4WD INFINITI QX56 2011 Factory Owners Manual

DLN-10
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
COMPONENT PARTS
SYSTEM DESCRIPTION
COMPONENT PARTS
Component Parts LocationINFOID:0000000006222214
1. ECM
Refer to EC-16, "
Component Parts
Location". 2. ABS actuator and electric unit (con-
trol unit)
Refer to BRC-10, "Component Parts
Location". 3. Steering angle sensor
Refer to BRC-10, "
Component Parts
Location".
4. Control valve & TCM Refer to TM-10, "
A/T CONTROL
SYSTEM : Compon ent Parts Loca-
tion". 5. Transfer control unit 6. 4WD switch assembly
7. Transfer lock position sensor 8. Transfer Hi-Lo position sensor 9. Transfer rotary position sensor
10. Transfer control actuator 11. Transfer fluid temperature sensor
A. Back of glove box assembly B. 4WD indicator lamp, 4WD warning lamp, ATP warning lamp (in combina-
tion meter)C. Console assembly
D. Transfer assembly upper side E. Transfer assembly under side
JPDIE0270GB
Revision: 2010 May2011 QX56

COMPONENT PARTSDLN-11
< SYSTEM DESCRIPTION > [TRANSFER: ATX90A]
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Component DescriptionINFOID:0000000006222215
Transfer Control UnitINFOID:0000000006222216
 Transfer control unit operates transfer control act uator, 4WD warning lamp and 4WD mode indicator lamp
according to input signal from 4WD shift switch and each sensor and control unit.
 When 4WD system is malfunctioning, 4WD warning la mp turns ON and fail-safe status activates.
 When protection is necessary, 4WD warning la mp blinks and protection status activates.
Transfer Control ActuatorINFOID:0000000006222217
Transfer control actuator integrates transfer motor, transfer internal position sensor, and transfer motor tem-
perature sensor, and switches 4WD mode (AUTO ⇔4H ⇔4L).
TRANSFER MOTOR
Transfer motor operates according to signal from transfer control unit and switches 4WD mode
(AUTO ⇔4H ⇔4L). It also performs front and rear distri bution of traction force during AUTO mode.
TRANSFER INTERNAL SPEED SENSOR
Transfer internal speed sensor detects rotation status of transfer motor and transmits signal to transfer control
unit.
TRANSFER MOTOR TEMPERATURE SENSOR
 Transfer motor temperature sensor m easures temperature of transfer motor.
Component parts Reference/Function
Transfer control unit DLN-11, "
Transfer Control Unit"
Transfer control actua-
torTransfer motor
DLN-11, "
Transfer Control Actuator"
Transfer internal speed
sensorDLN-11, "Transfer Control Actuator"
Transfer motor temper-
ature sensor
DLN-11, "Transfer Control Actuator"
Transfer Hi-Lo position sensor
DLN-12, "Transfer Hi-Lo Position Sensor"
Transfer rotary position sensorDLN-12, "Transfer Rotary Position Sensor"
Transfer lock position sensorDLN-12, "Transfer Lock Position Sensor"
Transfer fluid temperature sensorDLN-12, "Transfer Fluid Temperature Sensor"
4WD mode switchDLN-18, "4WD SYSTEM : System Description"
4WD indicator lampDLN-18, "4WD SYSTEM : System Description"
4WD warning lampDLN-18, "4WD SYSTEM : System Description"
AT P w a r n i n g l a m pDLN-18, "4WD SYSTEM : System Description"
ABS actuator and electric unit (control unit)Transmits the following signals via CAN communication line to transfer control unit.
 Vehicle speed signal (ABS)
 Stop lamp switch signal (brake signal)
 ABS operation signal
 VDC operation signal
 TCS operation signal
Steering angle sensor Transmits the following signals via CAN communication line to transfer control unit.
 Steering angle sensor signal
ECM Transmits the following signals via CAN communication line to transfer control unit.
 Accelerator pedal position signal
 Engine speed signal
 Engine torque signal
TCM Transmits the following signals via CAN communication line to transfer control unit.
 Shift position signal
 Gear position signal
 Output shaft revolution signal
Revision: 2010 May2011 QX56

