2006 INFINITI QX56 wheel torque

ALL-MODE 4WD SYSTEMTF-17
CE F
G H
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K L
M A
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TF
Revision: November 2009 2006 QX56
Transfer Motor Relay Operation
*: After 2.5 seconds have elapsed.

4WD shift switch, PNP switch, Neutral-4LO switch, vehicle speed sensor and throttle position sensor are
used in conjunction with the transfer motor.
WAIT DETECTION SWITCH

The wait detection switch operates when there is “circulating” torque produced in the propeller shaft
(L → H) or when there is a phase difference between 2-4 sleeve and clutch drum (H →L). After the release
of the “circulating ” torque, the wait detection switch helps provide the 4WD lock gear (clutch drum) shifts.
A difference may occur between the operation of the 4WD shift switch and actual drive mode. At this
point, the wait detection switch senses an actual drive mode.

The wait detection switch operates as follows.
–4WD lock gear (clutch drum) locked: ON
–4WD lock gear (clutch drum) released: OFF

The wait detection switch senses an actual drive mode and the 4WD shift indicator lamp indicates the
vehicle drive mode.
NEUTRAL-4LO SWITCH
The neutral-4LO switch detects that transfer gear is in neutral or 4LO (or shifting from neutral to 4LO) condi-
tion by L-H shift fork position.
AT P S W I T C H
ATP switch detects if transfer gear is in a neutral condition by L-H shift fork position.
NOTE:
Transfer gear may be in a neutral condition in 4H-4LO.
2-4WD SHIFT SOLENOID VALVE
The 2-4WD shift solenoid valve operates to apply oil pressure to the wet-multiplate clutch, depending on the
drive mode. The driving force is transmitted to the front wheels through the clutch so the vehicle is set in the
4WD shift switch A/T selector lever position Vehicle speed
(VSS) Accelerator pedal position Motor relay drive
command
2WD ——— OFF
4H (LOCK) and 4LO “
N ” position 0— ON
“ P ” position 00 - 0.07/8
OFF*
0.07/8 - 1/8 HOLD
1/8 - MAX ON
Other than “ R” position 0 < VSS
≤ 50 km/h (31 MPH)
— ON
50 km/h (31 MPH) < VSS < 55 km/h (34 MPH) HOLD
55 km/h (34 MPH) ≤ VSS OFF
“ R ” position —— ON
“ R ” position —— ON
AUTO “
P ” or “ N” position 0
0 - 0.07/8
OFF*
0.07/8 - 1/8 HOLD
1/8 - MAX ON
0 < VSS ≤ 50 km/h (31 MPH)
— ON
50 km/h (31 MPH) < VSS < 55 km/h (34 MPH) HOLD
55 km/h (34 MPH) ≤ VSS OFF
Other than “ R”, "P" and "N"
position 0 < VSS
≤ 50 km/h (31 MPH)
— ON
50 km/h (31 MPH) < VSS < 55 km/h (34 MPH) HOLD
55 km/h (34 MPH) ≤ VSS OFF

TF-18
ALL-MODE 4WD SYSTEM
Revision: November 20092006 QX56
4WD mode. Setting the vehicle in the 2WD mode requires no pressure buildup. In other words, pressure force
applied to the wet-multiplate clutch becomes zero.
CLUTCH PRESSURE SOLENOID VALVE
The clutch pressure solenoid valve distributes torque (front and rear) in AUTO mode.
LINE PRESSURE SWITCH

With the transfer system design, control of the oil pressure provides the transmission of drive torque to the
front wheels. The main pressure to control the oil pressure is referred to as the line pressure.

The line pressure switch determines whether or not adequate line pressure has built up under different
operating conditions.

The line pressure switch turns ON when line pressure is produced.

The line pressure switch senses line pressure abnormalities and turns the 4WD warning lamp ON.
CLUTCH PRESSURE SWITCH

The clutch pressure switch determines whether or not adequate clutch pressure has built up under differ-
ent operating conditions.

The clutch pressure switch turns ON when clutch pressure is produced.

The clutch pressure switch senses clutch pressure abnormalities and turns the 4WD warning lamp ON.
TRANSFER FLUID TEMPERATURE SENSOR
The transfer temperature sensor detects the transfer fluid temperature and sends a signal to the transfer con-
trol unit.
TRANSFER CONTROL UNIT

Transfer control unit controls transfer control device by input signals of each sensor and each switch.

