2019 Lexus GS300 ABS

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GS350_300_OM_OM30G96U_(U)4-5. Using the driving support systems
Driving assist systems
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the br
akes are applied suddenly, or if the
brakes are applied while drivin g on a slippery road surface
◆Brake assist
Generates an increased level of br aking force after the brake pedal is
depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to contro l skidding when swerving suddenly or turning on
slippery road surfaces
◆Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road sur-
faces by controlling steering performance.
◆TRAC (Traction Control)
Helps to maintain drive power and pr event the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
Helps to prevent the vehicle from ro lling backward when starting on an
incline.
To help enhance driving safety and perf ormance, the following systems oper-
ate automatically in response to variou s driving situations. Be aware, however,
that these systems are supplementary and should not be relied upon too heav-
ily when operating the vehicle.

GS350_300_OM_OM30G96U_(U)
2974-5. Using the driving support systems
4
Driving
◆VGRS (Variable Gear Ratio Steering) (if equipped)
Adjusts the front wheel turning angle in accordance with the vehicle speed
and steering wheel movement
◆DRS (Dynamic Rear Steering) (if equipped)
Contributes to the turning characteristi cs and responsiveness of the vehicle
by slightly adjusting the rear wheel angle of the vehicle in accordance with
steering wheel movement
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn the
steering wheel
◆AVS (Adaptive Variable Suspension system) (if equipped)
By independently controlling the dampin g force of the shock absorbers for
each of the 4 wheels according to the ro ad and driving conditions, this system
helps riding comfort with superior a high level of stability, and helps good vehi-
cle posture
When SPORT S+ mode is selected by the driving mode select switch, the
damping force is suitable for sporty driving (P. 281)
◆LDH (Lexus Dynamic Hand ling system) (if equipped)
Provides independent control of the VGRS, DRS and EPS. Contributes to
turning characteristics at low speeds, responsiveness at medium speeds and
safety at high speeds by controlling th e steering angle of the front and rear
wheels in accordance with the steeri ng wheel operation and vehicle speed
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRAC, VSC, hill-start
assist control, EPS, VGRS (if equipped) and DRS (if equipped) systems
Helps to maintain vehicle stability when swerving on slippery road surfaces by
controlling the brakes, engine output, steering assist, steering ratio and rear
wheel angle

GS350_300_OM_OM30G96U_(U)
3014-5. Using the driving support systems
4
Driving
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC, Hill-start assist
control and VGRS systems
●A sound may be heard from the engine compartment when the brake pedal is
depressed repeatedly, 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 sys-
tems.
●Any of the following conditions may occur when the above systems are operating.
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 afte r the vehicle comes to a stop.
• The brake pedal may pulsate slig htly after the ABS is activated.
• The brake pedal may move down s lightly after the ABS is activated.
■EPS, VGRS and DRS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction.
■Automatic reactivation of TRAC and VSC systems
After turning the TRAC and VSC systems off, the systems will be automatically re-
enabled in the following situations:
●When the engine swit ch is turned off
●If only the TRAC system is turned off, the TRAC will turn on when vehicle speed
increases
If both TRAC and VSC systems are turned off, automatic re-enabling will not occur
when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheating
when there is frequent steering input over an extended period of time. The steering
wheel may feel heavy as a result . Should this occur, refrain from excessive steering input
or stop the vehicle and turn the engine off. The EPS system should return to normal
within 10 minutes.
■Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate;
●The shift lever is in a position other than N or P (when starting off forward/backward on
an upward incline).
●The vehicle is stopped.
●The accelerator pedal is not depressed.
●The parking brake is not engaged.
■Automatic system cancelation of hill-start assist control
The hill-start assist control will be cancel ed in any of the following situations;
●The shift lever is shifted to N or P.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse after the brake pedal is released.

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GS350_300_OM_OM30G96U_(U)4-5. Using the driving support systems
WARNING
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded. (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 is operating may exceed that of normal conditions
The ABS is not designed to shorten the vehi cle’s stopping distance. Always maintain a
safe distance from the vehicle in front of you, especially in the following situations:
●When driving on dirt, grav el or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or uneven surfaces
■TRAC may not operate effectively when
Directional control and power may not be achievable wh ile driving on slippery road
surfaces, even if the TRAC system is operating.
Drive the vehicle carefully 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 control. The hill-start assist control may not
operate effectively on steep inclines and roads covered with ice.
●Unlike the parking brake, hill-start assist co ntrol is not intended to hold the vehicle
stationary for an exte nded period of time. Do not atte mpt to use hill-start assist con-
trol to hold the vehicle on an incline, as doing so may lead to an accident.
■When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may cause an
accident. Exercise particular care when the indicator light flashes.

GS350_300_OM_OM30G96U_(U)
3034-5. Using the driving support systems
4
Driving
WARNING
■When the 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 help ensure vehicle stability and driving force, do not turn the
TRAC/VSC systems off unless necessary.
■Expert mode precautions (GS F)
●Do not use on public roads.
●Use only when the road co nditions and safety of the surrounding area can be
ensured.
●Proper use of expert mode requires a professional level of driving skill. When using
expert mode, always check the road condit ions and surrounding area and drive more
carefully than usual.
■Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and total load
capacity. In addition, make sure that the tire s are inflated to the recommended tire infla-
tion pressure level.
The ABS, TRAC and VSC systems will not function correctly if different tires are
installed on the vehicle.
Contact your Lexus dealer for further in formation when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modi fying the suspension will affect the driving
assist systems, and may cause a system to malfunction.

GS350_300_OM_OM30G96U_(U)
3916-3. Do-it-yourself maintenance
6
Maintenance and care
■Checking fluid level
The brake fluid level should be between the “MAX” and “MIN” lines on the
tank.
■Adding fluid
Make sure to check the fluid type and prepare the necessary item.
■Brake fluid can absorb moisture from the air
Excess moisture in the brake fluid can cause a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
Brake fluid
GS350/GS300GS F
Fluid type FMVSS No.116 DOT 3 or SAE J1703 brake fluid
Items Clean funnel
WARNING
■When filling the reservoir
Take care as brake fluid can harm your ha nds and eyes and damage painted surfaces. If
fluid gets on your hands or in your eyes, fl ush the affected area with clean water imme-
diately. If you still experience discomfort, see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads wear out or
when the fluid level in the accumulator is high.
If the reservoir needs frequent ref illing, there may be a serious problem.

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GS350_300_OM_OM30G96U_(U)6-3. Do-it-yourself maintenance
Air conditioning filter
Turn the engine switch off.
Open the glove box. Lift up the side
with the stay, disconnect the stay
tabs and remove the partition by
pulling horizontally.
Press the tabs and remove the filter
cover.
Press the tabs and remove the filter
case.
The air conditioning filter must be ch
anged regularly to maintain air condi-
tioning efficiency.
Removal method
1
2
3
4

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GS350_300_OM_OM30G96U_(U)
7
When trouble arises
7-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer
sounds
Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, but then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspecte d by your Lexus dealer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
Brake system warning light (warning buzzer) •Low brake fluid
• Malfunction in the brake booster system
 Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
(If equipped)
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
 Immediately stop the vehicle in a safe place and contact your
Lexus dealer.
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The electronic engine control system;
• The electronic throttle control system; or
• The electronic automatic transmission control system
 Have the vehicle inspected by your Lexus dealer immediately.
SRS warning light
Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system
 Have the vehicle inspected by your Lexus dealer immediately.
(U.S.A.)
(Canada)
ABS warning light Indicates a malfunction in:
• The ABS; or
• The brake assist system
 Have the vehicle inspected by your Lexus dealer immediately.