DLN-14
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
STRUCTURE AND OPERATION
DESCRIPTION
 Ball ramp lever operates in the direction of main shaft axis according to rotation of actuator shaft and
presses piston. Pressure is applied to each clutch and torque is transmitted.
 Shift fork operates in the direction of main shaft axis according to rotation of actuator shaft and performs
engagement and disengagement to Hi-Lo sleeve and lock sleev e of main shaft. Mode is switched between
4H ⇔4L.
AUTO MODE
 The optimum torque distribution is electronically performed for front and rear wheels according to road con-
ditions.
 Stable start without wheel spin is possible on slippery road conditions, such as on a snowy road.
 When road condition does not require 4WD driving, the st atus becomes close to rear wheel drive, which
results in better fuel efficiency and prov ides FR-like steering characteristics.
 The vehicle cornering status is judged according to information from each sensor, and the optimum torque is
distributed to front wheels for prev enting tight-corner braking symptom.
NOTE:
When there is a difference of revolution speed between the front and rear wheel the shift occasionally changes
to direct 4-wheel driving conditions aut omatically. This is not a malfunction.
4H MODE
 Torque distribution for front and rear wheels is fixed and stable start is achieved while driving on an rough,
sandy or snowy road.
4L MODE
 Large traction force is obtained due to low gear. High running ability and escaping ability are achieved.
 Switching from 4H mode to 4L mode is not possible w hen the vehicle is not stopped and A/T shift selector is
not in the neutral position.
TORQUE DISTRIBUTION DIAGRAM
JPDIE0256GB
Revision: 2010 May2011 QX56

DLN-18
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
SYSTEM
SYSTEM
4WD SYSTEM
4WD SYSTEM : System DescriptionINFOID:0000000006222224
 In AUTO mode, distribution of traction force is cont
rolled from 2WD status (0:100) to 4WD status (50:50)
according to signal from each sensor and switch.
 In accordance with fail-safe function, when system is malfunctioning, 4WD warning lamp on combination meter turns ON and 4WD control stops. For fail-safe function, refer to DLN-20, "
4WD SYSTEM : Fail-Safe".
 When a high load status continues for transfer assembly (transfer control actuator or transfer fluid), 4WD
control temporarily becomes 4H or 2WD status, according to protection function.
NOTE:
4WD system is not malfunctioning.
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL
It transmits/receives each signal from the followi ng transfer control unit via CAN communication line.
JPDIE0272GB
Component parts Control signal
ABS actuator and electric unit (control unit) Transmits the following signals via CAN communication line to transfer control unit.
 Vehicle spee
d signal (ABS)
 Stop lamp switch signal (brake signal)
 ABS operation signal
 VDC operation signal
 TCS operation signal
ECM Transmits the following signals via CAN communication line to transfer control unit.
 Accelerator pedal position signal
 Engine speed signal
 Engine torque signal
Revision: 2010 May2011 QX56

SYSTEMDLN-19
< SYSTEM DESCRIPTION > [TRANSFER: ATX90A]
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4WD SHIFT SWITCH AND 4WD SHIFT INDICATOR LAMP
*1: Blinking 2 times/1 second
*2: “4HI” and “4LO” blink alternately.
CONDITION FOR TURN ON THE WARNING LAMP
TCM Transmits the following signals via CAN communication line to transfer control unit.
 Shift position signal
 Gear position signal
 Output shaft revolution signal
Steering angle sensor Transmits the following signals via CAN communication line to transfer control unit.
 Steering angle sensor signal
Combination meter Receives the following signals via CAN communication line from transfer control unit.
 4WD warning lamp signal
 ATP warning lamp signal
 4WD mode indicator signal
Component parts Control signal
4WD shift switch 4WD shift indicator lamp (in Information display) 4WD shift procedure
AUTO
1. Start the engine.
2. Turn the 4WD shift switch.
NOTE:
Mode can be switched between AU-
TO⇔4H while driving straight.
4H
↓↑
4WD status: 4H ⇔4L (Blinking)
*1*2
1. Start the engine.
2. Never drive the vehicle.
3. Shift A/T shift selector to N position.
4. Press and rotate 4WD shift switch
while depressing brake pedal.
CAUTION:
4WD mode does not switch when 4WD
shift switch is operated while the vehi-
cle is running or A/T shift selector is
shifted to any position other than neu-
tral.
4L
JPDIE0230ZZJPDIE0234ZZ
JPDIE0231ZZJPDIE0235ZZ
JPDIE0231ZZ
JPDIE0233ZZ
JPDIE0236ZZ
JPDIE0233ZZJPDIE0237ZZ
Revision: 2010 May2011 QX56

