2017 Lexus GX460 4 wheel drive system

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GX 460 _O M_ OM6 0F 6 8U _(U )4-5. Using the driving support systems
Four-wheel drive system
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 indica-
tor will come on.
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
1
2
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Driving
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 indicator 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.
■Shifting from H4 to L4Stop the vehicle completely with brake pedal held down.
Shift the shift lever to N.
Push and shift the four-wheel drive control switch to L4.
Maintain this condition until the low sp eed four-wheel drive indicator turns on.
■Shifting from L4 to H4
Stop the vehicle completely with brake pedal held down.
Shift the shift lever to N.
Push and shift the four-wheel drive control switch to H4.
Maintain this condition until the low sp eed four-wheel drive indicator turns off.
Center differential lock/unlock switch
Shifting between H4 and L4
1
2
3
1
2
3
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GX 460 _O M_ OM6 0F 6 8U _(U )4-5. Using the driving support systems
■When the four-wheel drive control switch can be operated
●The engine switch is in IGNITION ON mode.
●The shift lever is in the N position.
●The vehicle is stopped completely.
■The low speed four-wheel drive indicator
●The indicator blinks while sw
itching between H4 and L4.
●If the low speed four-wheel drive indicator continues to blink when you operate the
four-wheel drive control switch to the H4 or L4 position, stop the vehicle completely,
shift the shift lever securely into N and then operate the switch again.
●If the shift lever is moved before the low speed four-wheel drive indicator turns on/off,
the transfer mode may not be shifted completely. The transfer mode disengages both
the front and rear drive shafts from the powertrain and allows the vehicle to move
regardless of the shift position. (At this time, the indicator blinks and the buzzer sounds.)
Therefore, the vehicle is free to roll even if the shift lever is in P. You or someone else
could be seriously injured. You must comple te the shifting of the transfer mode and
confirm that the indicator has turned off (H4) or turned on (L4).
●If the engine coolant temperature is too low, the four-wheel drive control system may
not be able to shift. When the engine is warmer operate 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.
■When the transfer mode is switched to L4
Vehicles without Multi-terrain Select:
VSC is automatically turned off. (The VSC OFF indicator will come on.)
Vehicles with Multi-terrain Select:
VSC and TRAC/Active TRAC are automatically turned off. (The VSC OFF indicator will
come on and the “TRAC OFF” will be shown on the multi-information display.)
■When the center differential lock/unlock switch can be operated
The engine switch is in IGNITION ON mode.
■The center differential lock indicator
●The indicator blinks wh ile locking/unlocking the center differential.
●If the center differential lock indicator b links 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.
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Driving
■Locking/unlocking the center differential
●If the operation is not completed, the center differential lock indicator blinks. If the indi-
cator 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 suddenly,
the difference in turning speeds between the front and rear wheels may have a similar
effect to braking, thus making driving difficult.
CAUTION
■While driving
Observe the following precautions. Failure to do so may cause an accident resulting 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 slippery
or bumpy surface.
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Driving
●LO (low mode)
Effective when traveling on rocks, or descending a slope of mogul and rub-
ble.
*
●MED (medium mode)
Effective when ascending a slope of mogul.
*
●HI (high mode)
Effective when ascending a slope of mogul and rubble, or traveling on snow,
dirt, mud, sand, gravel, grass etc.
*
The position between low and medium modes and the position between medium
and high modes can also be selected.
*: Depending on the road surface, may not be the most effective.
■The Crawl Control can be operated when
●The shift lever is in any gear other than P or N.
●The four-wheel drive control switch is in L4.
●The driver’s door is closed.
■Automatic system cancelation
In the following situations, the system is canceled automatically:
At that time, the buzzer will sound, the slip in dicator turns off, and the Crawl Control indi-
cator flashes.
A notification will be displayed on the mult i-information display for several seconds.
( → P. 5 2 8 )
●When the shift lever is moved to P or N.
●When the four-wheel drive control switch is in H4.
●When the driver’s door is opened.
