change wheel INFINITI QX4 2005 Factory Service Manual

A/T CONTROL SYSTEM
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Engine Brake ControlECS00CE2

The forward one-way clutch transmits the drive force from the engine to the rear wheels. But the reverse
drive from the rear wheels is not transmitted to the engine because the one-way clutch is idling.
Therefore, the low coast brake solenoid is operated to prevent the forward one-way clutch from idling and
the engine brake is operated in the same manner as conventionally.

The operation of the low coast brake solenoid switches the low coast brake switching valve and controls
the coupling and releasing of the low coast brake.
The low coast brake reducing valve controls the low coast brake coupling force.
Control ValveECS00CE3
FUNCTION OF CONTROL VALVE
SCIA1520E
Name Function
Torque converter regulator valveIn order to prevent the pressure supplied to the torque converter from being excessive,
the line pressure is adjusted to the optimum pressure (torque converter operating pres-
sure).
Pressure regulator valve
Pressure regulator plug
Pressure regulator sleeveAdjusts the oil discharged from the oil pump to the optimum pressure (line pressure) for
the driving state.
Front brake control valveWhen the front brake is coupled, adjusts the line pressure to the optimum pressure
(front brake pressure) and supplies it to the front brake. (In 1st, 2nd, 3rd, and 5th gears,
adjusts the clutch pressure.)
Accumulator control valveAdjusts the pressure (accumulator control pressure) acting on the accumulator piston
and low coast reducing valve to the pressure appropriate to the driving state.
Pilot valve AAdjusts the line pressure and produces the constant pressure (pilot pressure) required
for line pressure control, shift change control, and lock-up control.
Pilot valve BAdjusts the line pressure and produces the constant pressure (pilot pressure) required
for shift change control.
Low coast brake switching valve During engine braking, supplies the line pressure to the low coast brake reducing valve.
Low coast brake reducing valveWhen the low coast brake is coupled, adjusts the line pressure to the optimum pressure
(low coast brake pressure) and supplies it to the low coast brake.
N-R accumulator Produces the stabilizing pressure for when N-R is selected.
Direct clutch piston switching valve Operates in 4th gear and switches the direct clutch coupling capacity.
High and low reverse clutch control valveWhen the high and low reverse clutch is coupled, adjusts the line pressure to the opti-
mum pressure (high and low reverse clutch pressure) and supplies it to the high and low
reverse clutch. (In 1st, 3rd, 4th and 5th gears, adjusts the clutch pressure.)

AUDIO
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System DescriptionEKS00BI8
Refer to Owner's Manual for audio system operating instructions.
Power is supplied at all times

through 15A fuse [No. 17, located in the fuse block (J/B)]

to subwoofer terminal 6

through 20A fuse [No. 31, located in the fuse and fusible link box]

to audio unit terminal 6

to BOSE speaker amp. terminal 1

to AV switch terminal 1 and

to display control unit terminal 1.
With the ignition switch in the ACC or ON position, power is supplied

through 10A fuse [No. 4, located in the fuse block (J/B)]

to audio unit terminal 10 and

to AV switch terminal 2 and

to display control unit terminal 10.
With the ignition switch in the ON or START position, power is supplied

through 10A fuse [No. 12, located in the fuse block (J/B)]

to display control unit terminal 12.
Ground is supplied through the case of the audio unit.
Ground is also supplied

to subwoofer terminal 5

through body grounds B7 and B19 and

to BOSE speaker amp. terminal 17

to AV switch terminal 5 and

to display unit terminal 1 and

to display control unit terminal 3

through body grounds M57, M61 and M79.
Then audio signals are supplied

through audio unit terminals 1, 2, 3, 4, 13, 14, 15 and 16

to BOSE speaker amp. terminals 23, 24, 25, 26, 27, 28, 29 and 30.
Audio signals are amplified by the BOSE speaker amp.
The amplified audio signals are supplied

through BOSE speaker amp. terminals 2, 3, 9,10,11,12, 13, 14, 15, 16, 18 and 19

to terminals + and - of front door speaker LH and RH and

to terminals + and - of front tweeter LH and RH and

to terminals + and - of center speaker and

to terminals + and - of rear door speaker LH and RH and

to terminals + and - of rear door tweeter LH and RH and

to terminals 1 and 2 of subwoofer.
When one of steering wheel audio control switches is pushed, the resistance in steering switch circuit changes
depending on which button is pushed.
REAR AUDIO REMOTE CONTROL UNIT
Power is supplied

