2008 INFINITI QX56 brake

PROPELLER SHAFTDLN-195
< REMOVAL AND INSTALLATION > [PROPELLER SHAFT: 2S1410]
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4WD
REMOVAL
1. Move the A/T select lever to the N position and release the parking brake.
2. Put matching marks on the rear propeller shaft flange yoke and the rear final drive companion flange as shown.
CAUTION:
For matching marks, use paint. Never damage the rear pro-
peller shaft flange yoke or the companion flange.
3. Remove the bolts, then remove the propeller shaft from the rear final drive and A/T or transfer.
INSPECTION
• Inspect the propeller shaft runout. If runout exceeds the limit, replace the propeller shaft assembly.
AWDIA0031ZZ
1. Propeller shaft tube 2. Snap ring3. Journal bearing
4. Sleeve yoke 5. Journal6. Flange yoke
⇐ : Front
WDIA0049E
Limit
Propeller shaft run out : Refer to DLN-199, "
Gen-
eral Specification"
LDIA0121E
Revision: March 2010 2008 QX56

DLN-206
< SYMPTOM DIAGNOSIS >[FRONT FINAL DRIVE: M205]
NOISE, VIBRATION AND HARSHNESS
(NVH) TROUBLESHOOTING
SYMPTOM DIAGNOSIS
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting ChartINFOID:0000000001604442
Use the chart below to help you find the cause of the sy mptom. If necessary, repair or replace these parts.
×: ApplicableReference page
DLN-214, "
Disassembly and Assembly
"
DLN-214, "
Disassembly and Assembly
"
DLN-214, "
Disassembly and Assembly
"
DLN-214, "
Disassembly and Assembly
"
DLN-214, "
Disassembly and Assembly
"
DLN-207, "
Changing Differential Gear Oil
"
DLN-182, "
NVH Troubleshooting Chart
"
FAX-5, "
NVH Troubleshooting Chart
"
FSU-6, "
NVH Troubleshooting Chart
"
WT-41, "
NVH Troubleshooting Chart
"
WT-41, "
NVH Troubleshooting Chart
"
FAX-5, "
NVH Troubleshooting Chart
"
BR-6, "
NVH Troubleshooting Chart
"
ST-12, "
NVH Troubleshooting Chart
"
Possible cause and SUSPECTED PARTS
Gear tooth rough
Gear contact improper
Tooth surfaces worn
Incorrect backlash
Companion flange excessive runout
Gear oil improper
PROPELLER SHAFT
FRONT AXLE
FRONT SUSPENSION
TIRES
ROAD WHEEL
DRIVE SHAFT
BRAKES
STEERING
Symptom
Noise××××××××××××××
Revision: March 2010 2008 QX56

DLN-240
< SYMPTOM DIAGNOSIS >[REAR FINAL DRIVE: R230]
NOISE, VIBRATION AND HARSHNESS
(NVH) TROUBLESHOOTING
SYMPTOM DIAGNOSIS
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting ChartINFOID:0000000001604455
Use the chart below to help you find the cause of the sy mptom. If necessary, repair or replace these parts.
×: ApplicableReference page
DLN-251, "
Disassembly and Assembly
"
DLN-251, "
Disassembly and Assembly
"
DLN-251, "
Disassembly and Assembly
"
DLN-268, "
Inspection and Adjustment
"
DLN-268, "
Inspection and Adjustment
"
MA-12, "
Fluids and Lubricants
"
DLN-192, "
NVH Troubleshooting Chart
"
DLN-240, "
NVH Troubleshooting Chart
"
RSU-5, "
NVH Troubleshooting Chart
"
WT-41, "
NVH Troubleshooting Chart
"
WT-41, "
NVH Troubleshooting Chart
"
RAX-5, "
NVH Troubleshooting Chart
"
BR-6, "
NVH Troubleshooting Chart
"
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: March 2010 2008 QX56

