2003 Lexus GX470 engine

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See “(b) Shifting procedure” for further instructions.
Advice for driving on slippery roads in “L” (low speed
position) mode
If you shift the four−wheel drive control lever to “L”, the
automatic transmission lever to “2” when you drive in steep
off−road areas, the output of the brake can be controlled
effectively by the active traction control system, which assists
the driver to control the driving power of 4 wheels.
Use the “L” position of the automatic transmission lever for
maximum power and traction when your wheels get stuck or
when you drive down a steep incline. In the following cases,
the out put of the brake can be controlled by the active traction
control system if the engine speed is under 3,000 rpm
(normally engine speed is under 3,000 rpm when the wheels
get unstuck).
 The four− wheel drive control lever in the “L” position and the
automatic transmission lever in the “L” position or the
automatic transmission lever in the “D” or “2” with the
transmission downshifting to the first gear.
 The four− wheel drive control lever in the “L” position and the
automatic transmission lever in the “R” position
(As for the automatic transmission lever positions, see
“Automatic transmission” on page 303.)
(b) Shifting procedure
To shift between unlock and lock modes in “H”, push the
center differential lock button.
To shift between unlock and lock modes in “L”, push the
center differential lock button.
To shift between “H” and “L”, stop the vehicle, put the
transmission into “N” and move the four −wheel drive control
lever.
CAUTION
Never move the fourwheel drive control lever if wheels
are slipping. Stop the slipping or spinning before
shifting.
NOTICE
For normal driving on dry and hard surface roads,
unlock the center differential. To prevent damage to the
center differential lock system, do not push the center
differential lock button when the vehicle is cornering or
when its wheels are spinning freely of f the ground. If the
indicator light does not go off when unlocking the
center differential, drive straight ahead while
accelerating or decelerating, or drive in reverse.

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CRUISE CONTROL
The cruise control allows you to cruise the vehicle at a
desired speed over about 40 km/h (25 mph) with your foot
off the accelerator pedal.
Your cruising speed can be maintained although a slight speed
change may occur when driving up or down a gradient, within
the limits of engine performance. On steeper hills, a greater
speed change will occur so it is better to drive without the cruise
control.
When the cruise control is on, the driving pattern of the
automatic transmission is fixed in the normal position,
regardless of the position of the driving pattern selector switch.
CAUTION
 To help maintain maximum control of your vehicle,
do not use the cruise control when driving in heavy
or varying traffic, or on slippery (rainy, icy or
snowcovered) or winding roads.
 Avoid vehicle speed increases when driving
downhill. If the vehicle speed is too fast in relation to
the cruise control set speed, cancel the cruise
control then downshift the transmission to use
engine braking to slow down.
Turning on the system
To operate the cruise control, push the main switch. This turns
the system on. The indicator light in the instrument cluster
shows that you can now set your desired cruising speed.
Another push on the switch will turn the system completely off.
When the ignition key is turned off, the main switch is also
automatically turned off. To use the cruise control again, push
the main switch again to turn it on.
CAUTION
To avoid accidental cruise control engagement, keep
the main switch off when not using the cruise control.

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4Resetting to a slower speed
Press the control lever downward in the “ − / SET” direction and
hold it. Release the lever when the desired speed is attained.
While the lever is held downward, the vehicle speed will
gradually decrease.
When the difference between the actual vehicle speed and the
set speed is less than 5 km/h (3 mph), the set speed can be
lowered 1.6 km/h (1 mph) each time by pressing the control
lever downward in the “ − / SET” direction quickly within 0.6
seconds.
However, a quicker way to reset is to depress the brake pedal
and then press the control lever downward in the “ − / SET”
direction.
Even if you downshift the transmission from the “D” position to
“4” position with the cruise control on, engine braking will not
be applied because the cruise control is not cancelled. To
decrease the vehicle speed, reset to a slower speed with the
cruise control lever or depress the brake pedal. If you use the
brake pedal, cruise control is cancelled.
5Resuming the preset speed
If the preset speed is cancelled by pulling the control lever or
by depressing the brake pedal, pushing the lever up in the “+
/ RES” direction will restore the speed set prior to cancellation.
However, once the vehicle speed falls below about 40 km/h (25
mph), the preset speed will not be resumed.
Cruise control failure warning
If the “CRUISE” indicator light in the instrument cluster flashes
when using the cruise control, push the main switch to turn the
system off and then push it again to turn it on.
If any of the following conditions then occurs, there is some
trouble in the cruise control system.
 The indicator light does not come on.
 The indicator light flashes again.
 The indicator light goes out after it comes on.
If this is the case, contact your Lexus dealer and have your
Lexus inspected.

