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
Page 2549 of 5598
![INFINITI QX56 2011 Factory Service Manual
ENGINE CONTROL SYSTEM SYMPTOMSEC-525
< SYMPTOM DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
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
D
E
F
G H
I
J
K L
M A
EC
NP
O
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
D
E
F
G H
I
J
K L
M A
EC
NP
O
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
Page 2551 of 5598
![INFINITI QX56 2011 Factory Service Manual
ENGINE CONTROL SYSTEM SYMPTOMSEC-527
< SYMPTOM DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
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
E
F
G H
I
J
K L
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](/manual-img/42/57033/w960_57033-2550.png)
ENGINE CONTROL SYSTEM SYMPTOMSEC-527
< SYMPTOM DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
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
Page 3684 of 5598

MA-14
< PERIODIC MAINTENANCE >
ENGINE MAINTENANCE
If water drain plug on cylinder block is removed, close and tighten it. Refer to EM-107, "Disassem-
bly and Assembly".
2. Check that each hose clamp is firmly tightened.
3. Remove air relief plug (1) on heater hose.
4. Fill radiator, and reservoir tank, to specified level. Pour engine coolant through engine coolant filler neck
slowly of less than 3 (2-5/8 lmp qt) a minute to allow air
in system to escape.
Use Genuine NISSAN Long Life Antifreeze/Coolant or
equivalent mixed with water (d istilled or demineralized).
Refer to MA-10, "
Fluids and Lubricants".
5. When engine coolant overflows air relief hole on heater hose, install air relief plug with clamp. Then refill
radiator with engine coolant.
6. Install radiator cap.
7. Install reservoir tank cap.
8. Warm up engine until opening thermostat less than 3,000 rpm. Check thermostat opening condition by touching radiator hose (lower) to see a flow of warm water.
CAUTION:
Watch water temperature gauge so as not to overheat engine.
9. Stop the engine and cool down to less than approximately 50 °C (122 °F).
Cool down using fan to reduce the time.
If necessary, refill radiator up to filler neck with engine coolant.
10. Refill reservoir tank to “MAX” level line with engine coolant if necessary.
11. Repeat steps 6 through 10 two or more times with reservoir tank cap installed until engine coolant level no longer drops. : 1.96 N·m (0.2 kg-m, 17 in-lb)
2. Engine cover
: Vehicle front
JPBIA3429ZZ
Engine coolant capacity : Refer to CO-23,
"PeriodicalMaintenanceS
pecification".
(With reservoir tank at
“MAX” level)JPBIA0412ZZ
Reservoir tank engine
coolant capacity :Refer to
CO-23,
"PeriodicalMaintenanceSp
ecification".
(At “MAX” level)
A : MAX
B: MIN
JPBIA0102ZZ
Revision: 2010 May2011 QX56