Self-diagnosis can be done.
TRANSFER CONTROL DEVICE
The transfer control device changes the state of transfer assembly between 2WD, AUTO, 4H⇔4LO with the
2WD, AUTO, 4H and 4LO signals of 4WD shift switch.
NOTE:

To shift between 4H ⇔4LO, stop the vehicle, depress the brake pedal and shift the transmission selector
to the "N" position. Depress and turn the 4WD shift switch. The shift switch will not shift to the desired
mode if the transmission is not in "N" or the vehicle is moving. The 4LO indicator lamp will be lit when the
4LO is engaged.

Actuator motor and actuator position switch are integrated.
4WD SHIFT SWITCH AND INDICATOR LAMP
4WD Shift Switch
The 4WD shift switch allows selection from 2WD, AUTO, 4H or 4LO.
4WD Shift Indicator Lamp

Displays driving conditions selected by 4WD shift switch with 2WD, AUTO and 4H indicators while engine
is running. (When 4WD warning lamp is turned on, all 4WD shift indicator lamps are turned off.)

Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.
4LO Indicator Lamp

Displays 4LO condition while engine is running. 4LO indicator lamp flashes if transfer gear does not shift
completely under 2WD, AUTO, 4H ⇔4LO. (When 4WD warning lamp is turned on, 4LO indicator lamp is
turned off.)

Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.

TF-20
ALL-MODE 4WD SYSTEM
Revision: November 20092006 QX56
COMPONENTS FUNCTION
CAN CommunicationEDS002HC
SYSTEM DESCRIPTION
Refer to LAN-26, "CAN COMMUNICATION" .
Component parts Function
Transfer control unit Controls transfer control device and control valves.
Transfer control device Actuator motor and actuator position switch are integrated so as to switch driving types.
2-4WD shift solenoid valve Controls oil pressure and allows selection between 2WD and 4WD.
Clutch pressure solenoid valve Controls oil pressure and distributes torque (front and rear).
Line pressure switch Detects line pressure.
Clutch pressure switch Detects clutch pressure.
Transfer fluid temperature sen-
sor Detects transfer fluid temperature.
Wait detection switch Detects whether or not 4WD lock gear is locked.
Neutral-4LO switch Detects that transfer is under neutral-4LO condition (or shifting through neutral).
ATP switch Detects that transfer is under neutral condition.
4WD shift switch Allows selection from 2WD, AUTO, 4H or 4LO.
4WD warning lamp

Illuminates if malfunction is detected in electrical system of 4WD system.

There is 1 blink every 2 seconds if rotation difference of front wheels and rear wheels is large.

There is 2 blinks every 1 second if high transfer fluid temperature is detected.
ATP warning lamp Indicates that A/T parking mechanism does not operate when A/T selector lever is in
“P ” position
and transfer is under neutral condition.
4WD shift indicator lamp Displays driving condition selected by 4WD shift switch.
4LO indicator lamp Displays 4LO condition.
ABS actuator and electric unit
(control unit) Transmits vehicle speed signal via CAN communication to transfer control unit.
TCM Transmits the following signals via CAN communication to transfer control unit.

Output shaft revolution signal

A/T position indicator signal (PNP switch signal)
ECM Transmits the following signals via CAN communication to transfer control unit.

Engine speed signal

Accelerator pedal position signal

WHEEL AND TIRE ASSEMBLYWT-7
C
DF
G H
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K L
M A
B
WT
Revision: November 2009 2006 QX56
c. If calculated balance weight value exceeds 50 g (1.76 oz), install
two balance weight sheets in line with each other as shown.
CAUTION:
Do not install one balance weight sheet on top of another.
3. Start wheel balancer again.
4. Install drive-in balance weight on inner side of road wheel in the wheel balancer indication position (angle).
CAUTION:
Do not install more than two balance weights.
5. Start wheel balancer. Make sure that inner and outer residual imbalance values are 5 g (0.18 oz) each or below.

If either residual imbalance value exceeds 5 g (0.18 oz), repeat installation procedures.
Wheel balance (Maximum allowable imbalance):
RotationEES001Q1
NOTE:
Follow the maintenance schedule for tire rotation service intervals. Refer to MA-7, "
PERIODIC MAINTE-
NANCE" .
1. Rotate the tires on each side from front to back as shown. Do not include the spare tire when rotating the tires.
CAUTION:
When installing wheels, tighten them diagonally by dividing
the work two to three times in order to prevent the wheels
from developing any distortion.
2. Adjust the tire pressure to specification. Refer to WT-38, "
Tire" .
3. After the tire rotation, retighten the wheel nuts after the vehicle has been driven for 1,000 km (600 miles), and also after every
wheel and tire have been installed such as after repairing a flat
tire.
Maximum allowable imbalance Dynamic (At rim flange)
5 g (0.18 oz) (one side)
Static 10 g (0.35 oz)
SMA056D
Wheel nut torque : 133 N·m (14 kg-m, 98 ft-lb)
SMA829C