DLN-20
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
SYSTEM
4WD Warning Lamp
 Turns ON when there is a malfunction in 4WD system. 4W
D warning lamp indicates the vehicle is in fail-safe
mode.
 Also turns ON when ignition switch is turned ON, fo r the purpose of lamp check. Turns OFF approximately
for 1 second after the engine starts if system is normal.
ATP Warning Lamp
When the A/T shift selector is in P position, the vehicle may move if the transfer case in neutral. ATP warning
lamp is turned on to indicate this condition to the driver.
CONDITION FOR OPERATE WARNING BUZZER
For preventing an incorrect operation during 4H ⇔4L switching, warning buzzer sounds from inside of transfer
control unit and warns the driver, when certain conditions are satisfied.
4WD SYSTEM : Fail-SafeINFOID:0000000006303692
 If any malfunction occurs in 4WD electrical system, and control unit detects the malfunction, 4WD warning
lamp on combination meter turns ON to indicate system malfunction.
 When 4WD warning lamp is ON, vehicle changes to rear-wheel drive or shifts to 4-wheel drive (front-wheels
still have some driving torque).
Condition 4WD warning lamp
Lamp check Turns ON when ignition switch is turned ON. Turns OFF ap-
prox. 1 second after the engine start.
4WD system malfunction ON
Protection function is activated due to heavy load to transfer assem-
bly. (4WD system is not malfunctioning.) Quick blinking: 2 times/second
(Blinking in approx. 1 minute and then turning OFF)
Large difference in diameter of front/rear tires Slow blinking: 1 time/2 seconds
(Continuing to blink until turning ignition switch OFF)
Other than above (system normal) OFF
Condition Warning buzzer
4WD shift status A/T shift selector Engine speed
4H⇔4L N range 350
− 1.600 rpm OFF
Under 350 rpm or over 1.600 rpm ON
Except N range Always
Revision: 2010 May2011 QX56

DIAGNOSIS SYSTEM (TRANSFER CONTROL UNIT)
DLN-21
< SYSTEM DESCRIPTION > [TRANSFER: ATX90A]
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DIAGNOSIS SYSTEM (TRA NSFER CONTROL UNIT)
CONSULT-III FunctionINFOID:0000000006222226
FUNCTION
CONSULT-III can display each diagnostic item using the diagnostic test modes as follows.
*: The following diagnosis information is erased by erasing.
DTC
ECU IDENTIFICATION
Transfer control unit part number can be read.
SELF DIAGNOSTIC RESULT
Refer to DLN-29, "DTC Index".
When "0" is displayed on self-diagnosis result.
 The system is presently malfunctioning.
When except "0" is displayed on self-diagnosis result. System malfunction in the past is detec ted, but the system is presently normal.
NOTE:
Each time when ignition switch is turned OFF to ON, numerical number increases in 1 →2→ 3...110 →111 .
When the operation number of times exceeds 111, the number do not increase and “111” is displayed until
self-diagnosis is erased
*.
*: For “U1000” and “U1010”, the maximum value is “39”.
DATA MONITOR
X:Applicable
Diagnostic test mode Function
ECU Identification Transfer control unit part number can be read.
Self Diagnostic Result Self-diagnostic results can be read and erased quickly.*
Data Monitor Input/Output data in the transfer control unit can be read.
Work Support This mode enables a technican to adjust some devices faster and more accurately by following the
indications on the CONSULT-III
Monitor item (Unit) SELECT MONITOR ITEM
Remarks
ECU INPUT
SIGNALS MAIN SIG-
NALS
4WD MODE [BOTNG/SWTNG/4L/4H/AUTO] X Control status of 4WD mode is displayed.
2WD SW [On/Off] X 4WD shift switch (2WD) is not equipped, but it
is displayed.
AUTO SW [On/Off] X 4WD shift switch signal (AUTO) is displayed.
4H SW [On/Off] X 4WD shift switch signal (4H) is displayed.
4L SW [On/Off] X 4WD shift switch signal (4L) is displayed.
T/M RANGE [D/N/R/P] X A/T shift selector position via CAN communica-
tion line is displayed.
N RANGESW [On/Off] X A/T shift selector position (N) via CAN commu-
nication line is displayed.
R RANGE SW [On/Off] X A/T shift selector position (R) via CAN commu-
nication line is displayed.
ING SW [On/Off] X Ignition switch status is displayed.
TCS OPER [On/Off] X TCS operation status via CAN communication
line is displayed.
VDC OPER [On/Off] X VDC operation status via CAN communication
line is displayed.
Revision: 2010 May2011 QX56

