSULT-II
1. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP ser- vice port and install vacuum gauge. For the location of EVAP service port, refer to EC-33, "
EVAPORATIVE
EMISSION LINE DRAWING" .
2. Start engine and let it idle.
3. Select “PURG VOL CONT/V ” in “ACTIVE TEST” mode with CONSULT-II.
4. Rev engine up to 2,000 rpm.
5. Touch “Qd” and “Qu ” on CONSULT-II screen to adjust “PURG
VOL CONT/V” opening and check vacuum existence.
OK or NG
OK >> GO TO 7.
NG >> GO TO 4.
3. CHECK PURGE FLOW
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP ser- vice port and install vacuum gauge. For the location of EVAP service port, refer to EC-33, "
EVAPORATIVE
EMISSION LINE DRAWING" .
4. Start engine and let it idle. Do not depress accelerator pedal even slightly.
5. Check vacuum gauge indication before 60 seconds passed after starting engine.
6. Revving engine up to 2,000 rpm after 100 seconds passed after starting engine.
OK or NG
OK >> GO TO 7.
NG >> GO TO 4.
PURG VOL CONT/V Vacuum
100% Should exist.
0% Should not exist.
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Vacuum should not exist.
Vacuum should exist.

DTC P0451 EVAP CONTROL SYSTEM PRESSURE SENSOREC-403
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DTC Confirmation ProcedureUBS00H59
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.
WITH CONSULT-II
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
3. Start engine and wait at least 40 seconds. NOTE:
Do not depress accelerator pedal even slightly.
If 1st trip DTC is detected, go to EC-403, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureUBS00H5A
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
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