2010 INFINITI QX56 fuel pressure

BRC-14
< FUNCTION DIAGNOSIS >[VDC/TCS/ABS]
TCS
TCS
System DiagramINFOID:0000000005147950
System DescriptionINFOID:0000000005147951
• Traction Control System is a function that electronically controls engine torque, brake fluid pressure and A/T
gear position to ensure the optimum slippage ratio at drive wheels by computing wheel speed signals from 4
wheel sensors. When ABS actuator and electric unit (control unit) detects a spin at drive wheels (rear
wheels), it compares wheel speed signals from all 4 wheels. At this time, LH and RH rear brake fluid pres-
sure are controlled, while fuel being cut to engine and throttle valve being closed to reduce engine torque by
the control unit. Further more, throttle position is continuously controlled to ensure the optimum engine
torque at all times.
• During TCS operation, it informs driver of syst em operation by flashing SLIP indicator lamp.
• Electrical system diagnosis by CONSULT-III is available.
AWFIA0065GB
Revision: April 20092010 QX56

CCS
INSPECTION AND ADJUSTMENTCCS-5
< BASIC INSPECTION >
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INSPECTION AND ADJUSTMENT
ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT
ADDITIONAL SERVICE WHEN REPL ACING CONTROL UNIT : Description
INFOID:0000000005145971
Always perform the laser beam aiming adjustment after repl acing the ICC unit. In addition, test the ICC sys-
tem operations to see if it functions normally.
ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : Special Repair Re-
quirement
INFOID:0000000005145972
1.LASER BEAM AIMING ADJUSTMENT
Adjust laser beam aiming. Refer to CCS-5, "
LASER BEAM AIMING ADJUSTMENT : Outline of Laser Beam
Aiming Adjustment Procedure".
>> GO TO 2
2.ICC SYSTEM ACTION TEST
1. Perform the ICC system operation test. Refer to CCS-8, "
ACTION TEST : ICC System Running Test".
2. Check that the ICC system operates normally.
>> INSPECTION END.
LASER BEAM AIMI NG ADJUSTMENT
LASER BEAM AIMING ADJUSTMENT : Outlin e of Laser Beam Aiming Adjustment
Procedure
INFOID:0000000005145973
CAUTION:
• The laser beam aiming adjustment can not be performed without CONSULT-III.
• The laser beam aiming adjustment must be performed every time the ICC sensor is removed,
installed or has been moved as a result of a collision.
1. Prepare the vehicle and the work area.
2. Set up the ICC target board. For details, refer to Technical Service Bulletin.
3. Adjust the sensor following the procedure on CONSULT-III.
4. Check system operation after the adjustment.
LASER BEAM AIMING ADJU STMENT : PreparationINFOID:0000000005145974
• Place the vehicle on level ground. Shift the transmi ssion into "P" position and release the parking brake.
• Adjust the tire pressure to the specified value.
• See that there is no load in the vehicle. Coolant , engine oil and fuel should be filled to correct level.
• Check that the vehicle suspension has been adjusted to the standard height by the load leveling rear air sus-
pension system. Refer to SCS-7, "
CONSULT-III Function" .
• Clean the sensor with a soft cloth. Tool number : KV99110100 (J-45718)
LKIA0632E
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EC-6
On Board Diagnosis Logic .....................................353
DTC Confirmation Procedure ................................353
Diagnosis Procedure .............................................353
Component Inspection ...........................................355
P2100, P2103 THROTTLE CONTROL MO-
TOR RELAY .....................................................
356
Component Description ....................................... ..356
On Board Diagnosis Logic .....................................356
DTC Confirmation Procedure ................................356
Diagnosis Procedure .............................................356
P2101 ELECTRIC THROTTLE CONTROL
FUNCTION .......................................................
359
Description ........................................................... ..359
On Board Diagnosis Logic .....................................359
DTC Confirmation Procedure ................................359
Diagnosis Procedure .............................................359
Component Inspection ...........................................362
P2118 THROTTLE CONTROL MOTOR ..........363
Component Description ....................................... ..363
On Board Diagnosis Logic .....................................363
DTC Confirmation Procedure ................................363
Diagnosis Procedure .............................................363
Component Inspection ...........................................364
P2119 ELECTRIC THROTTLE CONTROL
ACTUATOR .....................................................
365
Component Description ....................................... ..365
On Board Diagnosis Logic .....................................365
DTC Confirmation Procedure ................................365
Diagnosis Procedure .............................................366
P2122, P2123 APP SENSOR ..........................367
Component Description ....................................... ..367
On Board Diagnosis Logic .....................................367
DTC Confirmation Procedure ................................367
Diagnosis Procedure .............................................367
Component Inspection ...........................................369
P2127, P2128 APP SENSOR ..........................370
Component Description ....................................... ..370
On Board Diagnosis Logic .....................................370
DTC Confirmation Procedure ................................370
Diagnosis Procedure .............................................370
Component Inspection ...........................................373
P2135 TP SENSOR .........................................374
Component Description ....................................... ..374
On Board Diagnosis Logic .....................................374
DTC Confirmation Procedure ................................374
Diagnosis Procedure .............................................374
Component Inspection ...........................................377
P2138 APP SENSOR ......................................378
Component Description ....................................... ..378
On Board Diagnosis Logic .....................................378
DTC Confirmation Procedure ................................378
Diagnosis Procedure .............................................379
Component Inspection ......................................... .381
P2A00, P2A03 A/F SENSOR 1 ........................382