EC-5
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P1148, P1168 CLOSED LOOP CONTROL ... ..303
On Board Diagnosis Logic .................................. ..303
P1211 TCS CONTROL UNIT ...........................304
Description .......................................................... ..304
On Board Diagnosis Logic ....................................304
DTC Confirmation Procedure ................................304
Diagnosis Procedure .............................................304
P1212 TCS COMMUNICATION LINE ..............305
Description .......................................................... ..305
On Board Diagnosis Logic ....................................305
DTC Confirmation Procedure ................................305
Diagnosis Procedure .............................................305
P1217 ENGINE OVER TEMPERATURE .........306
On Board Diagnosis Logic .................................. ..306
Overall Function Check .........................................306
Diagnosis Procedure .............................................307
Main 13 Causes of Overheating ............................308
P1225 TP SENSOR ..........................................310
Component Description ....................................... ..310
On Board Diagnosis Logic ....................................310
DTC Confirmation Procedure ................................310
Diagnosis Procedure .............................................310
P1226 TP SENSOR ..........................................312
Component Description ....................................... ..312
On Board Diagnosis Logic ....................................312
DTC Confirmation Procedure ................................312
Diagnosis Procedure .............................................312
P1421 COLD START CONTROL .....................314
Description .......................................................... ..314
On Board Diagnosis Logic ....................................314
DTC Confirmation Procedure ................................314
Diagnosis Procedure .............................................314
P1550 BATTERY CURRENT SENSOR ...........316
Component Description ....................................... ..316
On Board Diagnosis Logic ....................................316
DTC Confirmation Procedure ................................316
Diagnosis Procedure .............................................316
Component Inspection ..........................................318
P1551, P1552 BATTERY CURRENT SEN-
SOR ..................................................................
320
Component Description ....................................... ..320
On Board Diagnosis Logic ....................................320
DTC Confirmation Procedure ................................320
Diagnosis Procedure .............................................320
Component Inspection ..........................................322
P1553 BATTERY CURRENT SENSOR ...........324
Component Description ....................................... ..324
On Board Diagnosis Logic ....................................324
DTC Confirmation Procedure ................................324
Diagnosis Procedure .............................................324
Component Inspection ..........................................326
P1554 BATTERY CURRENT SENSOR ..........328
Component Description ....................................... ..328
On Board Diagnosis Logic .....................................328
Overall Function Check .........................................328
Diagnosis Procedure .............................................329
Component Inspection ...........................................330
P1564 ICC STEERING SWITCH .....................332
Component Description .........................................332
On Board Diagnosis Logic .....................................332
DTC Confirmation Procedure ................................332
Diagnosis Procedure .............................................332
Component Inspection ...........................................335
P1564 ASCD STEERING SWITCH .................336
Component Description .........................................336
On Board Diagnosis Logic .....................................336
DTC Confirmation Procedure ................................336
Diagnosis Procedure .............................................336
Component Inspection ...........................................338
P1568 ICC FUNCTION ....................................340
On Board Diagnosis Logic .....................................340
DTC Confirmation Procedure ................................340
Diagnosis Procedure .............................................340
P1572 ICC BRAKE SWITCH ..........................341
Component Description .........................................341
On Board Diagnosis Logic .....................................341
DTC Confirmation Procedure ................................341
Diagnosis Procedure .............................................342
Component Inspection ...........................................346
P1572 ASCD BRAKE SWITCH ......................347
Component Description .........................................347
On Board Diagnosis Logic .....................................347
DTC Confirmation Procedure ................................347
Diagnosis Procedure .............................................348
Component Inspection ...........................................351
P1574 ICC VEHICLE SPEED SENSOR .........352
Component Description .........................................352
On Board Diagnosis Logic .....................................352
DTC Confirmation Procedure ................................352
Diagnosis Procedure .............................................352
P1574 ASCD VEHICLE SPEED SENSOR .....354
Component Description .........................................354
On Board Diagnosis Logic .....................................354
DTC Confirmation Procedure ................................354
Diagnosis Procedure .............................................354
P1805 BRAKE SWITCH .................................356
Description .............................................................356
On Board Diagnosis Logic .....................................356
DTC Confirmation Procedure ................................356
Diagnosis Procedure .............................................356
Component Inspection ...........................................358
P2100, P2103 THROTTLE CONTROL MO-
TOR RELAY ....................................................
359
Revision: March 2010 2008 QX56

