2013 Lexus GX460 differential

326
2-4. Using other driving systems
GX460_OM_OM60J63U_(U)
Four-wheel drive system
Use the four-wheel drive control switch and center differential lock/unlock
switch to select the following transfer and center differential modes.
■Four-wheel drive control switch
H4 (high speed position)
Normal driving on all types of
roads.
L4 (low speed position)
Driving requiring maximum
power and traction such as
climbing or descending steep
hills, off-road driving, and hard
pulling in sand or mud, etc.
The low speed four-wheel
drive and VSC OFF indica-
tors will come on.
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327
2-4. Using other driving systems
2
When driving
GX460_OM_OM60J63U_(U)
■Center differential lock/unlock switch
Lock the center differential
when your vehicle’s wheels get
stuck in a ditch or when driving
on a slippery or bumpy surface.
The center differential lock indi-
cator will come on.
Unlock the center differential
after the wheels have been
freed, or after moving to a flat,
non-slippery surface.
To unlock the center differential,
push the switch again.
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330
2-4. Using other driving systems
GX460_OM_OM60J63U_(U)
■When the center differential lock/unlock switch can be operated
The “ENGINE START STOP” switch is in IGNITION ON mode.
■The center differential lock indicator light
●The indicator light blinks while locking/unlocking the center differential.
●If the center differential lock indicator light blinks and the buzzer sounds when
the center differential is locked, stop the slipping or spinning and push the
switch again.
If the indicator continue to blink even if doing so, have the vehicle inspected by your
Lexus dealer as soon as possible. There may be a trouble in the four-wheel drive
system.
■Locking/unlocking the center differential
●When the four-wheel drive control switch is in L4 with the center differential
locked, VSC is automatically turned off. (The center differential lock and VSC
OFF indicator light will come on.)
●If the operation is not completed, the center differential lock indicator blinks. If
the indicator light does not turn off when unlocking the center differential, drive
straight ahead while accelerating or decelerating, or drive in reverse.
●Avoid turning suddenly while the center differential is locked. If you do turn sud-
denly, the difference in turning speeds between the front and rear wheels may
have a similar effect to braking, thus making driving difficult.
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331
2-4. Using other driving systems
2
When driving
GX460_OM_OM60J63U_(U)
CAUTION
■While driving
Observe the following precautions. Failure to do so may cause an accident result-
ing in death or serious injury.
●Never move the four-wheel drive control switch if the wheels have lost traction.
●Do not operate the center differential lock/unlock when the vehicle is turning or
when its wheels are spinning freely off the ground.
NOTICE
■To prevent damage to the center differential
●For normal driving on dry and hard surface roads, unlock the center differential.
●Unlock the center differential after the wheels are out of the ditch or off the slip-
pery or bumpy surface.
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362
2-5. Driving information
GX460_OM_OM60J63U_(U)
NOTICE
■To prevent the water damage
Take all necessary safety measures to ensure that water damage to the engine or
other components does not occur.
●Water entering the engine air intake will cause severe engine damage.
●Water entering the automatic transmission will cause deterioration in shift quality,
locking up of your transmission accompanied by vibration, and ultimately dam-
age.
●Water can wash the grease from wheel bearings, causing rusting and premature
failure, and may also enter the differentials, transmission and transfer case, reduc-
ing the gear oil’s lubricating qualities.
■When you drive through water
If driving through water, such as when crossing shallow streams, first check the
depth of the water and the bottom of the riverbed for firmness. Drive slowly and
avoid deep water.
■Inspection after off-road driving
●Sand and mud that has accumulated in brake drums and around brake discs may
affect braking efficiency and may damage brake system components.
●Always perform a maintenance inspection after each day of off-road driving that
has taken you through rough terrain, sand, mud, or water. For scheduled mainte-
nance information, refer to the “Warranty and Services Guide”, “Owner’s Manual
Supplement” or “Scheduled Maintenance”.
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390
2-5. Driving information
GX460_OM_OM60J63U_(U)
■AVS (adaptive variable suspension system)
The suspension can be switched for improvement in driveability. (→P. 3 2 5 )
■Break-in schedule
If your vehicle is new or equipped with any new power train components (such as
an engine, transmission, differential or wheel bearing), Lexus recommends that you
do not tow a trailer until the vehicle has been driven for over 500 miles (800 km).
After the vehicle has been driven for over 500 miles (800 km), you can start tow-
ing. However, for the next 500 miles (800 km), drive the vehicle at a speed of less
than 50 mph (80 km/h) when towing a trailer, and avoid full throttle acceleration.
■Maintenance
●If you tow a trailer, your vehicle will require more frequent maintenance due to
the additional load. (See “Owner’s Guide”, “Warranty and Services Guide”,
“Owner’s Manual Supplement” or “Warranty Booklet”.)
●Retighten the fixing bolts of the towing ball and bracket after approximately
600 miles (1000 km) of trailer towing.
■If trailer sway occurs
One or more factors (crosswinds, passing vehicles, rough roads, etc.) can adversely
affect handling of your vehicle and trailer, causing instability.
●If trailer swaying occurs:
• Firmly grip the steering wheel. Steer straight ahead.
Do not try to control trailer swaying by turning the steering wheel.
• Begin releasing the accelerator pedal immediately but very gradually to reduce speed.
Do not increase speed. Do not apply vehicle brakes.
If you make no extreme correction with the steering or brakes, your vehicle and
trailer should stabilize.
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664
4-3. Do-it-yourself maintenance
GX460_OM_OM60J63U_(U)
74WD20 A4WD system, rear differential lock
8P/ S E AT F L30 AFront power seat (left)
9D/ L N O. 225 ADoor lock motor, glass hatch
opener, BODY ECU
10PSB30 APSB ECU
11TI & TE15 ATilt and telescopic steering
12FOG FR15 AFront fog lights
13OBD7. 5 ADLC 3
14A/C7. 5 AAir conditioning system
15AM17. 5 AStarting system
16DOOR RL25 ARear power window (left)
17ECU-IG NO.110 A
Shift lock ECU, VSC ECU, steering
sensor, yaw rate sensor, sequential
switch, auto wiper ECU, back up
relay, tilt & telescopic steering, PSB
ECU, DSS#1 ECU, front radar sensor,
AFS ECU, TIRE PRESS ECU,
DRIVER MON ECU
18IG17. 5 A
Front turn signal light, rear turn signal
light, side turn signal light, meter turn
signal light, trailer light, ALT, VSC, C/
C switch
FuseAmpereCircuit
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5
When trouble arises
689
5-1. Essential information
GX460_OM_OM60J63U_(U)
■Before emergency towingThe “ENGINE START STOP” switch must be in the ACCESSORY mode
(engine off) or IGNITION ON mode (engine running).
Put the four-wheel drive control switch in H4. (The center differential is
unlocked.)
Put the vehicle height in the N mode and press height control switch to
turn off the rear height control air suspension.
Shift the shift lever in N.
Release the parking brake.
CAUTION
■Caution while towing
●Use extreme caution when towing the vehicle.
Avoid sudden starts or erratic driving maneuvers which place excessive stress on
the emergency towing eyelets and the cables or chains. Always be cautious of the
surroundings and other vehicles while towing.
●Do not turn the “ENGINE START STOP” switch off.
Doing so will lock the steering wheel an d prevent operation, possibly causing an
accident and resulting in death or serious injury.
●If the engine is not running, the power assist for the brakes and steering will not
function, making steering and braking more difficult.
STEP1
STEP2
STEP3
STEP4
STEP5
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