from audio unit terminal 32

to rear audio remote control unit terminal 13.
Ground is supplied

to rear audio remote control unit terminal 15

through body grounds B117 and B132.
Audio signals are supplied

AUDIO
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Terminals and Reference Value for AV SwitchEKS00BIE
Te r m i n a l N o .
(Wire color)
ItemSignal
input/
outputCondition
Voltag e
(Approx.)Example of
symptom
+–Ignition
switchOperation
1 (Y) GroundBattery
powerInput OFF – Battery voltageSystem does not
work properly.
2 (V) Ground ACC signal Input ACC – Battery voltageSystem does not
work properly.
3 (R/L) GroundIllumination
signalInput OFFLighting switch is
ON (position 1).Battery voltageAV switch illumi-
nation does not
come on when
lighting switch is
ON (position 1). Turn lighting switch
OFF.Approx. 3.0V or less
4 (BR) GroundIllumination
control signalInput ONIllumination control
switch is operated
by lighting switch in
1st position.Changes between 0 and 12V.AV switch illumi-
nation cannot be
controlled.
5 (B) Ground Ground – ON – 0V –
6 (V) GroundCommunica-
tion signal (+)Input/
outputON –System does not
work properly.
7–Shield
ground–– – –
8 (LG) GroundCommunica-
tion signal (-)Input/
outputON –System does not
work properly.
12 (R) GroundRemote con-
trol AInput ONPress MODE
switch 0V
Steering wheel
audio controls
do not function. Press SEEK UP
switch0.75V
Press VOL UP
switch2V
Except for above 5V
13 (G) GroundRemote con-
trol BInput ONPress POWER
switch 0V
Steering wheel
audio controls
do not function. Press SEEK
DOWN switch0.75V
Press VOL DOWN
switch2V
Except for above 5V
14 (L) –Remote con-
trol ground–– – –Steering wheel
audio controls
do not function.
16 (W/B) GroundCD EJECT
signalOutput ONPressed 0V
CD eject does
not function.
Released 5V
SKIA0175E
SKIA0176E

AV-62
NAVIGATION SYSTEM
Revision: October 20052005 QX56

In map-matching, alternative routes to reach the destination will
be shown and prioritized, after the road on which the vehicle is
currently driven has been judged and the current-location mark
has been repositioned.
If there is an error in distance and/or direction, the alternative
routes will be shown in different order of priority, and the wrong
road can be avoided.
If two roads are running in parallel, they are of the same priority.
Therefore, the current-location mark may appear on either of
them alternately, depending on maneuvering of the steering
wheel and configuration of the road.

Map-matching does not function correctly when the road on
which the vehicle is driving is new and not recorded in the map
DVD-ROM, or when the road pattern stored in the map data and
the actual road pattern are different due to repair.
When driving on a road not present in the map, the map-match-
ing function may find another road and position the current-loca-
tion mark on it. Then, when the correct road is detected, the
current-location mark may leap to it.

Effective range for comparing the vehicle position and travel
direction calculated by the distance and direction with the road
data read from the map DVD-ROM is limited. Therefore, when
there is an excessive gap between the current vehicle position
and the position on the map, correction by map-matching is not possible.
GPS (GLOBAL POSITIONING SYSTEM)
GPS (Global Positioning System) has been developed and con-
trolled by the US Department of Defense. The system utilizes GPS
satellite (NAVSTAR), sending out radio waves while flying on an orbit
around the earth at the height of approx. 21,000 km (13,000 miles).
The GPS receiver calculates the vehicle's position in three dimen-
sions (latitude/longitude/altitude) according to the time lag of the
radio waves received from four or more GPS satellites (three-dimen-
sional positioning). If radio waves were received only from three
GPS satellites, the GPS receiver calculates the vehicle's position in
two dimensions (latitude/longitude), utilizing the altitude data calcu-
lated previously by using radio waves from four or more GPS satel-
lites (two-dimensional positioning).
Accuracy of the GPS will deteriorate under the following conditions.

In two-dimensional positioning, the GPS accuracy will deteriorate when the altitude of the vehicle position
changes.

There may be an error of approximately 10 m (30 ft) in position detected by three-dimensional positioning,
which is more accurate than two-dimensional positioning. The accuracy can be even lower depending on
the arrangement of the GPS satellites utilized for the positioning.

Position detection is not possible when the vehicle is in an area where radio waves from the GPS satellite
do not reach, such as in a tunnel, parking lot in a building, and under an elevated highway. Radio waves
from the GPS satellites may not be received when some object is located over the GPS antenna.

