2011 INFINITI QX56 engine

EC-138
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DIAGNOSIS AND REPAIR WORKFLOW
needed, drive vehicle under the specific driving pattern. Refer to
EC-157, "SRT Set Driving Pat-
tern".
Diagnostic Work SheetINFOID:0000000006217738
DESCRIPTION
There are many operating conditions that lead to the malfunction of
engine components. A good grasp of such conditions can make trou-
bleshooting faster and more accurate.
In general, each customer feels differently about symptoms. It is
important to fully understand the symptoms or conditions for a cus-
tomer complaint.
Utilize a diagnostic worksheet like the WORKSHEET SAMPLE
below in order to organize all the information for troubleshooting.
Some conditions may cause the MIL to illuminate or blink, and DTC
to be detected. Examples:
 Vehicle ran out of fuel, which caused the engine to misfire.
 Fuel filler cap was left off or incorrectly screwed on, allowing fuel to
evaporate into the atmosphere.
WORKSHEET SAMPLE
SEF907L
MTBL0017
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BASIC INSPECTIONEC-139
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BASIC INSPECTION
Work ProcedureINFOID:0000000006217739
1.INSPECTION START
1. Check service records for any recent repairs that ma y indicate a related malfunction, or a current need for
scheduled maintenance.
2. Open engine hood and check the following:
- Harness connectors for improper connections
- Wiring harness for improper connections, pinches and cut
- Vacuum hoses for splits, kinks and improper connections
- Hoses and ducts for leakage
- Air cleaner clogging
- Gasket
3. Check that electrical or mechanical loads are not applied.
- Headlamp switch is OFF.
- Air conditioner switch is OFF.
- Rear window defogger switch is OFF.
- Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature indicator points to the middle of gauge.
Check that engine stays below 1,000 rpm.
5. Run engine at approximately 2,000 rpm for approximately 2 min- utes under no load.
6. Check that no DTC is displayed with CONSULT-III or GST.
Are any DTCs detected?
YES >> GO TO 2.
NO >> GO TO 3.
2.REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnosis Procedure.
>> GO TO 3
3.CHECK IDLE SPEED
1. Run engine at approximately 2,000 rpm for approximately 2 minutes under no load.
SEF983U
SEF976U
SEF977U
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EC-140
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BASIC INSPECTION
2. Rev engine between 2,000 and 3,000 rpm 2 or 3 times under no
load, then run engine at idle speed for approximately 1 minute.
3. Check idle speed.
For procedure, refer to EC-530, "
Inspection".
For specification, refer to EC-538, "
Idle Speed".
Is the inspection result normal?
YES >> GO TO 10.
NO >> GO TO 4.
4.PERFORM ACCELERATOR PEDAL RE LEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-146, "
Work Procedure".
>> GO TO 5.
5.PERFORM THROTTLE VALVE CL OSED POSITION LEARNING
Perform EC-147, "
Work Procedure".
>> GO TO 6.
6.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-148, "
Work Procedure".
Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 7.
NO >> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.
7.CHECK IDLE SPEED AGAIN
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. For procedure, refer to EC-530, "
Inspection".
For specification, refer to EC-538, "
Idle Speed".
Is the inspection result normal?
YES >> GO TO 10.
NO >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the Following.
 Check camshaft position sensor and circuit. Refer to EC-303, "
DTC Logic".
 Check crankshaft position sensor and circuit. Refer to EC-299, "
DTC Logic".
Is the inspection result normal?
YES >> GO TO 9.
NO >> Repair or replace malfunctioning part. Then GO TO 4.
9.CHECK ECM FUNCTION
1. Substitute with a non-malfunctioning ECM to check EC M function. (ECM may be the cause of the incident,
although this is rare.)
2. Perform initialization of IVIS (NATS) system and regist ration of all IVIS (NATS) ignition key IDs. Refer to
SEC-51, "
ECM : Work Procedure".
>> GO TO 4.
10.CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light. For procedure, refer to EC-531, "
Inspection".
PBIA8513J
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BASIC INSPECTIONEC-141
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For specification, refer to
EC-538, "Ignition Timing".
Is the inspection result normal?
YES >> GO TO 19.
NO >> GO TO 11.
11 .PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-146, "
Work Procedure".
>> GO TO 12.
12.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-147, "
Work Procedure".
>> GO TO 13.
13.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-148, "
Work Procedure".
Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 14.
NO >> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.
14.CHECK IDLE SPEED AGAIN
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. For procedure, refer to EC-530, "
Inspection".
For specification, refer to EC-538, "
Idle Speed".
Is the inspection result normal?
YES >> GO TO 15.
NO >> GO TO 17.
15.CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light. For procedure, refer to EC-531, "
Inspection".
For specification, refer to EC-538, "
Ignition Timing".
Is the inspection result normal?
YES >> GO TO 19.
NO >> GO TO 16.
16.CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-62, "
Removal and Installation".
Is the inspection result normal?
YES >> GO TO 17.
NO >> Repair the timing chain installation. Then GO TO 4.
17.DETECT MALFUNCTIONING PART
Check the following.
 Check camshaft position sensor and circuit. Refer to EC-303, "
DTC Logic".
 Check crankshaft position sensor and circuit. Refer to EC-299, "
DTC Logic".
Is the inspection result normal?
YES >> GO TO 18.
NO >> Repair or replace malfunctioning part. Then GO TO 4.
18.CHECK ECM FUNCTION
1. Substitute with a non-malfunctioning ECM to check EC M function. (ECM may be the cause of the incident,
although this is rare.)
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VIN REGISTRATIONEC-145
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VIN REGISTRATION
DescriptionINFOID:0000000006217744
VIN Registration is an operation to register 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).
Work ProcedureINFOID:0000000006217745
1.CHECK VIN
Check the VIN of the vehicle and note it. Refer to GI-23, "
Information About Identification or Model Code".
>> GO TO 2.
2.PERFORM VIN REGISTRATION
WITH CONSULT-III
1. Turn ignition switch ON with engine stopped.
2. Select “VIN REGISTRATION” in “WORK SUPPORT” mode.
3. Follow the instructions on the CONSULT-III display.
>> END
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THROTTLE VALVE CLOSED POSITION LEARNINGEC-147
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THROTTLE VALVE CLOSED
POSITION LEARNING
DescriptionINFOID:0000000006217748
Throttle Valve Closed Position Learning is a function of ECM to learn the fully closed position of the throttle
valve by monitoring the throttle position sensor output signal. It must be performed each time the harness con-
nector of the electric throttle control actuator or ECM is disconnected or elec tric throttle control actuator inside
is cleaned.
Work ProcedureINFOID:0000000006217749
1.START
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “CLSD THL POS LEARN” in “WORK SUPPORT” mode.
3. Follow the instructions on the CONSULT-III display.
4. Turn ignition switch OFF and wait at least 10 seconds.
Check that throttle valve moves during the above 10 seconds by confirming the operating sound.
WITHOUT CONSULT-III
1. Start the engine.
NOTE:
Engine coolant temperature is 25 °C (77 °F) or less before engine starts.
2. Warm up the engine. NOTE:
Raise engine coolant temperature until it reaches 65 °C (149 °F) or more.
3. Turn ignition switch OFF and wait at least 10 seconds. Check that throttle valve moves during the above 10 seconds by confirming the operating sound.
>> END
Revision: 2010 May2011 QX56