When turning off Crawl Control while traveling, stop the vehicle before the Crawl Con-
trol indicator turns off, or drive extremely carefully.
■Function limit
●In the following situations, you will be able to use brake control to drive downhill at a
fixed low speed, but you will be unable to use engine control to drive uphill at a fixed low
speed.
• When the driving mode is set to second start mode.
• When the vehicle speed is higher than 6 mph (10 km/h).
●When the vehicle speed is higher than 15 mph (25 km/h), engine control and brake
control will stop temporarily. At that time, the Crawl Control indicator flashes.
Speed modes
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Driving
Downhill assist control system∗
Shift the “DAC” switch to ON. The
downhill assist control system indicator
light comes on and the system will
operate.
When the system is in operation, the slip
indicator light will flash, and the stop
lights/high mounted stop lights will be lit.
Shift the “DAC” switch to OFF while the system is in operation. The downhill
assist control system indicator will flash as the system gradually ceases operation,
and will turn off when the system is fully off.
Shift the “DAC” switch to ON while the downhill assist control system indicator is
flashing to start the system again.
∗: If equipped
The downhill assist control system helps to prevent excessive speed on steep
downhill slopes.
The system will operate when the vehicle is traveling under 15 mph (25 km/h)
and the four-wheel drive control switch is in the L4 position.
System operation
Turning off the system
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GX 460 _O M_ OM6 0F 6 8U _(U )4-5. Using the driving support systems
■Operating tips
The system will operate when the shift lever is
in a position other than P, however to make
effective use of the system it is recommended that the shift lever be shifted to 2 or 1 range
of S mode.
■If the four-wheel drive control switch is in H4
The system does not operate.
■When the downhill assist control system is operated continuously
This may cause the brake actuator to overheat . In this case, the downhill assist control
system will stop operating, a buzzer will sound and the downhill assist control system
indicator will start flashing, and the “TRAC OF F” will be shown on the multi-information
display. Refrain from using the system until the downhill assist control system indicator
stays on and the message goes off. (The vehicle can be driven normally during this time.)
■Sounds and vibrations caused by the downhill assist control system
●A sound may be heard from the engine compartment when the engine is started or just
after the vehicle begins to move. This sound does not indicate that a malfunction has
occurred in downhill assist control system.
●Either of the following conditions may occu r when the downhill assist control system is
operating. None of these are indicators that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
■System malfunction
●The downhill assist control system indicator does not come on when the engine switch
is turned to IGNITION ON mode.
●The downhill assist control system indicator does not come on when the “DAC” switch
is pressed.
●The slip indicator comes on.
In the above cases, have your vehicle checked by your Lexus dealer.
CAUTION
■When using downhill assist control system
Do not rely overmuch on the downhill assi st control system. This function does not
extend the vehicle’s performance limitations . Always thoroughly check the road condi-
tions, and drive safely.
■The system may not operate on the following surfaces, which may lead to an accident
causing death or serious injury
●Slippery surfaces such as wet or muddy roads
●Icy surface
●Unpaved roads
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Driving
Driving assist systems
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if the brakes are
applied while driving on a slippery road surface
◆Multi Terrain ABS (Anti-lock Brake System) (vehicles with a Multi-terrain
Select system)
Helps to prevent wheel lock when the brakes are applied suddenly, or if the brakes are
applied while driving on a slippery road su
rface, or in off-road conditions (such as
rough roads, sand and mud)
The Multi Terrain ABS operates in synchr onization with the Multi-terrain Select
◆Brake assist
Generates an increased level of braking force after the brake pedal is depressed
when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on slippery
road surfaces
◆TRAC (Traction Control) for H4 position
Helps to maintain drive power and prevent the drive wheels from spinning when start-
ing the vehicle or accelerating on slippery roads
To help enhance driving safety and performance, the following systems oper-
ate automatically in response to various driving situations. Be aware, however,
that these systems are supplementary and should not be relied upon too
heavily when operating the vehicle.
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