Page 2532 of 5598
![INFINITI QX56 2011 Factory Service Manual
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 Inspecti INFINITI QX56 2011 Factory Service Manual
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 Inspecti](/manual-img/42/57033/w960_57033-2531.png)
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
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![INFINITI QX56 2011 Factory Service Manual
IGNITION SIGNALEC-509
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
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K L
M A
EC
NP
O
YES >> GO TO 10.
NO >> Repair open circuit or short to power in harness or connectors.
10.CHECK IGNITION COIL INFINITI QX56 2011 Factory Service Manual
IGNITION SIGNALEC-509
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
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K L
M A
EC
NP
O
YES >> GO TO 10.
NO >> Repair open circuit or short to power in harness or connectors.
10.CHECK IGNITION COIL](/manual-img/42/57033/w960_57033-2532.png)
IGNITION SIGNALEC-509
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
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EC
NP
O
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
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![INFINITI QX56 2011 Factory Service Manual
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 fus INFINITI QX56 2011 Factory Service Manual
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 fus](/manual-img/42/57033/w960_57033-2533.png)
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
Page 2548 of 5598
![INFINITI QX56 2011 Factory Service Manual
EC-524
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
SYMPTOM DIAGNOSIS
ENGINE CONTROL SYSTEM SYMPTOMS
Symptom TableINFOID:0000000006218028
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTO INFINITI QX56 2011 Factory Service Manual
EC-524
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
SYMPTOM DIAGNOSIS
ENGINE CONTROL SYSTEM SYMPTOMS
Symptom TableINFOID:0000000006218028
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTO](/manual-img/42/57033/w960_57033-2547.png)
EC-524
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
SYMPTOM DIAGNOSIS
ENGINE CONTROL SYSTEM SYMPTOMS
Symptom TableINFOID:0000000006218028
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Low pressure fuel pump circuit 11232 22 3 2 EC-512
Low fuel pressure sensor circuit 4 4EC-483
Fuel pressure regulator system 334444444 4EC-198
Fuel injector circuit 11232 22 2EC-498
Evaporative emission system 334444444 4EC-532
FRP sensor circuit 11222 22 2EC-276EC-279
High pressure fuel pump circuit 4 3
EC-501
Air Positive crankcase ventilation sys-
tem 334444444 41
EC-534
Incorrect idle speed adjustment 1 1 1 1 1 EC-139
Electric throttle control actuator 112332222 2 2EC-460EC-466
IgnitionIncorrect ignition timing adjustment33111 11 1
EC-139
Ignition circuit 11222 22 2EC-506
Main power supply and ground circuit 22333 33 23 EC-168
Revision: 2010 May2011 QX56
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ENGINE CONTROL SYSTEM SYMPTOMSEC-525
< SYMPTOM DIAGNOSIS > [VK56VD]
C
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EC
NP
O
Mass air flow sensor circuit
1
12 2
222 2 EC-201
Engine coolant temperature sensor circuit
333
EC-2 INFINITI QX56 2011 Factory Service Manual
ENGINE CONTROL SYSTEM SYMPTOMSEC-525
< SYMPTOM DIAGNOSIS > [VK56VD]
C
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Mass air flow sensor circuit
1
12 2
222 2 EC-201
Engine coolant temperature sensor circuit
333
EC-2](/manual-img/42/57033/w960_57033-2548.png)
ENGINE CONTROL SYSTEM SYMPTOMSEC-525
< SYMPTOM DIAGNOSIS > [VK56VD]
C
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Mass air flow sensor circuit
1
12 2
222 2 EC-201
Engine coolant temperature sensor circuit
333
EC-217
Air fuel ratio (A/F) sensor 1 circuit EC-181
EC-228
EC-232
EC-235
EC-238
Throttle position sensor circuit
22EC-219
EC-288
EC-406
EC-407
EC-475
Accelerator pedal position sensor circuit 3 2 1