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REAR HEIGHT CONTROL AIRSUSPENSION
This rear height control air suspension controls the
vehicle height depending on the vehicle driving condition.
Select your desired height among the “HI” (high), “N”
(normal) and “LO” (low) modes with the height select
switch.
(a) Vehicle height modes
“N” (normal) mode: The vehicle height in this mode is
standard. Regardless of the number of occupants or the
luggage loading condition, the vehicle height is always
automatically adjusted to a fixed height in any mode while the
engine is running.
This mode is suitable for ordinary driving. “HI”
(high) mode: The vehicle height is about 40 mm (1.6 in.)
higher at the rear than the “N” mode height.
This mode is suitable when driving on the bumpy roads and
through water.
However, when the vehicle speed exceeds about 30 km/h (19
mph) or over in the “HI” mode, the “N” mode is automaticall\
y
selected.
CAUTION
The “HI” mode should be used for severe offroad
driving condition only. As the vehicle’s center of gravity
is higher in this setting, the vehicle may become
unstable when turning abruptly resulting in accident.
“LO” (low) mode: The vehicle height is about 20 mm (0.8 in.)
lower at the rear than the “N” mode height.
This mode allows you easy access to the vehicle (getting in and
out) and easy loading and unloading operation.
This mode is available when the vehicle speed is under about
12 km/h (7 mph).

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NOTICE
Use the “LO” mode when the vehicle is stopped.
Otherwise, when the vehicle speed exceeds about 12
km/h (7 mph), “N” mode is selected automatically. So
be careful when you drive in any place where the
overhead height is limited.
(b) Vehicle height mode changing condition
To change the vehicle height, it is necessary to meet the
following conditions.
The engine should be running.
 The height control “OFF” indicator light should go off.
 When selecting a mode, there is a vehicle speed limit. Refer
to the following table.
\f = The mode can be selected.
 = The mode cannot be selected.
“LO”
mode“N”
mode“HI”
mode
Under about
12 km/h (7 mph)\f\f\f
Under about
30 km/h (19 mph)\f\f
About 30 km/h
(19 mph) or over\f
In the following cases, the rear height control suspension
will not operate.
 The underbody of the vehicle has touched the surface on
bumpy roads.
 The area around the rear suspension is coated with ice.
If the vehicle is moved to its usual location or the ice is removed
and the height select switch is pressed, the vehicle height
control cannot be operated. In this case, turn off and restart the
engine, then push the control switches.
(c) Vehicle height adjustment
 1 Higher2 Lower
To change the mode, push the height select switch on
either side of “ ” (higher) or “
” (lower).

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The height control indicator light indicates which mode is
selected. (See “(e) Height control indicator light” described
below.)