DLN-22
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
DIAGNOSIS SYSTEM (T
RANSFER CONTROL UNIT)
ABS OPER [On/Off] X ABS operation status via CAN communication
line is displayed.
SAND MODE IND [On/Off] This indicator is not equipped, but it is dis-
played.
ROCK MODE IND [On/Off] This indicator is not equipped, but it is dis-
played.
SNOW MODE IND [On/Off] This indicator is not equipped, but it is dis-
played.
ONROAD MODE IND [On/Off] This indicator is not equipped, but it is dis-
played.
SAND MODE SW [On/Off] X This switch is not equipped, but it is displayed.
ROCK MODE SW [On/Off] X This switch is not equipped, but it is displayed.
SNOW MODE SW [On/Off] X This switch is not equipped, but it is displayed.
ONROAD MODE SW [On/Off] X This switch is not equipped, but it is displayed.
HI/LO POSI SEN 3 [On/Off] X Transfer Hi-Lo position sensor (3) status is dis-
played.
HI/LO POSI SEN 1 [On/Off] X Transfer Hi-Lo position sensor (1) status is dis-
played.
LOCK POSI SEN [OPEN/LOCK/BAT/UNLEAN/HI
TEMP/ERROR/GND] X
Transfer lock position sensor signal is dis-
played.
ATP IND [On/Off] Control status of ATP warning lamp is dis-
played.
4WD FAILLAMP [On/Off] X Control status of ATP warning lamp is dis-
played.
4WD MODE IND [4L/LOCK/AUTO] X Control status of 4WD mode indicator lamp is
displayed.
(LOCK means 4H of 4WD mode)
MOTOR DRIVE B [HI/LO/PWM] X Driving status of transfer motor is displayed.
(Reverse side)
MOTOR DRIVE A [HI/LO/PWM] X Driving status of transfer motor is displayed.
(Drive side)
FLUID TEMP SEN [V] X Temperature of transfer fluid is displayed.
MOTOR TEMP [V] X Temperature of transfer motor is displayed.
C/U POWER SUP [V] X Power supply voltage value of transfer control
unit is displayed.
MOTOR POWER SUP [V] X Power supply voltage value of transfer motor
unit is displayed.
ROTARY POSI SEN [%] X Transfer rotary position sensor signal is dis-
played.
THRTL POSI SEN [%] X X Throttle opening status via CAN communica-
tion line is displayed.
AT R SPEED [km/h] X Output shaft revolution speed via CAN commu-
nication line is displayed.
T/M GEAR [0 - 7] X Current transmission gear via CAN communi-
cation line is displayed.
COMPR VHCL SPEED [km/h] X Vehicle speed calculated by transfer control
unit is displayed.
VHCL/S SEN-FR [km/h] X Wheel speed (front) average calculated by
transfer control.
Monitor item (Unit)
SELECT MONITOR ITEM
Remarks
ECU INPUT
SIGNALS MAIN SIG-
NALS
Revision: 2010 May2011 QX56

