2010 INFINITI QX56 steering

DLN-242
< SYMPTOM DIAGNOSIS >[REAR FINAL DRIVE: R230]
NOISE, VIBRATION AND HARSHNESS
(NVH) TROUBLESHOOTING
SYMPTOM DIAGNOSIS
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting ChartINFOID:0000000005148928
Use the chart below to help you find the cause of the sy mptom. If necessary, repair or replace these parts.
×: ApplicableReference page
DLN-253, "
Disassembly and Assembly
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DLN-253, "
Disassembly and Assembly
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DLN-253, "
Disassembly and Assembly
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DLN-270, "
Inspection and Adjustment
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DLN-270, "
Inspection and Adjustment
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MA-13, "
Fluids and Lubricants
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DLN-194, "
NVH Troubleshooting Chart
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RAX-5, "
NVH Troubleshooting Chart
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RSU-5, "
NVH Troubleshooting Chart
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WT-43, "
NVH Troubleshooting Chart
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WT-43, "
NVH Troubleshooting Chart
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RAX-5, "
NVH Troubleshooting Chart
"
BR-6, "
NVH Troubleshooting Chart
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ST-12, "
NVH Troubleshooting Chart
"
Possible cause and SUSPECTED PARTS
Gear tooth rough
Gear contact improper
Tooth surfaces worn
Backlash incorrect
Companion flange excessive runout
Gear oil improper
PROPELLER SHAFT
REAR AXLE
REAR SUSPENSION
TIRES
ROAD WHEEL
DRIVE SHAFT
BRAKES
STEERING
Symptom
Noise××××××× ××××××
Revision: April 20092010 QX56

EC-5
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P1140, P1145 IVT CONTROL POSITION
SENSOR ......................................................... ..
295
Component Description ....................................... ..295
On Board Diagnosis Logic ....................................295
DTC Confirmation Procedure ................................295
Diagnosis Procedure .............................................295
Component Inspection ..........................................298
P1148, P1168 CLOSED LOOP CONTROL .....299
On Board Diagnosis Logic .................................. ..299
P1211 TCS CONTROL UNIT ...........................300
Description .......................................................... ..300
On Board Diagnosis Logic ....................................300
DTC Confirmation Procedure ................................300
Diagnosis Procedure .............................................300
P1212 TCS COMMUNICATION LINE ..............301
Description .......................................................... ..301
On Board Diagnosis Logic ....................................301
DTC Confirmation Procedure ................................301
Diagnosis Procedure .............................................301
P1217 ENGINE OVER TEMPERATURE .........302
On Board Diagnosis Logic .................................. ..302
Overall Function Check .........................................302
Diagnosis Procedure .............................................303
Main 13 Causes of Overheating ............................304
P1225 TP SENSOR ..........................................306
Component Description ....................................... ..306
On Board Diagnosis Logic ....................................306
DTC Confirmation Procedure ................................306
Diagnosis Procedure .............................................306
P1226 TP SENSOR ..........................................308
Component Description ....................................... ..308
On Board Diagnosis Logic ....................................308
DTC Confirmation Procedure ................................308
Diagnosis Procedure .............................................308
P1421 COLD START CONTROL .....................310
Description .......................................................... ..310
On Board Diagnosis Logic ....................................310
DTC Confirmation Procedure ................................310
Diagnosis Procedure .............................................310
P1550 BATTERY CURRENT SENSOR ...........312
Component Description ....................................... ..312
On Board Diagnosis Logic ....................................312
DTC Confirmation Procedure ................................312
Diagnosis Procedure .............................................312
Component Inspection ..........................................314
P1551, P1552 BATTERY CURRENT SEN-
SOR ..................................................................
316
Component Description ....................................... ..316
On Board Diagnosis Logic ....................................316
DTC Confirmation Procedure ................................316
Diagnosis Procedure .............................................316
Component Inspection ..........................................318
P1553 BATTERY CURRENT SENSOR ..........320
Component Description ....................................... ..320
On Board Diagnosis Logic .....................................320
DTC Confirmation Procedure ................................320
Diagnosis Procedure .............................................320
Component Inspection ...........................................322
P1554 BATTERY CURRENT SENSOR ..........324
Component Description .........................................324
On Board Diagnosis Logic .....................................324
Overall Function Check .........................................324
Diagnosis Procedure .............................................325
Component Inspection ...........................................326
P1564 ICC STEERING SWITCH .....................328
Component Description .........................................328
On Board Diagnosis Logic .....................................328
DTC Confirmation Procedure ................................328
Diagnosis Procedure .............................................328
Component Inspection ...........................................330
P1564 ASCD STEERING SWITCH .................332
Component Description .........................................332
On Board Diagnosis Logic .....................................332
DTC Confirmation Procedure ................................332
Diagnosis Procedure .............................................332
Component Inspection ...........................................334
P1568 ICC FUNCTION ....................................336
On Board Diagnosis Logic .....................................336
DTC Confirmation Procedure ................................336
Diagnosis Procedure .............................................336
P1572 ICC BRAKE SWITCH ..........................337
Component Description .........................................337
On Board Diagnosis Logic .....................................337
DTC Confirmation Procedure ................................337
Diagnosis Procedure .............................................338
Component Inspection ...........................................343
P1572 ASCD BRAKE SWITCH ......................344
Component Description .........................................344
On Board Diagnosis Logic .....................................344
DTC Confirmation Procedure ................................344
Diagnosis Procedure .............................................345
Component Inspection ...........................................348
P1574 ICC VEHICLE SPEED SENSOR .........349
Component Description .........................................349
On Board Diagnosis Logic .....................................349
DTC Confirmation Procedure ................................349
Diagnosis Procedure .............................................349
P1574 ASCD VEHICLE SPEED SENSOR .....351
Component Description .........................................351
On Board Diagnosis Logic .....................................351
DTC Confirmation Procedure ................................351
Diagnosis Procedure .............................................351
P1805 BRAKE SWITCH .................................353
Description .............................................................353
Revision: April 20092010 QX56

