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340
THREE−WAY CATALYTIC
CONVERTERS
G31042
GS430
G31043
GS300Three−way catalytic converters are emission control
devices installed in the exhaust system.
The purpose is to reduce pollutants in the exhaust gas.
CAUTION
Keep people and combustible materials away from
the exhaust pipe while the engine is running. The
exhaust gas is very hot.
Do not drive, idle or park your vehicle over anything
that might burn easily such as grass, leaves, paper or
rags.
NOTICE
A large amount of unburned gases flowing into the
three−way catalytic converter may cause it to overheat
and create a fire hazard. To prevent this and other
damage, observe the following precautions:
Use only unleaded gasoline.
Do not drive with an extremely low fuel level; running
out of fuel could cause the engine to misfire, creating
an excessive load on the three−way catalytic
converter.
Do not allow the engine to run at idle speed for more
than 20 minutes.
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363
(e) Parking
G31029
1
Parking brake pedal 2
Brake pedal
3
“P” (Park) position
1. Bring the vehicle to a complete stop.
2. Depress the parking brake pedal fully to securely apply the
parking brake.
3. With the brake pedal held down with your foot, shift the
selector lever to the “P” position.
CAUTION
Never attempt to move the selector lever into “P” under
any circumstances while the vehicle is moving. Serious
mechanical damage and loss of vehicle control may
result.
(f) Good driving practice
If the transmission repeatedly shifts up and down between
fourth and overdrive gears when climbing a gentle slope, shift
the selector lever to the “4” position. Be sure to shift the
selector lever to the “D” position after climbing the slope.
CAUTION
Always keep your foot on the brake pedal while stopped
with the engine running. This prevents the vehicle from
creeping.
NOTICE
Always use the brake pedal or the parking brake to hold
the vehicle on an upgrade. Do not attempt to hold the
vehicle using the accelerator pedal, as this can cause
the transmission to overheat.
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424
Hill−start assist control system failure
warning
G31039
1
GS430 2
GS300
If the hill−start assist control system malfunctions, the
slip indicator light (two−wheel drive models only) and
brake system warning light (yellow) come on. At this time,
the above message appears. (GS430 only—In some
cases, the multi−information display shows either
“CHECK VSC” or “CHECK ECB” only.)
If the message appears, the hill−start assist control system,
vehicle stability control system and traction control system do
not work. Although it is no problem to continue driving, have
your vehicle checked by your Lexus dealer as soon as
possible.
VARIABLE GEAR RATIO
STEERING SYSTEM
(GS430 only)
The variable gear ratio steering system adjusts the wheel
turning angle depending on the vehicle speed and how
much you turn the steering wheel.
The vehicle wheel turning angle will be changed with a smaller
degree of wheel maneuvering when you are driving at very low
speed such as when putting your vehicle into a garage.
When you start or stop the engine, you may hear a small noise
and the steering wheel may move slightly. This is caused when
the system starts or stops, and does not indicate a malfunction.
In the following cases, to prevent the system from overheating,
the system could be temporarily deactivated with the change
in the center position of the steering wheel. This is not a
malfunction. After the cause of the problem is eliminated, the
system will return to normal automatically after a few minutes.
If you continue maneuvering the steering wheel when the
vehicle is stopped or running at very low speed
If you continue driving holding the steering wheel to the
extreme right or left
If you maneuver the steering wheel immediately after
starting the engine at less than about −30C (−22F)
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ELECTRIC POWER STEERING
SYSTEM
The electric power steering system, using an electric
motor, assists the turning of the steering wheel.
In the following cases, you may feel the steering becomes
heavy. However, the electric power steering system
warning light does not come on. (Because it is not a
malfunction.)
When maneuvering or turning frequently over a long time, the
power steering effect will be reduced to prevent the system
from overheating. Avoid turning the steering wheel, or stop the
vehicle and select the engine switch in “ACC” or “OFF” mode.
The system will become cool in about 10 minutes.
NOTICE
Frequent maneuvering and turning over a long time may
cause damage to the system in which the mechanism
prevents overheating of the electric power steering
system.
When the battery is discharged, check the battery’s condition.
If necessary, recharge or replace the battery. For details, see
“Checking battery condition” on page 571.
G31040
Electric power steering system warning light
The light comes on when the engine switch is selected in
“IG−ON” mode. If the electric power steering system works
properly, the light turns off after a few seconds. If the system
has malfunctions, the light comes on again.
If the following conditions occur, this indicates a
malfunction somewhere in the components monitored by
the warning light system. Contact your Lexus dealer as
soon as possible to service the vehicle.
The light does not come on when the engine switch is
selected in “IG−ON” mode or remains on.
The light stays on while you are driving.