ignition Lexus GX470 2003 Basic Functions / LEXUS 2003 GX470 (OM60A45U) Repair Manual

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301
“LOCK” Engine is off and the steering wheel is locked.
The ignition key can be removed only at this position.
To turn the key from “ACC” to the “LOCK” position, you must
put the transmission selector lever in the “P” position.
Once you remove the key, the engine immobiliser system is
automatically set. See “Engine immobiliser system” on page
12.
When starting the engine, the key may seem stuck at the
“LOCK” position. To free it, first be sure the key is pushed all
the way in, and then rock the steering wheel slightly while
turning the key gently.
If, in an emergency, you must turn the engine off while the
vehicle is moving, turn the key only to “ACC”.
PARKING BRAKE
To set: Pull up the lever. For better holding power, first
depress the brake pedal and hold it while setting the
parking brake.
To release: Pull up the lever slightly (
1 ), press the lock
release button ( 2 ), and lower the lever ( 3 ).
Before leaving your vehicle, firmly apply the parking brake. For
better holding power, first depress the brake pedal and hold it
while setting the parking brake.
CAUTION
Before driving, make sure the parking brake is fully
released and that the parking brake reminder light is off.

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HOW TO START THE ENGINE
Cranking hold function
Once you turn the ignition key to “START” position and release
it, the cranking hold function continues to crank the engine in
“ON” position until it starts.
The function stops cranking the engine after about 25 seconds
maximum if the engine has not started yet. When you crank
the engine again, wait a few seconds and restart it.
If you hold the key in “START” position, the function will keep
cranking for about 30 seconds maximum.
Before cranking
1. Apply the parking brake firmly.
2. Turn off unnecessary lights and accessories.
3. Put the selector lever in “P”. If you need to restart the engine
while the vehicle is moving, put the selector lever in “N”. A
starter safety device will prevent the starter from operating if
the selector lever is in any drive position.
4. Depress the brake pedal and hold it to the floor until driving
off.
Starting the engine
Before starting the engine, be sure to follow the instructions in
“Before cranking”.
Normal starting procedure
The multiport fuel injection system/sequential multiport fuel
injection system in your engine automatically controls the
proper air −fuel mixture for starting. You can start a cold or hot
engine as follows:
1. With your foot off the acce lerator pedal, turn the ignition key
to “START” position, then release it.
2. After the engine runs for about 10 seconds, you are ready
to drive.
If the weather is below freezing, let the engine warm up for a
few minutes before driving. Do not leave the vehicle while the
engine is warming up.
If the engine stalls ...
Simply restart it , using the correct procedure given in normal
starting.
If the engine will not start ...
See “If your vehicle will not start” on page 359.
NOTICE
 Do not race a cold engine.
 If the engine becomes difficult to start or stalls
frequently, have the engine checked immediately.

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AUTOMATIC TRANSMISSION
Your automatic transmission has a shift lock system to
minimize the possibility of incorrect operation. This
means you can only shift out of “P” position when the
brake pedal is depressed with the ignition switch in “ON”
position ()
31PY039
The shift position is displayed beside the selector lever
and on the instrument cluster.
P: Parking, engine starting and key removal position
R: Reverse position
N: Neutral position
D: Normal driving position (Shifting into overdrive possible)
4: Position for engine braking (Shifting into overdrive not
possible)
When the cruise control is being used, even if you
downshift from “D” to “4”, engine braking will not be
enabled because the cruise control is not cancelled. For
the operation to decrease the vehicle speed, see page
314.
3, 2: Position for more powerful engine braking
L: Position for maximum engine braking

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304Correct
use of the automatic transmission is explained in
the following parts.
(a) Normal driving
(b) Using engine braking
(c) Using the “3”, “2” and “L” positions
(d) Backing up
(e) Parking
(f) Good driving practice
(g) If you cannot shift the selector lever
(h) Driving in second start mode
(a) Normal driving
 1 “P” (Park) position 2 “N” (Neutral) position
1. Start the engine as instructed in “How to start the
engine” on page 302.
The transmission must be in “P” or “N”. The engine will not st\
art
in any drive position even if the ignition key is turned to
“START”.

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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 the system on
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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(e) Height control indicator lights
 1 Height control indicator lights

2 Height control “OFF” indicator light
When the ignition switch is turned on, all the indicator lights
come on. Only the indicator light showing the present mode
remains on and all other lights go off after a few seconds. This
means the system operates correctly.
When you change the vehicle height mode, the indicator lights
change as follows:
When changing the vehicle height from the “N” mode to
“HI”:
1. The “N” mode indicator light goes off and the “HI” mode
indicator light blinks.
2. After the vehicle height control reaches the “HI” mode, the
“HI” mode indicator light remains on. If the underbody of the vehicle has touched the surface on
bumpy roads or the area around the rear suspension is
coated with ice, the height control suspension will not
operate and the indicator lights change as follows:
1. The present mode indicator light goes off and the selected
mode indicator light blinks.
2. The selected mode indicator light goes off. (The vehicle
height does not change.) The present mode indicator light
comes on again.
Height control “OFF” indicator light:
When the ignition
switch is turned on, this light comes on. If it goes out after a few
seconds, the rear height control air suspension operates
correctly. If you push the “HEIGHT CONTROL OFF” switch,
the rear height control air suspension is turned off. The height
control “OFF” indicator light comes on.
In the following cases, there is a problem somewhere in the
rear height control air suspension. Although there is no
problem to continue normal driving, have the rear height
control air suspension checked by your Lexus dealer as soon
as possible.
 The height control “OFF” indicator light does not come on
when the ignition switch is turned on.
 The height control “OFF” indicator light blinks.