EC-468EC-471
EC-478
Knock sensor circuit 2 3
EC-297
Engine oil temperature sensor 4 2 3EC-285
Crankshaft position sensor circuit 2 2EC-299
Camshaft position sensor circuit 3 2EC-303
Vehicle speed signal circuit 2 3 3 3EC-356
Power steering pressure sensor circuit 2 3 3EC-371
ECM 22333333333EC-376EC-378
EC-380
Intake valve timing control solenoid valve cir-
cuit
32 13223 3
EC-193
VVEL control module 3 4 4 3 EC-451EC-452
VVEL actuator motor 3 4 4 3
EC-390
VVEL actuator motor relay 3 4 4 3EC-393
VVEL control shaft position sensor 3 4 4 3EC-387
PNP signal circuit 3 3 3 3 3EC-383
Refrigerant pressure sensor circuit 2 3 3 4EC-520
Electrical load signal circuit 3EC-493
Air conditioner circuit 223333333 3 2HAC-60
ABS actuator and electric unit (control unit) 4BRC-60
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Revision: 2010 May2011 QX56
Page 2550 of 5598
![INFINITI QX56 2011 Factory Service Manual
EC-526
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Manifold absolut INFINITI QX56 2011 Factory Service Manual
EC-526
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Manifold absolut](/manual-img/42/57033/w960_57033-2549.png)
EC-526
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Manifold absolute pressure sensor circuit 3
EC-210
Battery current sensor 4 5 5 3EC-412EC-420
EC-424
Heated oxygen sensor 2 6 6 6 6 5EC-243EC-249
EC-257
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel tank 5
5 FL-4
Fuel piping 555 55 5
FL-4
Vapor lock —
Valve deposit 5 555 55 5 —
Poor fuel (Heavy weight gasoline,
Low octane) —
Revision: 2010 May2011 QX56
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![INFINITI QX56 2011 Factory Service Manual
ENGINE CONTROL SYSTEM SYMPTOMSEC-527
< SYMPTOM DIAGNOSIS > [VK56VD]
C
D
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F
G H
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M A
EC
NP
O
Air Air duct
55555 5 EM-28
Air cleaner
EM-27
Air leakage from air duct
(Mass air flow sensor — el INFINITI QX56 2011 Factory Service Manual
ENGINE CONTROL SYSTEM SYMPTOMSEC-527
< SYMPTOM DIAGNOSIS > [VK56VD]
C
D
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G H
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EC
NP
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Air Air duct
55555 5 EM-28
Air cleaner
EM-27
Air leakage from air duct
(Mass air flow sensor — el](/manual-img/42/57033/w960_57033-2550.png)
ENGINE CONTROL SYSTEM SYMPTOMSEC-527
< SYMPTOM DIAGNOSIS > [VK56VD]
C
D
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F
G H
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M A
EC
NP
O
Air Air duct
55555 5 EM-28
Air cleaner
EM-27
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555 EM-28
Electric throttle control actuator
EC-460
Air leakage from intake manifold/
Collector/GasketEM-30
Cranking Battery
111111
11
PG-161
Generator circuit
CHG-13
Starter circuit 3STR-11
Signal plate 6EM-106
PNP signal 4EC-383
Engine Cylinder head
55555 55 5 EM-92
Cylinder head gasket 4 3
Cylinder block
66666 66 6 4
EM-115
Piston
Piston ring
Connecting rod
Bearing
Crankshaft
Va l v e
mecha-
nism Timing chain
55555 55 5 EM-72
Camshaft
EM-77
Intake valve timing controlEM-61
Intake valve
3EM-92
Exhaust valve
Exhaust Exhaust manifold/Tube/Muffler/ Gasket 55555 55 5 EM-42
EX-6Three way catalystSYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Revision: 2010 May2011 QX56
Page 2552 of 5598
E C -528
< SYMPTOM DIAGNOSIS >[VK56VD]
ENGINE CONTROL SYSTEM SYMPTOMS
1 - 6: The numbers refer to the order of inspection.Lubrica-
tion
Oil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler 55555 55 5 EM-56
EM-60
LU-9
LU-12
LU-14
Oil level (Low)/Filthy oil
LU-7
Cooling
Radiator/Hose/Radiator filler cap
55555 55 45 CO-11
CO-11
Thermostat 5
CO-21
Water pumpCO-19
Water galleryEM-115
Cooling fan
5CO-17
Coolant level (Low)/Contaminat-
ed coolant
CO-8
IVIS (INFINITI Vehicle Immobilizer System —
NATS)11
SEC-48
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Revision: 2010 May2011 QX56