fuel consumption INFINITI QX56 2011 Factory Service Manual

AV-26
< SYSTEM DESCRIPTION >
SYSTEM
Color and blinking cycle of sonar indicator
Sonar Buzzer Operation
 Each sonar sensor transmits a sensor signal to the sonar control unit when detecting an obstacle.
 The sonar control unit converts a signal received from each sonar sensor into distance and transmits detec-
tion distance signal to the AV control unit via AV communication.
 The AV control unit transmits a buzzer signal to t he BOSE amp. corresponding to each sonar sensor based
on the received signal.
 When receiving a buzzer signal, the BOSE amp. trans mits the buzzer signal to the each speaker. When
each speaker receives a buzzer signal, a buzzer sounds.
 When the front corner sensor detects an obstacle, a buzzer is heard from the speakers on the front side.
 When the rear corner sensor detects an obstacle, a buzzer is heard from the speakers on the rear side.
 It changes the buzzer cycle in 3 stages according to the detection distance.
Sonar buzzer cycle
VEHICLE INFORMATION FUNCTION
 Status of audio, climate control system, fuel economy, maintenance and navigation are displayed.
 AV control unit displays the fuel consumption status while receiving data signal through CAN communication from ECM and combination meter.
 AV control unit is connected to BCM via CAN communica tion transmitting/receiving for the vehicle settings
function.
AUTO LIGHT ADJUSTMENT SYSTEM
JSNIA3149GB
JSNIA3150GB
Revision: 2010 May2011 QX56

CHG-8
< SYSTEM DESCRIPTION >
SYSTEM
scription
INFOID:0000000006274863
By performing the power generation voltage variable c ontrol, the engine load due to the power generation of
the alternator is reduced and fuel consumption is decreased.
NOTE:
When any malfunction is detected in the power generat ion voltage variable control system, the power genera-
tion is performed according to the characteristic of the IC voltage regulator of the alternator.
Revision: 2010 May2011 QX56

SYSTEMEC-37
< SYSTEM DESCRIPTION > [VK56VD]
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*1: This sensor is not used to control the engine system under normal conditions.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The adoption of the direct fuel injection method enables
more accurate adjustment of fuel injection quantity by
injecting atomized high-pressure fuel directly into the cylinder. This method allows high-powered engine, low
fuel consumption, and emissions-reduction.
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). T he amount of fuel injected is a program value in the
ECM memory. The program value is preset by engi ne operating conditions. These conditions are determined
by input signals (for engine speed and intake air and fuel rail pressure) from the crankshaft position sensor,
camshaft position sensor, mass air flow sensor and the fuel rail pressure sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compens ated to improve engine performance under various operat-
ing conditions as listed below.
 During warm-up
 When starting the engine
 During acceleration
 Hot-engine operation
 When selector lever position is changed from N to D
 High-load, high-speed operation

 During deceleration
 During high engine speed operation
FUEL INJECTION CONTROL
Stratified-charge Combustion
Stratified-charge combustion is a combustion method wh ich enables extremely lean combustion by injecting
fuel in the latter half of a compression process, coll ecting combustible air-fuel around the spark plug, and form-
ing fuel-free airspace around the mixture.
Right after a start with the engine cold, the catalyst warm-up is accelerated by stratified-charge combustion.
Homogeneous Combustion
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor Engine speed*
2
Fuel injection
& mixture ratio
controlFuel injector
Camshaft position sensor Camshaft position
Mass air flow sensor Amount of intake air
Intake air temperature sensor Intake air temperature
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Fuel rail pressure sensor Fuel rail pressure
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
TCM Gear position
Battery
Battery voltage*
2
Knock sensor Engine knocking condition
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit) VDC/TCS operation command
A/C auto amp. A/C ON signal
Combination meter Vehicle speed
Revision: 2010 May2011 QX56

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

ENGINE CONTROL SYSTEM SYMPTOMSEC-525
< SYMPTOM DIAGNOSIS > [VK56VD]
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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

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

ENGINE CONTROL SYSTEM SYMPTOMSEC-527
< SYMPTOM DIAGNOSIS > [VK56VD]
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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

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

LAN-28
< SYSTEM DESCRIPTION >[CAN]
SYSTEM
Check CAN system type from the vehicle shape and equipment.
CAN COMMUNICATION SYSTEM : CA
N Communication Signal ChartINFOID:0000000006220533
Refer to LAN-17, "How to Use CAN Communication Signal Chart" for how to use CAN communication signal
chart.
T: Transmit R: Receive
1. ICC sensor
A. With ICC system
JSMIA0342ZZ
Signal nameECM
4WD
ABS
TCM
A-BAG
AFSAV
BCM
CGW
HVAC
M&A
STRG
TPMS
IPDM-E ADP
PSB
E-SUS ICC
PWBD
A/C compressor request
signal TR
Accelerator pedal position
signal TRRR
R
ASCD OD cancel request
signal TR
ASCD operation signal T R
ASCD status signal T R
Closed throttle position sig-
nal TR
R
Cooling fan speed request
signal TR
Engine and A/T integrated
control signal TR
RT
Engine coolant temperature
signal TRR
Engine restart request sig-
nal TRR
TR
Engine speed signal T R R R R R R R
Engine status signal T R R R
Engine torque signal T R
Fuel consumption monitor
signal TRR
ICC brake switch signal T R
ICC prohibition signal T R
ICC steering switch signal T R
Malfunctioning indicator
lamp signal TR
N idle instruction signal TR
RT
Revision: 2010 May2011 QX56

MWI
COMPONENT PARTSMWI-7
< SYSTEM DESCRIPTION >
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METER SYSTEM : Com ponent DescriptionINFOID:0000000006221691
CLOCK
Unit Description
Combination meter Controls the following with the signals received from each unit via CAN communication and the sig-
nals from switches and sensors.
 Speedometer
 Tachometer
 Engine coolant temperature gauge
 Fuel gauge
 Engine oil pressure gauge
 Voltmeter
 Warning lamps
 Indicator lamps
 Meter illumination control
 Meter effect function
 Information display
Trip computer switch Transmits the following signals to the combination meter.
 Enter switch signal
 Select switch signal
Trip reset and illumination con-
trol switch Transmits the following signals to the combination meter.
 Trip reset switch signal
 Illumination control switch signal (+)
 Illumination control switch signal (
−)
ECM Transmits the following signals to the combination meter via CAN communication.
 Engine speed signal
 Engine coolant temperature signal
 Engine status signal
 Fuel consumption monitor signal
ABS actuator and electric unit
(control unit) Transmits the vehicle speed signal to the combination meter via CAN communication.
IPDM E/R Transmits the oil pressure switch signal to the BCM via CAN communication.
BCM Transmits the following signals to the combination meter via CAN communication.
 Oil pressure switch signal
 Position light request signal
 Dimmer signal
 Door switch signal
 Meter ring illumination request signal
 Starter relay status signal
TCM Transmits the shift position signal to the combination meter via CAN communication.
A/T shift selector Transmits the following signals to the combination meter.
 Manual mode signal
 Non-manual mode signal
 Manual mode shift up signal
 Manual mode shift down signal
Fuel level sensor unit Transmits the fuel level sensor signal to the combination meter.
Oil pressure switch Transmits the oil pressure switch signal to the IPDM E/R.
Ambient sensor Transmits the ambient sensor signal to the combination meter.
A/C auto amp. Transmits the A/C auto amp. connection recognition signal to the combination meter.
Parking brake switch Transmits the parking brake switch signal to the combination meter.
Washer level switch Transmits the washer level switch signal to the combination meter.
Revision: 2010 May2011 QX56