EC-148
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IDLE AIR VOLUME LEARNING
IDLE AIR VOLUME LEARNING
DescriptionINFOID:0000000006217750
Idle Air Volume Learning is a function of ECM to learn
the idle air volume that keeps engine idle speed within
the specific range. It must be perfo rmed under the following conditions:
 Each time the electric throttle control actuator or ECM is replaced.
 Idle speed or ignition timing is out of the specification.
Work ProcedureINFOID:0000000006217751
1.PRECONDITIONING
Check that all of the following conditions are satisfied.
Learning will be cancelled if any of the follo wing conditions are missed for even a moment.
 Battery voltage: More than 12.9 V (At idle)
 Engine coolant temperature: 70 - 105 °C (158 - 221 °F)
 Selector lever position: P or N
 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
started the headlamp will not illuminate.
 Steering wheel: Neutral (Straight-ahead position)
 Vehicle speed: Stopped
 Transmission: Warmed-up
- With CONSULT-III: Drive vehicle until “ATF TEMP 2” in “DATA MONITOR” mode of “A/T” system indicates
less than 0.9 V.
- Without CONSULT-III: Drive vehicle for 10 minutes.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 3.
2.PERFORM IDLE AIR VOLUME LEARNING
WITH CONSULT-III
1. Perform Accelerator Pedal Released Position Learning. Refer to EC-146, "
Work Procedure".
2. Perform Throttle Valve Closed Position Learning. EC-147, "
Work Procedure".
3. Start engine and warm it up to normal operating temperature.
4. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
5. Touch “START” and wait 20 seconds.
Is
“CMPLT” displayed on CONSULT-III screen?
YES >> GO TO 4.
NO >> GO TO 5.
3.PERFORM IDLE AIR VOLUME LEARNING
WITHOUT CONSULT-III
NOTE:
 It is better to count the ti me accurately with a clock.
 It is impossible to switch the di agnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
1. Perform Accelerator Pedal Released Position Learning. Refer to EC-146, "
Work Procedure".
2. Perform Throttle Valve Closed Position Learning. EC-147, "
Work Procedure".
3. Start engine and warm it up to normal operating temperature.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Confirm that accelerator pedal is fully releas ed, turn ignition switch ON and wait 3 seconds.
6. Repeat the following procedure quickly 5 times within 5 seconds.
- Fully depress the accelerator pedal.
- Fully release the accelerator pedal.
7. Wait 7 seconds, fully depress the accelerator pedal for approx. 20 seconds until the MIL stops blinking
and turns ON.
8. Fully release the accelerator pedal within 3 seconds after the MIL turns ON.
Revision: 2010 May2011 QX56

IDLE AIR VOLUME LEARNINGEC-149
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9. Start engine and let it idle.
10. Wait 20 seconds.
>> GO TO 4.
4.CHECK IDLE SPEED AND IGNITION TIMING
Rev up engine two or three times and check that idle speed and ignition timing are within the specifications.
For procedure, refer to EC-530, "
Inspection" and EC-531, "Inspection".
For specifications, refer to EC-538, "
Idle Speed" and EC-538, "Ignition Timing".
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 5.
5.DETECT MALFUNCTIONING PART-I
Check the following
 Check that throttle valve is fully closed.
 Check PCV valve operation.
 Check that downstream of throttle valve is free from air leakage.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair or replace malfunctioning part.
6.DETECT MALFUNCTIONING PART-II
Engine component parts and their installation conditi on are questionable. Check and eliminate the cause of
the incident.
It is useful to perform “TROUBLE DIAG NOSIS - SPECIFICATION VALUE”. Refer to EC-161, "
Description".
If any of the following conditions occur after the engi ne has started, eliminate the cause of the incident and
perform Idle Air Volume Learning again:
 Engine stalls.
 Incorrect idle.
>> INSPECTION END
SEC897C
Revision: 2010 May2011 QX56