INSPECTION AND ADJUSTMENTEC-13
< BASIC INSPECTION > [VK56DE]
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INSPECTION AND ADJUSTMENT
Basic InspectionINFOID:0000000005149055
1.INSPECTION START
1. Check service records for any recent repairs that may indicate a related malfunction, or a current need for scheduled maintenance.
2. Open engine hood and check the following:
- Harness connectors for improper connections
- Wiring harness for improper connections, pinches and cut
- Vacuum hoses for splits, kinks and improper connections
- Hoses and ducts for leaks
- Air cleaner clogging
- Gasket
3. Confirm that electrical or mechanical loads are not applied.
- Headlamp switch is OFF.
- Air conditioner switch is OFF.
- Rear window defogger switch is OFF.
- Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.
5. Run engine at about 2,000 rpm for about 2 minutes under no load.
6. Make sure that no DTC is displayed with CONSULT-III or GST.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnostic Procedure.
>> GO TO 3.
3.CHECK TARGET IDLE SPEED
With CONSULT-III
1. Run engine at about 2,000 rpm for about 2 minutes under no load.
SEF983U
SEF976U
SEF977U
Revision: April 20092010 QX56

EC-18
< BASIC INSPECTION >[VK56DE]
INSPECTION AND ADJUSTMENT
With CONSULT-III
1. Check the VIN of the vehicle and note it. Refer to
GI-20, "Model Variation".
2. Turn ignition switch ON and engine stopped.
3. Select “VIN REGISTRATION ” in “WORK SUPPORT” mode.
4. Follow the instruction of CONSULT-III display.
Accelerator Pedal Released Position LearningINFOID:0000000005149059
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal positi on sensor output signal. It must be performed each time
harness connector of accelerator pedal pos ition sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF and wait at least 10 seconds.
Throttle Valve Closed Position LearningINFOID:0000000005149060
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to l earn the fully closed position of the throttle valve by
monitoring the throttle position sensor output signal . It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF wait at least 10 seconds. Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningINFOID:0000000005149061
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific
range. It must be performed under any of the following conditions:
• Each time electric throttle control actuator or ECM is replaced.
• Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the follo wing conditions are missed for even a moment.
• Battery voltage: More than 12.9V (At idle)
• Engine coolant temperature: 70 - 100 °C (158 - 212° F)
• Select lever: P or N
• Electric load switch: OFF (Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
start the headlamp will not be illuminated.
• Steering wheel: Neutral (Straight-ahead position)
• Vehicle speed: Stopped
• Transmission: Warmed-up
- With CONSULT-III: Drive vehicle until “ATF TEMP SE 1” in “DATA MONITOR” mode of “A/T” system indi- cates less than 0.9V.
- Without CONSULT-III: Drive vehicle for 10 minutes.
OPERATION PROCEDURE
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

EC-26
< FUNCTION DIAGNOSIS >[VK56DE]
ENGINE CONTROL SYSTEM
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) : Vehicle front
BBIA0384E
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-32
< FUNCTION DIAGNOSIS >[VK56DE]
AIR CONDITIONING CUT CONTROL
AIR CONDITIONING CUT CONTROL
Input/Output Signal ChartINFOID:0000000005149066
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
System DescriptionINFOID:0000000005149067
This system improves engine operati
on when the air conditioner is used.
Under the following conditions, the air conditioner is turned OFF.
• When the accelerator pedal is fully depressed.
• When cranking the engine.
• At high engine speeds.
• When the engine coolant temperat ure becomes excessively high.
• When operating power steering during low engine speed or low vehicle speed.
• When engine speed is excessively low.
• When refrigerant pressure is excessively low or high.
Sensor Input Signal to ECMECM functionActuator
Air conditioner switch Air conditioner ON signal*
1
Air conditioner
cut controlAir conditio
ner relay
Accelerator pedal position sensor
Accelerator pedal position
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
2
Engine coolant temperature sensor
Engine coolant temperature
Battery Battery voltage*
2
Refrigerant pressure sensorRefrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensor Vehicle speed*
1
Revision: April 20092010 QX56