2013 Lexus GX460 Owner's Manual

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DAC (Downhill Assist Control system)∗
∗: If equipped
The DAC 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 cont rol switch is in the L4 position.
■System operation
Shift the “DAC” switch to ON.
The downhill assist control indi-
cator 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.
■Turning off the system
Shift the “DAC” switch to OFF while the system is in operation. The
downhill assist control 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 indi-
cator is flashing to start the system again.
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■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 con-
trol system will stop operating, a buzzer will sound and the DAC indicator will start
flashing, and the TRAC OFF will be shown on the multi-information display. Refrain
from using the system until the DAC indicator stays on and the message goes off.
(The vehicle can be driven normally during this time.)
■Sounds and vibrations caused by the DAC
●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 DAC.
●Either of the following conditions may occur when the DAC 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 DAC indicator does not come on when the “ENGINE START STOP”
switch is turned to IGNITION ON mode.
●The “DAC” 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.
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CAUTION
■When using downhill assist control
Do not rely overmuch on the downhill assist control. This function does not extend
the vehicle’s performance limitations. Always thoroughly check the road conditions,
and drive safely.
■The system may not operate on the following surfaces, which may lead to an acci-
dent causing death or serious injury
●Slippery surfaces such as wet or muddy roads
●Icy surface
●Unpaved roads
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Driving assist systems
To help enhance driving safety and performance, the following systems
operate 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.
■ 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 surface, or in off-
road conditions (such as rough roads, sand and mud)
The Multi Terrain ABS operates in synchronization 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
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■TRAC (Traction Control) for H4 mode
Helps to maintain drive power and prevent the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
■Active TRAC (Traction Control) for L4 mode*
Helps to maintain drive power and prevent the 4 wheels from spinning
when starting the vehicle or accelerating on slippery roads, or in off-road
conditions
■Hill-start assist control
Helps to prevent the vehicle from rolling backward when starting on an
incline or slippery slope
■KDSS (Kinetic Dynamic Suspension System)
KDSS helps to enhance ride comfort and handling response by using a
hydraulic control system to control the suspension stabilizer bars in
response to road surface and driving conditions during cornering or off-
road driving
■ PCS (Pre-Collision System) (if equipped)
→ P. 3 4 7
*: The function only works in vehicles with Multi-terrain Select when Multi-
terrain Select is switched on
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When the VSC/TRAC or Active TRAC/hill-start assist control systems
are operating
If the vehicle is in danger of slip-
ping or rolling backward when
starting on an incline, or if any of
the drive wheels spins, the slip indi-
cator light flashes to indicate that
the VSC/TRAC or Active TRAC/
hill-start assist control systems are
operating.
A buzzer (intermittent) sounds to
indicate that VSC is operating.
The stop lights and high mounted
stoplight turn on when the hill-start
assist control system is operating.
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Disabling the TRAC or Active TRAC/VSC systems
If the vehicle gets stuck in fresh snow or mud, the TRAC or Active TRAC/
VSC systems may reduce power from the engine to the wheels. You may
need to turn the system off to enable you to rock the vehicle in order to
free it.
■ Turning off TRAC or Active TRAC system only
To turn the TRAC or Active TRAC
system off, quickly press and
release the button.
The TRAC OFF will be shown on
the multi-information display.
Press the button again to turn the
system back on.
■Turning off both TRAC or Active TRAC and VSC systems
To turn the TRAC or Active TRAC
and VSC systems off, press and
hold the button for 3 seconds and
more while the vehicle is stopped.
The VSC OFF indicator light will
come on and the TRAC OFF will
be shown on the multi- information
display.
Press the button again to turn the
system back on.
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■When the TRAC OFF is displayed on the multi-information display even if the
VSC OFF switch has not been pressed
TRAC/Active TRAC, hill-start assist control, downhill assist control and Crawl
Control cannot be operated. Contact your Lexus dealer.
■Hill-start assist control operation conditions
●The shift lever is in D or S.
●The brake pedal is not depressed.
■Sounds and vibrations caused by the ABS/Multi Terrain ABS, brake assist, VSC,
TRAC/Active TRAC and hill-start assist control systems
●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 any of these systems.
●Any of the following conditions may occur when the above systems are operat-
ing. None of these indicates 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.
• The brake pedal may pulsate slightly after the ABS/Multi Terrain ABS is acti-vated.
• The brake pedal may move down slightly after the ABS/Multi Terrain ABS is
activated.
■Reactivation of the TRAC or Active TRAC/VSC systems after turning off the
engine
Turning off the engine after turning off the TRAC or Active TRAC/VSC systems
will automatically reactivate them.
■Reactivation of the TRAC or Active TRAC system linked to vehicle speed
When only the TRAC or Active TRAC system is turned off, the TRAC or Active
TRAC system will turn on when vehicle speed increases. However, when both
TRAC or Active TRAC and VSC systems are turned off, the systems will not turn on
even when vehicle speed increases.
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