2010 Lexus GX460 Trac

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2-4. Using other driving systems
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When driving
GX460_U.S.A. (OM60E69U)
■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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2-4. Using other driving systems
GX460_U.S.A. (OM60E69U)
■TRAC (Traction Control) for H4 mode
Helps to maintain drive power and prevents the drive wheels from spin-
ning when starting the vehicle or accelerating on slippery roads
■Active TRAC (Traction Control) for L4 mode*
Helps to maintain drive power and prevents 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 3 8
*: The function only works in vehicles with Multi-terrain Select when Multi-
terrain Select is switched on

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2-4. Using other driving systems
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When driving
GX460_U.S.A. (OM60E69U)
When the VSC/TRAC or Active TRAC/hill-start assist control systems
are operatingIf 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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2-4. Using other driving systems
GX460_U.S.A. (OM60E69U)
Disabling the TRAC or Active TRAC/VSC systemsIf 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 more than 3
seconds 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 driving
GX460_U.S.A. (OM60E69U)
■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 vehicl e 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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GX460_U.S.A. (OM60E69U)
■When the brake system operates continuously
The brake actuator may overheat. In this case, the TRAC or Active TRAC and hill-
start assist control systems will stop operating, a buzzer will sound and the TRAC
OFF will be shown on the multi-information display. Refrain from using the system
until the message goes off. (There is no problem with continuing normal driving.)
■If the slip indicator comes on...
It may indicate a malfunction in the VSC, TRAC/Active TRAC or hill-start assist
control system. Consult your Lexus dealer.
CAUTION
■The ABS/Multi Terrain ABS does not operate effectively when
●Tires with inadequate gripping ability are used (such as excessively worn tires on
a snow covered road).
●The vehicle hydroplanes while driving at high speed on wet or slick roads.
■Stopping distance when the ABS/Multi Te rrain ABS is operating will exceed that
of normal conditions
The ABS/Multi Terrain ABS is not designed to shorten the vehicle’s stopping dis-
tance. Always maintain a safe distance from the vehicle in front of you in the follow-
ing situations:
●When driving on dirt, gravel or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or roads with uneven surfaces

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When driving
GX460_U.S.A. (OM60E69U)
CAUTION
■TRAC/Active TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the TRAC/Active TRAC is operating. 
Do not drive the vehicle in conditions where stability and power may be lost.
■Hill- start assist control does not operate effectively when
Do not overly rely on the hill-start assist co ntrol. The hill-start assist control may not
operate effectively on steep incl ines and roads covered with ice.
■When the VSC is activated
The slip indicator light flashes and a warning buzzer sounds. Always drive carefully. 
Reckless driving may cause an accident. Ex ercise particular care when the indica-
tor light flashes and a buzzer sounds.
■When the TRAC or Active TRAC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are the systems to ensure vehicle stability and driving force, do not turn the
TRAC or Active TRAC/VSC systems off unless necessary.
■Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
inflation pressure level.
The ABS/Multi Terrain ABS and VSC systems will not function correctly if different
tires are installed on the vehicle. 
Contact your Lexus dealer for further info rmation when replacing tires or wheels.

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When driving
GX460_U.S.A. (OM60E69U)
PCS (Pre-Collision System)
: If equipped
When the system detects the possibilit y of a frontal collision, the systems
such as the brakes and seat belts are automatically engaged to lessen
impact and injuries to occupant s as well as vehicle damage.
■Pre-collision seat belts (front seat belts only)
If the system detects that a collisio n is unavoidable, the system will
retract the seat belt be fore the collision occurs. 
The same will happen if the driver makes an emergency braking or
loses control of the vehicle. ( P. 8 8 )
However, when the VSC system is disabled, the system will not
operate in the event of skidding.
■ Pre-collision brake assist
When there is a high possibility of a frontal collision, the system
applies greater braking force in rela tion to how strongly the brake
pedal is depressed.
■ Pre-collision braking
When there is a high possibility of a frontal collision, the system
warns the driver using a warning light , warning display and buzzer. If
the system determines that a collision is unavoidable, the brakes are
automatically applied to reduce the collision speed. Pre-collision
braking can be disabled using th e pre-collision braking off switch.