DLN-24
< ECU DIAGNOSIS INFORMATION >[TRANSFER: ATX90A]
TRANSFER CONTROL UNIT
ECU DIAGNOSIS INFORMATION
TRANSFER CONTROL UNIT
Reference ValueINFOID:0000000006222227
VALUES ON THE DIAGNOSIS TOOL
Monitor item Condition Value/Status
4WD MODE IGN ON 4WD is booting BOTNG
4WD mode is switching SWTNG
4WD mode: 4L 4L
4WD mode: 4H 4H
4WD mode: AUTO AUTO
2WD SWITCH
*1Always OFF
AUTO SWITCH 4WD shift switch: AUTO ON
4WD shift switch: 4H or 4L OFF
4H SWITCH 4WD shift switch: 4H ON
4WD shift switch: AUTO or 4L OFF
4L SWITCH 4WD shift switch: 4L ON
4WD shift switch: AUTO or 4H OFF
T/M RANGE A/T shift selector: D D
A/T shift selector: N N
A/T shift selector: R R
A/T shift selector: P P
N RANGE SW A/T shift selector: N ON
A/T shift selector: Except N OFF
R RANGE SW A/T shift selector: R ON
A/T shift selector: Except R OFF
IGN SW IGN SW: ON ON
IGN SW: OFF OFF
TCS OPER SW TCS is operating ON
TCS is not operating OFF
VDC OPER SW VDC is operating ON
VDC is not operating OFF
ABS OPER SW ABS is operating ON
ABS is not operating OFF
SAND MODE IND
*2Always OFF
ROCK MODE IND
*2Always OFF
SNOW MODE IND
*2Always OFF
ONROAD MODE IND
*2Always ON
SAND MODE SW
*3Always OFF
ROCK MODE SW
*3Always OFF
SNOW MODE SW
*3Always OFF
ONROAD MODE SW
*3Always ON
Revision: 2010 May2011 QX56

TRANSFER CONTROL UNITDLN-25
< ECU DIAGNOSIS INFORMATION > [TRANSFER: ATX90A]
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HI-LO POSI SEN 3 4WD mode: AUTO or 4H ON
4WD mode: Shifting OFF
4WD mode: 4L OFF
HI-LO POSI SEN 1 4WD mode: AUTO or 4H ON
4WD mode: Shifting ON
4WD mode: 4L OFF
LOCK POSI SEN When lock sleeve is opening OPEN
When lock sleeve locking LOCK
When transfer lock position sensor
signal circuit is short. (Battery
short) BAT
When transfer lock position sensor is unlearned. UNLEAN
When the temperature of transfer lock position sensor is high. HI TMP
When transfer lock position sensor is malfunctioning. ERROR
When transfer lock position sensor signal circuit is short. (Ground
short) GND
AT P I N D ATP lamp: ON ON
AT P l a m p : O F F O F F
4WD FAIL LAMP 4WD warning lamp: ON ON
4WD warning lamp: OFF OFF
4WD MODE IND 4WD shift switch: AUTO AUTO
4WD shift switch: 4H LOCK
4WD shift switch: 4L 4L
MOTOR DRIVE B When transfer motor is driving in reversal. (100% duty controlled) HI
When transfer motor is driving or stopping. LO
When transfer motor is driving in reversal. (PWM output) PWM
MOTOR DRIVE A When transfer motor is driving. (100% duty controlled) HI
When transfer motor is driving in reversal or stopping. LO
When transfer motor is driving. (PWM output) PWM
FLUID TEMP SE The temperature of transfer fluid is 20 – 80 °C. Approx. 1.1 – 0.3 V
MOTOR TEMP The temperature of transfer motor is 20 – 80 °C. Approx. 1.1 – 0.3 V
C/U POWER SUP Always Battery voltage
MOTOR POWER SUP Always Battery voltage
ROTARY POSI SEN 4WD mode: AUTO
A/T shift selector: DDepress the accelerator pedal several
times.
Value is changing
THRTL POS SEN When depressing accelerator pedal
(Value rises gradually in response to throttle position) 0 – 100 %
AT R SPEED Vehicle stopped 0.00 km/h (0.00 mph)
Vehicle driving (4WD mode: AUTO)
CAUTION:
Check air pressure of tire under standard condition. Approx. equal to the indication
on speedometer (inside of ±10
%)
T/M GEAR A/T shift selector: D
Vehicle driving 1
2
3
4
5
6
7
Monitor item Condition Value/Status
Revision: 2010 May2011 QX56