EC-6
Component Description .........................................359
On Board Diagnosis Logic .....................................359
DTC Confirmation Procedure ................................359
Diagnosis Procedure .............................................360
P2101 ELECTRIC THROTTLE CONTROL
FUNCTION .......................................................
362
Description ........................................................... ..362
On Board Diagnosis Logic .....................................362
DTC Confirmation Procedure ................................362
Diagnosis Procedure .............................................362
Component Inspection ...........................................365
P2118 THROTTLE CONTROL MOTOR ..........366
Component Description ....................................... ..366
On Board Diagnosis Logic .....................................366
DTC Confirmation Procedure ................................366
Diagnosis Procedure .............................................366
Component Inspection ...........................................367
P2119 ELECTRIC THROTTLE CONTROL
ACTUATOR .....................................................
368
Component Description ....................................... ..368
On Board Diagnosis Logic .....................................368
DTC Confirmation Procedure ................................368
Diagnosis Procedure .............................................369
P2122, P2123 APP SENSOR ..........................370
Component Description ....................................... ..370
On Board Diagnosis Logic .....................................370
DTC Confirmation Procedure ................................370
Diagnosis Procedure .............................................371
Component Inspection ...........................................372
P2127, P2128 APP SENSOR ..........................373
Component Description ....................................... ..373
On Board Diagnosis Logic .....................................373
DTC Confirmation Procedure ................................373
Diagnosis Procedure .............................................373
Component Inspection ...........................................376
P2135 TP SENSOR .........................................377
Component Description ....................................... ..377
On Board Diagnosis Logic .....................................377
DTC Confirmation Procedure ................................377
Diagnosis Procedure .............................................377
Component Inspection ...........................................380
P2138 APP SENSOR ......................................381
Component Description ....................................... ..381
On Board Diagnosis Logic .....................................381
DTC Confirmation Procedure ................................381
Diagnosis Procedure .............................................382
Component Inspection ...........................................384
P2A00, P2A03 A/F SENSOR 1 .......................385
Component Description ....................................... ..385
On Board Diagnosis Logic .....................................385
DTC Confirmation Procedure ................................385
Diagnosis Procedure .............................................386
ASCD BRAKE SWITCH ...................................390
Component Description ....................................... .390
Diagnosis Procedure .............................................390
Component Inspection ..........................................393
ASCD INDICATOR ...........................................394
Component Description ....................................... .394
Diagnosis Procedure .............................................394
COOLING FAN .................................................395
Diagnosis Procedure ............................................ .395
Component Inspection ..........................................395
ELECTRICAL LOAD SIGNAL ..........................397
Description ........................................................... .397
Diagnosis Procedure .............................................397
FUEL INJECTOR ..............................................399
Component Description ....................................... .399
Diagnosis Procedure .............................................399
Component Inspection ..........................................401
FUEL PUMP .....................................................402
Description ........................................................... .402
Diagnosis Procedure .............................................402
Component Inspection ..........................................405
ICC BRAKE SWITCH ..................................... ..406
Component Description ....................................... .406
Diagnosis Procedure .............................................406
Component Inspection ..........................................409
IGNITION SIGNAL ............................................411
Component Description ....................................... .411
Diagnosis Procedure .............................................411
Component Inspection ..........................................414
ON BOARD REFUELING VAPOR RECOV-
ERY (ORVR) .....................................................
416
System Description .............................................. .416
Diagnosis Procedure .............................................416
Component Inspection ..........................................418
POSITIVE CRANKCASE VENTILATION .........421
Description ........................................................... .421
Component Inspection ..........................................421
REFRIGERANT PRESSURE SENSOR ...........423
Component Description ....................................... .423
Diagnosis Procedure .............................................423
ECU DIAGNOSIS ......................................426
ECM ................................................................ ..426
CONSULT-lll Reference Value in Data Monitor
Mode .................................................................... .
426
ECM Harness Connector Terminal Layout ...........429
ECM Terminal and Reference Value ....................429
Wiring Diagram - ENGINE CONTROL SYSTEM - .439
Fail-Safe Chart ......................................................459
DTC Inspection Priority Chart ...............................461
Revision: March 2010 2008 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:0000000001351333
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:0000000001351334
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:0000000001351335
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)
• Selector 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: March 2010 2008 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: March 2010 2008 QX56

AUTOMATIC SPEED CONTROL DEVICE (ASCD)EC-33
< FUNCTION DIAGNOSIS > [VK56DE]
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AUTOMATIC SPEED CONTROL DEVICE (ASCD)
System DescriptionINFOID:0000000001351238
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line
BASIC ASCD SYSTEM
Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set
vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric thro ttle control actuator to regulate engine speed.
Operation status of ASCD is indicated by CRUISE i ndicator and SET indicator in combination meter. If any
malfunction occurs in ASCD system, it automatically deactivates control.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.
SET OPERATION
Press MAIN switch. (The CRUISE indicato r in combination meter illuminates.)
When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET indicator in combination meter illuminates.)
ACCELERATE OPERATION
If the RESUME/ACCELERATE switch is pressed during cr uise control driving, increase the vehicle speed until
the switch is released or vehicle speed reac hes maximum speed controlled by the system.
And then ASCD will keep the new set speed.
CANCEL OPERATION
When any of following conditions exis t, cruise operation will be canceled.
• CANCEL switch is pressed
• More than 2 switches at ASCD steer ing switch are pressed at the same time (Set speed will be cleared)
• Brake pedal is depressed
• Selector lever is changed to N, P, R position
• Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
• VDC system is operated
When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform
the driver by blinking indicator lamp.
• Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE lamp may
blink slowly.
When the engine coolant temperature decreases to t he normal operating temperature, CRUISE lamp will
stop blinking and the cruise operation will be able to work by pressing SET/COAST switch or RESUME/
ACCELERATE switch.
• Malfunction for some self-diagnoses regarding ASCD control: SET lamp will blink quickly.
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
COAST OPERATION
When the SET/COAST switch is pressed during cruise control driving, decrease vehicle set speed until the
switch is released. And then ASCD will keep the new set speed.
RESUME OPERATION
Sensor Input signal to ECM ECM functionActuator
ASCD brake switch Brake pedal operation
ASCD vehicle speed controlElectric throttle control
actuator
Stop lamp switch
Brake pedal operation
ASCD steering switch ASCD steering switch operation
Wheel sensor Vehicle speed*
TCM Powertrain revolution*
Gear position
Revision: March 2010
2008 QX56