2011 INFINITI QX56 Coil

EC-310
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0420, P0430 THREE
WAY CATALYST FUNCTION
6. Remove all ignition coil harness connectors to avoi d the electrical discharge from the ignition coils.
7. Remove ignition coil and spark plug of the cylinder to be checked.
8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
9. Connect spark plug and harness connector to ignition coil.
10. Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 - 0.66 in) between the edge of the spark plug and grounded metal
portion as shown in the figure.
11. Crank engine for approximately 3 seconds, and check whether spark is generated between the spark plug and the grounded
metal portion.
CAUTION:
 Never place the spark plug and the ignition coil within 50
cm (19.7 in) each other. Be careful not to get an electrical
shock while checking, becau se the electrical discharge
voltage becomes 20 kV or more.
 It might damage the ignition coil if the gap of more than 17 mm (0.66 in) is made.
NOTE:
When the gap is less than 13 mm (0.52 in), a spark might be generated even if the coil is malfunc-
tioning.
Is the inspection result normal?
YES >> GO TO 10.
NO >> GO TO 7.
7.CHECK FUNCTION OF IGNITION COIL-II
1. Turn ignition switch OFF.
2. Disconnect spark plug and connect a non-malfunctioning spark plug.
3. Crank engine for approximately 3 seconds, and rec heck whether spark is generated between the spark
plug and the grounded metal portion.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Check ignition coil, power transistor and their circuits. Refer to EC-506, "
Diagnosis Procedure".
8.CHECK SPARK PLUG
Check the initial spark plug for fouling, etc.
Is the inspection result normal?
YES >> Replace spark plug(s) with standard type one(s). For spark plug type, refer to EM-132, "
Spark Plug".
NO >> Repair or clean spark plug. Then GO TO 9.
9.CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for approximately 3 seconds, and rec heck whether spark is generated between the spark
plug and the grounded portion.
Is the inspection result normal?
YES >> INSPECTION END Spark should be generated.
JMBIA0066GB
Spark should be generated.
SEF156I
Spark should be generated.
Revision: 2010 May2011 QX56

P0420, P0430 THREE WAY CATALYST FUNCTIONEC-311
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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NO >> Replace spark plug(s) with standard type one(s). For spark plug type, refer to
EM-132, "Spar k
Plug".
10.CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Remove fuel injector assembly. Refer to EM-49, "
Removal and Installation".
Keep fuel hose and all fuel injectors connected to fuel tube.
3. Disconnect all ignition coil harness connectors.
4. Reconnect all fuel injector harness connectors disconnected.
5. Turn ignition switch ON.
6. Check that fuel does not drip from fuel injector.
Does fuel drip from fuel injector?
YES >> Replace the fuel injector(s) from which fuel is dripping.
NO >> GO TO 11.
11 .CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
Is the inspection result normal?
YES >> Replace three way catalyst assembly.
NO >> Repair or replace harness or connector.
Revision: 2010 May2011 QX56

EC-506
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
IGNITION SIGNAL
IGNITION SIGNAL
Component Function CheckINFOID:0000000006218011
1.INSPECTION START
Turn ignition switch OFF, and restart engine.
Does the engine start?
YES-1 >> With CONSULT-III: GO TO 2.
YES-2 >> Without CONSULT-III: GO TO 3.
NO >> Go to EC-506, "
Diagnosis Procedure".
2.CHECK IGNITION SIGNAL FUNCTION
WITH CONSULT-III
1. Perform “POWER BALANCE” in “A CTIVE TEST” mode with CONSULT-III.
2. Check that each circuit produces a momentary engine speed drop.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-506, "
Diagnosis Procedure".
3.CHECK IGNITION SIGNAL FUNCTION
WITHOUT CONSULT-III
1. Let engine idle.
2. Read the voltage signal between ECM harness connector terminals under the following conditions with an oscilloscope.
NOTE:
The pulse cycle changes depending on rpm at idle.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-506, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006218012
1.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF, wait at least 10 seconds and then turn it ON.
2. Check the voltage between ECM harness connector terminals under the following conditions.
ECM
Voltage signal
Cylinder +–
Connector Terminal Connector Terminal
1
F 111 12
E80 175
213
314
415
517
618
719
820
PBIB0044E
Revision: 2010 May2011 QX56