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When your vehicle is loaded heavily or you are driving in an
unpaved road, the mode

3
or 4
will be recommended. To
provide good vehicle stability, the damping effect will be harder
than for ordinary driving mode.
With the four−wheel drive control lever at “L”, the damping
effect suitable for off −road driving will be harder in any mode.ACTIVE TRACTION CONTROL
SYSTEM
The active traction control system automatically helps
prevent the spinning of 4 wheels when the vehicle is
started or accelerated on slippery road surfaces.
When the ignition key is turned to “ON”, the system
automatically turns on.
CAUTION
Under certain slippery road conditions, full traction of
the vehicle and power to the 4 wheels cannot be
maintained, even though the traction control system is
in operation. Do not drive the vehicle under any speed
or maneuvering conditions which may cause the
vehicle to lose traction control. In situations where the
road surface is covered with ice or snow, your vehicle
should be fitted with snow tires or tire chains. Always
drive at an appropriate and cautious speed for the
present road conditions.

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 Slip indicator light
Leave the system on during the ordinary driving so that it
can operate when needed.
You may hear a sound in the engine compartment for a few
seconds when the engine is started or just after the vehicle
begins to move. This means that the active traction control
system is in the self−check mode, but does not indicate a
malfunction.
When the active traction control system is operating, the
following conditions occur:
 The system controls the spinning of the 4 wheels. At this
time, the slip indicator light blinks.
 You may feel vibration or noise in your vehicle, caused by
operation of the brakes. This indicates the system is
functioning properly. The slip indicator light comes on for a few seconds when the
ignition key is turned to “ON”. If the indicator light does not
come on when the ignition is turned on, contact your Lexus
dealer.
“VSC TRAC” warning light
This light warns that there is a problem somewhere in the
following.

Active traction control system
 Vehicle skid control system
 Downhill assist control system
 Hill− start assist control system
When the system is normal and the ignition key is turned to
“ON”, the warning light will come on and will go off after a few
seconds. It is not a malfunction that the warning light may stay
on for 60 seconds after the ignition key is turned to the “ON”
position.

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Depressing the brake pedal repeatedly may turn on the light.
It is normal if it goes out after a few seconds.
The brake actuator temperature increases during continuous
operation of
the above mentioned systems such as on slippery
roads. If the brake actuator temperature becomes too high
while any of the systems is operating, a buzzer will start to
sound intermittently to indicate that the active traction control
system can no longer operate. In this case, immediately stop
your vehicle at a safe place.
If the system continues to operate, the buzzer sound changes
from intermittent to continuous. (The continuous buzzer
sounds for about 3 seconds.) At the time, the “VSC TRAC”
warning light will come on and the active traction control
system temporarily stops operating in order to protect the
brake actuator. (Although the active traction control system
does not operate, there is no problem to continue your driving.)
The system will be automatically restored after a short time and
the “VSC TRAC” warning light goes out.
If the light comes on while driving, the active traction control
system does not work. However, as normal braking operates
when being applied, there is no problem to continue your
driving.
In the following cases, contact your Lexus dealer:
 The warning light does not come on after the ignition key is
turned to “ON”.
 The warning light remains on after the ignition key is turned
to “ON”.
 The warning light comes on while driving.
VEHICLE SKID CONTROL SYSTEM
The vehicle skid control system helps provide integrated
control of the systems such as antilock brake system,
traction control, engine control, etc. This system
automatically controls t he output of the brakes or engine
to help prevent the vehicle from skidding when cornering
on a slippery road surface or operating steering wheel
abruptly.
The vehicle skid control activates when the vehicle speed is
more than following speed:
Four− wheel drive control lever in “H” 15 km/h (9 mph) . . .
Four−wheel drive control lever in “L” 30 km/h (19 mph) . . .
You may hear a sound in the engine compartment for a few
seconds when the engine is started or just after the vehicle
begins to move. This means that the system is in the
self−check mode, but does not indicate a malfunction.
CAUTION
 Do not rely excessively on the vehicle skid control
system. Even if the vehicle skid control system is
operating, you must always drive carefully and
attentively to avoid serious injury. Reckless driving
will result in an unexpected accident. If the slip
indicator light blinks and an alarm sounds, special
care should be taken while driving.

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Only use tires of specified size. The size,
manufacturer, brand and tread pattern for all 4 tires
should be the same. If you use the tires other than
specified, or different type or size, the vehicle skid
control system may not function correctly. When
replacing the tires or wheels, contact your Lexus
dealer.
 In situations where the road surface is covered with
ice or snow, your vehicle should be fitted with snow
tires or tire chains.
 Slip indicator light
If the vehicle is going to skid during driving, the slip indicator
light blinks and an alarm sounds intermittently. Special care
should be taken while driving. The slip indicator light comes on for a few seconds when the
ignition key is turned to “ON”. If the indicator light does not
come on when the ignition is turned on, contact your Lexus
dealer.
Pushing the center differential lock switch automatically
turns
the vehicle skid control system off. At this time, the
“VSC OFF” indicator comes on with the center differential
lock indicator light.
“VSC OFF” indicator light comes on for a few seconds when
the ignition key is turned to “ON”. It will come on again when
you push the center differential lock switch to turn off the
system.
In the following cases, contact your Lexus dealer:
 The indicator light does not come on when the ignition key
is turned “ON”.