Selecting the “HI” mode
Push the height select switch on the “ ” side when the vehicle
speed is under about 30 km/h (19 mph).
To change the “N” mode to “HI”: Push the switch once.
To change the “LO” mode to “HI”: Push the switch twice.
It takes about 30 seconds until the “LO” mode changes to the
“HI” mode.
 Selecting the “N” mode
To change the “HI” mode to “N”: Push the height select
switch on the “
” side once.
To change the “LO” mode to “N”: Push the height select
switch on the “ ” side once.
 Selecting the “LO” mode
Push the height select switch on the “
” side while the vehicle
is stopped.
To change the “N” mode to “LO”: Push the switch once.
To change the “HI” mode to “LO”: Push the switch twice.
Even if the engine is stopped while the vehicle height is being
lowered, the operation continues for up to 25 seconds. If within
this 25 seconds, any of the side doors or the back door is
opened, operation will continue for a further 15 seconds.
NOTICE
 If the vehicle height is changed frequently when the
vehicle is heavily loaded, the compressor may
overheat causing the vehicle height adjustment
operation to stop.
 Before you lower the vehicle height with the height
select switch, check under the vehicle to make sure
nothing to damage the vehicle or no one to be injured
is there and that the underbody of the vehicle does
not touch the ground.
 After unloading, the height of a vehicle equipped with
the rear height control air suspension becomes
slightly higher than the normal vehicle height. Take
sufficient care where the overhead height is
restricted.
 Do not select the “LO” mode in the bumpy roads. If
the underbody of the vehicle touches the rugged
road surface, the vehicle may be damaged.

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(d) Turning off the rear height control airsuspension
To turn off the rear height control air suspension with the
vehicle stopped, push the “HEIGHT CONTROL OFF”
switch. The height control “OFF” indicator light comes on
and the vehicle height is fixed in the same mode as the
height control switch is pushed.
This status is memorized in the system even after the engine
is stopped.
If you push the switch again, the height control “OFF” indicator
light goes out and the rear height control air suspension is
turned on.
Even after the rear height control air suspension is turned off
with the “HEIGHT CONTROL OFF” switch, if the vehicle speed
exceeds 30 km/h (19 mph), the rear height control air
suspension automatically selects the “N” mode.
CAUTION
If you drive through deep water over about 700 mm (28
in.) in depth, put the vehicle height in the “HI” mode with
the height select switch and then turn off the rear height
control air suspension by pushing the “HEIGHT
CONTROL OFF” switch.
NOTICE
 When jacking up or installing tire chains, be sure to
turn off the rear height control air suspension with
the “HEIGHT CONTROL OFF” switch and stop the
engine. Otherwise, the vehicle height may change
because of the automatic leveling function resulting
in accident.
 If your vehicle must be towed, put the vehicle height
in the “N” mode and turn off the rear height control air
suspension. Otherwise, the vehicle height may
change because of the automatic leveling function
resulting in accident.
 If your vehicle gets ditched, turn off the rear height
control air suspension with the “HEIGHT CONTROL
OFF” switch. Otherwise, the vehicle height may
change because of the automatic leveling function
resulting in accident.

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(f) Parking and stopping tips
If you immediately stop the engine to park the vehicle after
off−road driving, the vehicle height is lowered slightly as the
vehicle becomes cool. When parking, make sure there is
nothing that will be in contact with the underbody of the vehicle.
When you start the engine, the vehicle returns to the previous
height.
If you park the vehicle for a long time, the vehicle height may
be gradually lowered. When parking for a long time, make sure
there is nothing that will be in contact with the underbody of the
vehicle. When you start the engine, the vehicle returns to the
previous height.
If you stop the engine, the vehicle height may change in
accordance with the change in the temperature. When you
start the engine, the vehicle returns to the previous height.
(g) Rear height control failure warning
If there is a problem somewhere in the rear height control air
suspension, the “N” mode is automatically selected. If this
occurs, the height control “OFF” indicator light blinks and the
vehicle height control cannot be activated until the malfunction
is corrected. If this is the case, bring your vehicle to your Lexus
dealer as soon as possible and have it checked.
ELECTRONIC MODULATED SUSPENSION
This electronic modulated suspension adjusts the
damping effect on the shock absorbers with the control
switch. Select one of the 4 modes which is suited to the
driving conditions with the control switch to provide good
riding comfort and stability.
1 For driving on a bumpy road
2 For ordinary driving such as in the city traffic
3 For moderate high speed driving
4 For sporty type driving such as on winding mountain
roads and high speed driving
5 Soft
6 Firm
We recommend you to select the mode
2
for ordinary
driving. The damping effect will be changed automatically to
provide good riding comfort.