2007 INFINITI QX56 engine

TROUBLE DIAGNOSIS
EC-91
< SERVICE INFORMATION >
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1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Camshaft position sensor (PHASE) circuit 3 2EC-342
Vehicle speed signal circuit 2 3 3 3EC-429
Power steering pressure sensor circuit 2 3 3EC-435
ECM 22333333333EC-440,
EC-444
Intake valve timing control solenoid valve cir-
cuit32 13223 3EC-178
Park/Neutral position (PNP) switch circuit 3 3 3 3 3EC-452
Refrigerant pressure sensor circuit 2 3 3 4EC-638
Electrical load signal circuit 3EC-606
Air conditioner circuit 223333333 3 2AT C - 3 0
ABS actuator and electric unit (control unit) 4EC-467
,
EC-468

or BRC-11
SYMPTOM
Refer-
ence 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

EC-92
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
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
5FL-10
Fuel piping 5 5 5 5 5 5FL-4
Va p o r l o c k—
Valve deposit
5 555 55 5—
Poor fuel (Heavy weight gasoline,
Low octane)—
Air Air duct
55555 5EM-15
Air cleanerEM-15
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555EM-15
Electric throttle control actuatorEM-17
Air leakage from intake manifold/
Collector/GasketEM-17
Cranking Battery
111111
11SC-4
Generator circuitSC-15
Starter circuit 3SC-9
Signal plate 6EM-38
Park/Neutral position (PNP)
switch4AT- 9 9
Engine Cylinder head
55555 55 5EM-64
Cylinder head gasket 4 3
Cylinder block
66666 66 64
EM-78
Piston
Piston ring
Connecting rod
Bearing
Crankshaft
Va l v e
mecha-
nismTiming chain
55555 55 5EM-38
CamshaftEM-46
Intake valve timing controlEM-46
Intake valve
3EM-64
Exhaust valve

TROUBLE DIAGNOSIS
EC-93
< SERVICE INFORMATION >
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1 - 6: The numbers refer to the order of inspection.Exhaust Exhaust manifold/Tube/Muffler/
Gasket
55555 55 5EM-21
, EX-
3Three way catalyst
Lubrica-
tionOil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler
55555 55 5EM-24
, LU-
14 , LU-11 ,
LU-12
Oil level (Low)/Filthy oilLU-8
Cooling Radiator/Hose/Radiator filler cap
55555 55 45CO-13
Thermostat 5CO-20
Water pumpCO-18
Water galleryCO-8
Cooling fan 5CO-16
Coolant level (Low)/Contaminat-
ed coolant5CO-9
IVIS (INFINITI Vehicle Immobilizer System —
NATS)11BL-116
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

EC-94
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Engine Control Component Parts Location
INFOID:0000000003531621
1. ECM 2. Battery current sensor 3. Power steering pressure sensor
4. Ignition coil (with power transistor)
and spark plug (bank 2)5. Refrigerant pressure sensor 6. Intake valve timing control position
sensor (bank 2)
7. Intake valve timing control solenoid
valve (bank 2)8. Engine coolant temperature sensor 9. Electric throttle control actuator
10. Intake valve timing control position
sensor (bank 1)11. Intake valve timing control solenoid
valve (bank 1)12. Cooling fan motor
13. Camshaft position sensor (PHASE) 14. Ignition coil (with power transistor)
and spark plug (bank 1)15. Mass air flow sensor (with intake air
temperature sensor)
16. A/F sensor 1 (bank 1) 17. EVAP service port 18. Fuel injector (bank 1)
19. Knock sensor (bank 1) 20. EVAP canister purge volume control
solenoid valve21. Knock sensor (bank 2)
22. Fuel injector (bank 2) 23. A/F sensor 1 (bank 2) 24. IPDM E/R
BBIA0743E

TROUBLE DIAGNOSIS
EC-95
< SERVICE INFORMATION >
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1. Body ground (view with battery re-
moved)2. Body ground (view with battery re-
moved)3. Body ground
4. No. 1 ignition coil 5. Engine ground 6. Mass air flow sensor (with intake air
temperature sensor)
7. IPDM E/R 8. Battery 9. Radiator hose
10. Camshaft position sensor (PHASE) 11. Electric throttle control actuator
(view with intake air duct removed)12. Cooling fan motor harness connec-
tor
BBIA0778E

EC-96
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
1. EVAP canister purge volume control
solenoid valve (view with engine
cover removed)2. EVAP service port (view with engine
cover removed)3. Crankshaft position sensor (POS)
(view from under the vehicle)
4. Engine oil pan (view from under the
vehicle)5. Condenser-1 6. Brake fluid reservoir
7. EVAP canister (view with fuel tank
removed)8. EVAP control system pressure sen-
sor (view with fuel tank removed)9. EVAP canister vent control valve
(view with fuel tank removed)
10. Rear suspension member (view with
fuel tank removed)11. Refrigerant pressure sensor (view
with hood open)12. Intake valve timing control position
sensor (bank 2) (view with engine
cover and intake air duct removed)
BBIA0783E

TROUBLE DIAGNOSIS
EC-97
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13. Intake valve timing control position
sensor (bank 1) (view with engine
cover and intake air duct removed)14. Intake valve timing control solenoid
valve (bank 2) (view with engine cov-
er and intake air duct removed)15. Drive belt (view with engine cover
and intake air duct removed)
16. Radiator hose (view with engine cov-
er and intake air duct removed)17. Intake valve timing control solenoid
valve (bank 1) (view with engine cov-
er and intake air duct removed)
1. Knock sensor (bank 1) (view with en-
gine removed)2. Knock sensor (bank 2) (view with en-
gine removed)3. Battery current sensor
4. Power steering pressure sensor 5. Power steering fluid reservoir 6. Intake manifold
7. Engine coolant temperature sensor 8. Ignition coils (with power transistor) 9. Ignition coil (with power transistor)
10. Injector harness connectors (bank 2) 11. Injector harness connectors (bank 1)
BBIA0774E

TROUBLE DIAGNOSIS
EC-103
< SERVICE INFORMATION >
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ECM Harness Connector Terminal LayoutINFOID:0000000003531624
ECM Terminal and Reference ValueINFOID:0000000003531625
PREPARATION
ECM is located in the engine room passenger side behind battery.
ECM INSPECTION TABLE
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECMs transistor. Use a ground other than ECM terminals, such as the ground.
PBIB3368E
BBIA0386E
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
1 B ECM ground[Engine is running]
• Idle speedBody ground
2 LG/B A/F sensor 1 heater (bank 1)[Engine is running]
•Warm-up condition
• Idle speed
(More than 140 seconds after starting en-
gine)Approximately 2.9 - 8.8V
3LThrottle control motor relay
power supply[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
4 L/W Throttle control motor (Close)[Ignition switch: ON]
• Engine: Stopped
• Selector lever: D
• Accelerator pedal: Fully released0 - 14V
PBIA8148J
PBIB1104E