Component Description ....................................... .382
On Board Diagnosis Logic ....................................382
DTC Confirmation Procedure ................................382
Diagnosis Procedure .............................................383
ASCD BRAKE SWITCH ...................................388
Component Description ....................................... .388
Diagnosis Procedure .............................................388
Component Inspection ..........................................390
ASCD INDICATOR ...........................................391
Component Description ....................................... .391
Diagnosis Procedure .............................................391
COOLING FAN .................................................392
Diagnosis Procedure ............................................ .392
Component Inspection ..........................................392
ELECTRICAL LOAD SIGNAL ..........................394
Description ........................................................... .394
Diagnosis Procedure .............................................394
FUEL INJECTOR ..............................................396
Component Description ....................................... .396
Diagnosis Procedure .............................................396
Component Inspection ..........................................398
FUEL PUMP .....................................................399
Description ........................................................... .399
Diagnosis Procedure .............................................399
Component Inspection ..........................................402
ICC BRAKE SWITCH ..................................... ..403
Component Description ....................................... .403
Diagnosis Procedure .............................................403
Component Inspection ..........................................405
IGNITION SIGNAL ............................................407
Component Description ....................................... .407
Diagnosis Procedure .............................................407
Component Inspection ..........................................410
ON BOARD REFUELING VAPOR RECOV-
ERY (ORVR) .....................................................
412
System Description .............................................. .412
Diagnosis Procedure .............................................412
Component Inspection ..........................................414
POSITIVE CRANKCASE VENTILATION .........417
Description ........................................................... .417
Component Inspection ..........................................417
REFRIGERANT PRESSURE SENSOR ...........419
Component Description ....................................... .419
Diagnosis Procedure .............................................419
ECU DIAGNOSIS ......................................422
ECM ................................................................ ..422
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EC-7
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CONSULT-lll Reference Va
lue in Data Monitor
Mode ................................................................... ..
422
ECM Harness Connector Terminal Layout ...........425
ECM Terminal and Reference Value ....................425
Wiring Diagram - ENGINE CONTROL SYSTEM - ..435
Fail-Safe Chart .................................................... ..456
DTC Inspection Priority Chart ............................. ..458
DTC Index ........................................................... ..459
Emission-related Diagnostic Information ...............463
SYMPTOM DIAGNOSIS ..... .......................477
ENGINE CONTROL SYSTEM SYMPTOMS .. ..477
Symptom Matrix Chart ........................................ ..477
NORMAL OPERATING CONDITION ...............481
Fuel Cut Control (at No Load and High Engine
Speed) ................................................................. ..
481
PRECAUTION ............................................482
PRECAUTIONS .............................................. ..482
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ..
482
On Board Diagnosis (OBD) System of Engine and
A/T .........................................................................
482
Precaution .............................................................482
PREPARATION .........................................486
PREPARATION .............................................. ..486
Special Service Tool ........................................... ..486
Commercial Service Tool ......................................487
ON-VEHICLE MAINTENANCE ..................489
FUEL PRESSURE ...........................................489
Fuel Pressure Check ........................................... ..489
EVAP LEAK CHECK ......................................491
How to Detect Fuel Vapor Leakage .......................491
ON-VEHICLE REPAIR ...............................493
EVAP CANISTER ............................................493
Removal and Installation ..................................... ..493
Component Inspection ...........................................493
INTAKE VALVE TIMING CONTROL ..............494
Intake Valve Timing Control Solenoid Valve (LH) ..494
Intake Valve Timing Cont rol Solenoid Valve (RH) ..494
Intake Valve Timing Control Position Sensor (LH) ..495
Intake Valve Timing Control Position Sensor (RH) ..495
Camshaft Position Sensor (PHASE) .....................495
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... .......................................... .
497
SERVICE DATA AND SPECIFICATIONS
(SDS) ...............................................................
497
Fuel Pressure ...................................................... ..497
Idle Speed and Ignition Timing ..............................497
Calculated Load Value ..........................................497
Mass Air Flow Sensor ............................................497
Intake Air Temperature Sensor .............................497
Engine Coolant Temperature Sensor ....................497
A/F Sensor 1 Heater ..............................................497
Heated Oxygen sensor 2 Heater ...........................498
Crankshaft Position Sensor (POS) ........................498
Camshaft Position Sensor (PHASE) .....................498
Throttle Control Motor ............................................498
Fuel Injector ...........................................................498
Fuel Pump .............................................................498
Revision: April 20092010 QX56