IGNITION SIGNALEC-507
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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Is the inspection result normal?
YES >> GO TO 2.
NO >> Go to
EC-168, "
Diagnosis Procedure".
2.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Turn ignition switch ON.
4. Check the voltage between condenser harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 3.
3.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector E7.
3. Check the continuity between IPDM E/R harness connector and condenser harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> Go to EC-168, "Diagnosis Procedure".
NO >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open or short between IPDM E/R and condenser
 Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
5.CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check the continuity between condenser harness connector and ground.
3. Also check harness for short to power.
Is the inspection result normal?
ECM
Vo l ta g e
Connector +–
Terminal Terminal
E80 171
175 Battery voltage
172
Condenser Ground Voltage
Connector Terminal
F8 1 Ground Battery voltage
IPDM E/R Condenser Continuity
Connector Terminal Connector Terminal
E15 61 F8 1 Existed
Condenser Ground Continuity
Connector Terminal
F8 2 Ground Existed
Revision: 2010 May2011 QX56

EC-508
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
IGNITION SIGNAL
YES >> GO TO 6.
NO >> Repair open circuit or short to power in harness or connectors.
6.CHECK CONDENSER
Refer to EC-510, "
Component Inspection (Condenser)"
Is the inspection result normal?
YES >> GO TO 7.
NO >> Replace condenser.
7.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
1. Reconnect all harness connectors disconnected.
2. Disconnect ignition coil harness connector.
3. Turn ignition switch ON.
4. Check the voltage between ignition coil harness connector and ground.
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
 Harness connector F22 and E46
 Harness for open or short between ignition coil and harness connector F22
>> Repair or replace harness or connectors.
9.CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check the continuity between ignition coil harness connector and ground.
3. Also check harness for short to power.
Is the inspection result normal?
Ignition coil Ground Voltage
Cylinder Connector Terminal
1F75 3
Ground Battery voltage
2F76 3
3F77 3
4F78 3
5F79 3
6F80 3
7F81 3
8F82 3
Ignition coil
Ground Continuity
Cylinder Connector Terminal
1F75 2
Ground Existed
2F76 2
3F77 2
4F78 2
5F79 2
6F80 2
7F81 2
8F82 2
Revision: 2010 May2011 QX56

IGNITION SIGNALEC-509
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YES >> GO TO 10.
NO >> Repair open circuit or short to power in harness or connectors.
10.CHECK IGNITION COIL OUTPUT SI
GNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check the continuity between ignition coil harness connector and ECM harness connector.
3. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 11.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
11 .CHECK IGNITION COIL WITH POWER TRANSISTOR
Refer to EC-509, "
Component Inspection (Ignition Coil with Power Transistor)".
Is the inspection result normal?
YES >> GO TO 12.
NO >> Replace malfunctioning ignition coil with power transistor.
12.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (Ignition Coil with Power Transistor)INFOID:0000000006218013
1.CHECK IGNITION COIL WITH POWER TRANSISTOR-I
1. Turn ignition switch OFF.
2. Disconnect ignition coil harness connector.
3. Check resistance between ignition coil terminals as per the following.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace malfunctioning ignition coil with power transistor.
2.CHECK IGNITION COIL WITH POWER TRANSISTOR-II
CAUTION:
Perform the following procedure in a place with no combustible objects and good ventilation.
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
Ignition coil ECM Continuity
Cylinder Connector Terminal Connector Terminal
1F75 1
F 11112
Existed
2F76 1 13
3F77 1 14
4F78 1 15
5F79 1 17
6F80 1 18
7F81 1 19
8F82 1 20
Terminals Resistance [at 25
°C (77 °F)]
1 and 2 Except 0 or ∞ Ω
1 and 3 Except 0 Ω
2 and 3
Revision: 2010 May2011 QX56