Position correction by GPS is not available while the vehicle is stopped.
SEL686V
SKIA0613E
SEL526V

AV-98
NAVIGATION SYSTEM
Revision: October 20052005 QX56
Terminals and Reference Value for AV SwitchEKS00BJN
Te r m i n a l N o .
(Wire color)
ItemSignal
input/
outputCondition
Voltage
(Approx.)Example of
symptom
+–Ignition
switchOperation
1 (Y) GroundBattery
powerInput OFF - Battery voltageSystem does not
work properly.
2 (V) Ground ACC signal Input ACC - Battery voltageSystem does not
work properly.
3 (R/L) GroundIllumination
signalInput OFFLighting switch is
ON (position 1).Battery voltageAV switch illumi-
nation does not
come on when
lighting switch is
ON (position 1). Turn lighting switch
OFF.3.0V or less
4 (BR) GroundIllumination
control signalInput ONIllumination control
switch is operated
by lighting switch in
1st position.Changes between 0 and 12V.AV switch illumi-
nation cannot be
controlled.
5 (B) Ground Ground - ON - 0V -
6 (V) GroundCommunica-
tion signal (+)Input/
outputON -System does not
work properly.
7-Shield
ground-- - - -
8 (LG) GroundCommunica-
tion signal (-)Input/
outputON -System does not
work properly.
12 (R) GroundRemote con-
trol AInput ONPress MODE
switch 0V
Steering wheel
audio controls
do not function. Press SEEK UP
switch0.75V
Press VOL UP
switch2V
Except for above 5V
13 (G) GroundRemote con-
trol BInput ONPress POWER
switch 0V
Steering wheel
audio controls
do not function. Press SEEK
DOWN switch0.75V
Press VOL DOWN
switch2V
Except for above 5V
14 (L) -Remote con-
trol ground-- - -Steering wheel
audio controls
do not function.
SKIA0175E
SKIA0176E

NAVIGATION SYSTEM
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On Board Self-Diagnosis FunctionEKS00BJP
DESCRIPTION

Diagnosis function consists of the self-diagnosis mode performed automatically and the CONFIRMATION/
ADJUSTMENT mode operated manually.

Self-diagnosis mode checks for connections between the units constituting this system, analyzes each
individual unit at the same time, and displays the results on the LCD screen.

CONFIRMATION/ADJUSTMENT mode is used to perform trouble diagnosis that require operation and
judgment by an operator (trouble that cannot be automatically judged by the system), to check/change the
set value, and to display the History of Errors of the navigation system.
DIAGNOSIS ITEM
NOTE:
Make the status that is set by D/N function be shown.
Self-Diagnosis Mode (DCU)EKS00BJQ
OPERATION PROCEDURE
1. Start the engine.
2. Turn the audio system off.
Mode Description
Self-diagnosis (DCU) Display control unit diagnosis.
Self-diagnosis (NAVI)

NAVI Control unit diagnosis (DVD-ROM drive) will not be diagnosed
when no map DVD-ROM is in it.

Analyzes connection between the NAVI control unit and the GPS
antenna and operation of each unit.
CONFIRMATION/
ADJUSTMENTDisplay diagnosisIn display control unit mode, color tone and shading of the screen can be
checked by the display of a color bar and a gray scale.
Vehicle signalsIn display control unit mode, analyzes the following vehicle signals: Vehi-
cle speed signal, light signal
NOTE , ignition switch signal, and reverse sig-
nal.
Auto Climate Control A/C self-diagnosis of A/C system.
NavigationDisplay diagnosisIn NAVI C/U mode, color tone and shading of the screen can be checked
by the display of a color bar and a gray scale.
Vehicle signalsIn NAVI C/U mode, analyzes the following vehicle signals: Vehicle speed
signal, light signal, ignition switch signal, and reverse signal.
History of ErrorsDiagnosis results previously stored in the memory (before turning ignition
switch ON) are displayed in this mode. Time and location when/where the
errors occurred are also displayed.
Naviga-
tionDisplay Lon-
gitude & Lat-
itudeDisplay the map. Use the joystick to adjust position. Longitude and latitude
will be displayed.
Speed Cali-
brationUnder ordinary conditions, the navigation system distance measuring
function will automatically compensate for minute decreases in wheel and
tire diameter caused by tire wear or low-pressure. Speed calibration imme-
diately restores system accuracy in cases such as when distance calibra-
tion is needed because of the use of tire chains in inclement weather.
Angle
adjustmentCorrects difference between actual turning angle of a vehicle and turning
angle of the car mark on the display.
Initialize
LocationThis mode is for initializing the current location. Use when the vehicle is
transported a long distance on a trailer, etc.
CAN DIAG SUPPORT MONITOR Display status of CAN communication.