EC-22
< FUNCTION DIAGNOSIS >[VK56DE]
ENGINE CONTROL SYSTEM
Engine Control Comp onent Parts Location
INFOID:0000000005149063
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. I gnition 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 valve 21. Knock sensor (bank 2)
22. Fuel injector (bank 2) 23. A/F sensor 1 (bank 2) 24. IPDM E/R
BBIA0743E
Revision: April 20092010 QX56

ENGINE CONTROL SYSTEMEC-25
< FUNCTION DIAGNOSIS > [VK56DE]
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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 front grille removed) 12. Intake valve timing control position
sensor (bank 2) (view with engine
cover and intake air duct removed)
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)
: Vehicle front
BBIA0774E
Revision: April 20092010 QX56

EC-28
< FUNCTION DIAGNOSIS >[VK56DE]
MULTIPORT FUEL INJECTION SYSTEM
MULTIPORT FUEL INJECTION SYSTEM
System DescriptionINFOID:0000000005149064
INPUT/OUTPUT SIGNAL CHART
*1: This sensor is not used to control the engine system. This is used only for the on board diagnosis.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
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 engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.
VARIOUS FUEL INJECTION I NCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated 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 is changed from N to D
• High-load, high-speed operation

• During deceleration
• During high engine speed operation
Sensor Input signal to ECMECM functionActuator
Crankshaft position sensor (POS) Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector
Camshaft position sensor (PHASE)
Mass air flow sensor
Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
TCM Gear position
Knock sensor Engine knocking condition
Battery Battery voltage*
3
Power steering pressure sensorPower steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit) VDC/TCS operation command*
2
Air conditioner switchAir conditioner operation*2
Wheel sensorVehicle speed*2
Revision: April 20092010 QX56

EC-64
< FUNCTION DIAGNOSIS >[VK56DE]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
ItemDIAGNOSTIC TEST MODE
WORK SUP-
PORT SELF-DIAGNOSTIC
RESULTS DATA
MONI-
TOR ACTIVE
TEST DTC & SRT
CONFIRMATION
DTC*1 FREEZE
FRAME
DATA*2 SRT
STATUS DTC
WORK
SUP-
PORT
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor (POS) ×××
Camshaft position sensor (PHASE) ×××
Mass air flow sensor ××
Engine coolant temperature sensor ××××
Air fuel ratio (A/F) sensor 1 ××× ×
Heated oxygen sensor 2 ××× ×
Wheel sensor ×××
Accelerator pedal position sensor ××
Throttle position sensor ×××
Fuel tank temperature sensor ×××
EVAP control system pressure sen-
sor ××
Intake air temperature sensor ×××
Knock sensor ×
Refrigerant pressure sensor ×
Closed throttle position switch (ac-
celerator pedal position sensor sig-
nal) ×
Air conditioner switch ×
Park/neutral position (PNP) signal ××
Stop lamp switch ××
Power steering pressure sensor ××
Battery voltage ×
Load signal ×
Intake valve timing control position
sensor ××
Fuel level sensor ××
Battery current sensor ××
ICC steering switch ××
ASCD steering switch ××
ICC brake switch ××
ASCD brake switch ××
Revision: April 20092010 QX56