EC-510
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
IGNITION SIGNAL
3. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
NOTE:
 For the fuse number, refer to EC-114, "
Wiring Diagram".
 For the fuse arrangement, refer to PG-143, "
Fuse, Connector and Terminal Arrangement".
 Do not use CONSULT-III to release fuel pressure , or fuel pressure applies again during the following
procedure.
4. Start engine.
5. After engine stalls, crank it 2 or 3 times to release all fuel pressure.
6. Turn ignition switch OFF.
7. Remove all ignition coil harness connectors to avoi d the electrical discharge from the ignition coils.
8. Remove ignition coil and spark plug of the cylinder to be checked.
9. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
10. Connect spark plug and harness connector to ignition coil.
11. Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 - 0.66 in) between the edge of the spark plug and grounded metal
portion as shown in the figure.
12. Crank engine for approximately 3 seconds, and check whether
spark is generated between the spark plug and the grounded
metal portion.
CAUTION:
 Never place the spark plug and the ignition coil within 50
cm (19.7 in) each other. Be careful not to get an electrical
shock while checking, becau se the electrical discharge
voltage becomes 20 kV or more.
 It might damage the ignition coil if the gap of more than 17 mm (0.66 in) is made.
NOTE:
When the gap is less than 13 mm (0.52 in), a spark might be generated even if the coil is malfunc-
tioning.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace malfunctioning ignition coil with power transistor.
Component Inspection (Condenser)INFOID:0000000006218014
1.CHECK CONDENSER
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Check resistance between condenser terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace condenser. Spark should be generated.
JMBIA0066GB
Terminals Resistance
1 and 2 Above 1 M Ω [at 25 °C (77 °F)]
Revision: 2010 May2011 QX56

EM-1
ENGINE
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CONTENTS
ENGINE MECHANICAL
PRECAUTION ................ ...............................3
PRECAUTIONS .............................................. .....3
Precaution for Procedure without Cowl Top Cover ......3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ...................................................................
3
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect .....................................
3
Precaution for Drain Engine Coolant and Engine
Oil ..............................................................................
4
Precaution for Disconnecting Fuel Piping .................4
Precaution for Handling High Pressure Fuel Sys-
tem ............................................................................
4
Precaution for Removal and Disassembly ................4
Precaution for Inspection, Repair and Replace-
ment ..........................................................................
4
Precaution for Assembly and Installation ..................4
Parts Requiring Angle Tightening .............................5
Precaution for Liquid Gasket .....................................5
Definitions of Bank Names ........................................6
PREPARATION ............................................7
PREPARATION .............................................. .....7
Special Service Tool ........................................... ......7
Commercial Service Tool ..........................................9
BASIC INSPECTION ...................................12
CAMSHAFT VALVE CLEARANCE ............... ....12
Inspection ............................................................ ....12
COMPRESSION PRESSURE ............................16
Inspection ............................................................ ....16
SYMPTOM DIAGNOSIS ..............................18
NOISE, VIBRATION AND HARSHNESS
(NVH) TROUBLESHOOTING ........................ ....
18
NVH Troubleshooting - Engine Noise .............. ....18
Use the Chart Below to Help You Find the C
ause of the Symptom ........................................ ....
19
PERIODIC MAINTENANCE ........................20
DRIVE BELTS ...................................................20
Exploded View ..................................................... ....20
Checking ..................................................................20
Tension Adjustment ................................................20
Removal and Installation .........................................20
Inspection ................................................................21
AIR CLEANER FILTER .....................................22
Exploded View .........................................................22
Removal and Installation .........................................22
SPARK PLUG ...................................................23
Exploded View .........................................................23
Removal and Installation .........................................23
Inspection ................................................................24
REMOVAL AND INSTALLATION ...............25
ENGINE COVER ...............................................25
Exploded View ..................................................... ....25
Removal and Installation .........................................25
DRIVE BELT AUTO TENSIONER AND IDLER
PULLEY .............................................................
26
Exploded View .........................................................26
Removal and Installation .........................................26
AIR CLEANER AND AIR DUCT .......................27
Exploded View .........................................................27
Removal and Installation .........................................27
Inspection ................................................................28
IGNITION COIL .................................................29
Exploded View .........................................................29
Removal and Installation .........................................29
INTAKE MANIFOLD .........................................30
Exploded View .........................................................30
Revision: 2010 May2011 QX56