NAVIGATION SYSTEM
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Revision: October 20052005 QX56
PlaceIn a parking lot When driving in a parking lot, or other loca-
tion where there are no roads on the map,
matching may place the vehicle mark on a
nearby road. When the vehicle returns to
the road, the vehicle mark may have devi-
ated from the correct location.
When driving in circle or turning the steer-
ing wheel repeatedly, direction errors accu-
mulate, and the vehicle mark may deviate
from the correct location.
If after travelling about 10 km (6
miles) the correct location has
not been restored, perform
location correction and, if nec-
essary, direction correction. Turntable
When the ignition switch is OFF, the navi-
gation system cannot get the signal from
the gyroscope (angular speed sensor).
Therefore, the displayed direction may be
wrong and the correct road may not be
easily returned to after rotating the vehicle
on a turntable with the ignition OFF.
Slippery roads On snow, wet roads, gravel, or other roads
where tires may slip easily, accumulated
mileage errors may cause the vehicle mark
to deviate from the correct road.
Slopes When parking in sloped garages, when
travelling on banked roads, or in other
cases where the vehicle turns when tilted,
an error in the turning angle will occur, and
the vehicle mark may deviate from the
road.
Map dataRoad not displayed on the map screen
When driving on new roads or other roads
not displayed on the map screen, map
matching does not function correctly and
matches the location to a nearby road.
When the vehicle returns to a road which is
on the map, the vehicle mark may deviate
from the correct road.
Different road pattern
(Changed due to repair)
If the road pattern stored in the map data
and the actual road pattern are different,
map matching does not function correctly
and matches the location to a nearby road.
The vehicle mark may deviate from the
correct road.
Vehicle Use of tire chainsWhen tire chains are used, the mileage is
not correctly detected, and the vehicle
mark may deviate from the correct road.Drive the vehicle for a while. If
the distance still deviates,
adjust it by using the distance
adjustment function. (If the tire
chain is removed, recover the
original value.) Cause (condition) –: While driving ooo: Display Driving condition Remarks (correction, etc.)
SEL709V
SEL710V
SEL699V
ELK0201D

NAVIGATION SYSTEM
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Revision: October 20052005 QX56
CURRENT LOCATION MARK IS IN A RIVER OR SEA
The navigation system moves the current-location mark with no distinction between land and rivers or sea. If
the location mark is somehow out of place, it may appear that the vehicle is driving in a river or the sea.
WHEN DRIVING ON SAME ROAD, SOMETIMES CURRENT-LOCATION MARK IS IN RIGHT
PLACE AND SOMETIMES IT IS WRONG PLACE
The conditions of the GPS antenna (GPS data) and gyroscope (angular speed sensor) change gradually.
Depending on the road traveled and the operation of the steering wheel, the location detection results will be
different. Therefore, even on a road on which the location has never been wrong, conditions may cause the
vehicle mark to deviate.
LOCATION CORRECTION BY MAP-MATCHING IS SLOW

The map-matching function needs to refer to the data of the surrounding area. It is necessary to drive
some distance for the function to work.

Because map-matching operates on this principle, when there are many roads running in similar direc-
tions in the surrounding area, no matching determination may be made. The location may not be cor-
rected until some special feature is found.
ALTHOUGH GPS RECEIVING DISPLAY IS GREEN, VEHICLE MARK DOES NOT RETURN TO
CORRECT LOCATION

The GPS accuracy has an error of approximately 10 m (30 ft). In some cases the current-location mark
may not be on the correct street, even when GPS location-correction is done.

The navigation system compares the results of GPS location detection with the results from map-match-
ing location detection. The one which is determined to have higher accuracy is used.

GPS location correction may not be performed when the vehicle is stopped.
NAME OF CURRENT PLACE IS NOT DISPLAYED
The current place name may not be displayed if there are no place names displayed on the map screen.
CONTENTS OF DISPLAY DIFFER FOR BIRDVIEW™ AND THE (FLAT) MAP SCREEN
Difference of the BIRDVIEW™ screen from the flat map screen are as follows.

The current place name displays names which are primarily in the direction of vehicle travel.

The amount of time before the vehicle travel or turn angle is updated on the screen is longer than for the
(flat) map display.

The conditions for display of place names, roads, and other data are different for nearby areas and for
more distant areas.

Some thinning of the character data is done to prevent the display becoming too complex. In some cases
and in some locations, the display contents may differ.

The same place name, street name, etc. may be displayed multiple times.

BRC-1
BRAKE CONTROL SYSTEM
F BRAKES
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SECTION BRC
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BRC
Revision: October 20052005 QX56VDC/TCS/ABS
PRECAUTIONS .......................................................... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Precautions for Brake System .................................. 3
Precautions When Using CONSULT-II ..................... 3
CHECK POINTS FOR USING CONSULT-II ......... 3
Precautions for Brake Control .................................. 4
Precautions for CAN System ................................... 4
Wiring Diagrams and Trouble Diagnosis .................. 5
PREPARATION ........................................................... 6
Special Service Tool ................................................. 6
Commercial Service Tools ........................................ 6
SYSTEM DESCRIPTION ............................................ 7
System Components ................................................ 7
ABS Function ........................................................... 8
EBD Function ........................................................... 8
TCS Function ........................................................... 8
VDC Function ........................................................... 8
Fail-Safe Function .................................................... 8
ABS/EBD SYSTEM ............................................... 9
VDC/TCS SYSTEM ............................................... 9
ACTIVE BOOSTER ............................................... 9
Hydraulic Circuit Diagram ........................................ 9
CAN COMMUNICATION .......................................... 10
System Description ................................................ 10
TROUBLE DIAGNOSIS .............................................11
How to Perform Trouble Diagnoses for Quick and
Accurate Repair ......................................................11
INTRODUCTION ..................................................11
WORK FLOW ...................................................... 12
CLARIFY CONCERN .......................................... 13
EXAMPLE OF DIAGNOSIS SHEET ................... 13
Component Parts and Harness Connector Location ... 14
Schematic .............................................................. 15
Wiring Diagram — VDC — ..................................... 16
Basic Inspection ..................................................... 23
BRAKE FLUID LEVEL, FLUID LEAK, AND
BRAKE PAD INSPECTION ................................. 23POWER SYSTEM TERMINAL LOOSENESS
AND BATTERY INSPECTION ............................. 23
ABS WARNING LAMP, SLIP INDICATOR LAMP
AND VDC OFF INDICATOR LAMP INSPECTION ... 23
Warning Lamp and Indicator Timing ....................... 24
Control Unit Input/Output Signal Standard ............. 24
REFERENCE VALUE FROM CONSULT-II ......... 24
CONSULT-II Function (ABS) .................................. 28
CONSULT-II BASIC OPERATION PROCEDURE
... 28
SELF-DIAGNOSIS .............................................. 29
DATA MONITOR ................................................. 32
ACTIVE TEST ..................................................... 36
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC
ITEMS ........................................................................ 38
Wheel Sensor System Inspection ........................... 38
Engine System Inspection ...................................... 39
ABS/TCS/VDC Control Unit Inspection .................. 40
Steering Angle Sensor System ............................... 41
Yaw Rate/Side/Decel G Sensor System Inspection ... 42
Solenoid and VDC Change-Over Valve System
Inspection ............................................................... 43
Actuator Motor, Motor Relay, and Circuit Inspection ... 44
Stop Lamp Switch System Inspection .................... 45
ABS/TCS/VDC Control Unit Power and Ground
Systems Inspection ................................................ 46
Brake Fluid Level Sensor System Inspection ......... 47
Active Booster System Inspection .......................... 49
Delta Stroke Sensor System Inspection ................. 50
Pressure Sensor System Inspection ...................... 51
Steering Angle Sensor Safe Mode Inspection ........ 54
CAN Communication System Inspection ................ 55
Inspection For Self-diagnosis Result "ST ANGLE
SEN SIGNAL" ......................................................... 55
Inspection For Self-diagnosis Result "DECEL G
SEN SET" ............................................................... 55
VDC OFF Indicator lamp Does Not Illuminate ........ 56
Component Inspection ............................................ 56
VDC OFF SWITCH ............................................. 56

EC-24Revision: October 2005
ENGINE CONTROL SYSTEM
2005 QX56
Multiport Fuel Injection (MFI) SystemUBS00KZ7
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). The 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 INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.
<Fuel increase>

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
<Fuel decrease>

During deceleration

During high engine speed operation
Sensor Input signal to ECM ECM function Actuator
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
Park/neutral position (PNP) switch Gear position
Knock sensor Engine knocking condition
Battery
Battery voltage*
3
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit)*
2VDC/TCS operation command
Air conditioner switch*
2Air conditioner operation
Wheel sensor*
2Vehicle speed