ABS Lexus GS450h 2008 Do-it-yourself maintenance / LEXUS 2008 GS450H OWNER'S MANUAL (OM30A96U)

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2-2. Instrument cluster
GS_HV_U
December 12, 2007 3:50 pm
CAUTION
■If a safety system warning light does not come on
Should a safety system light such as ABS and the SRS airbag warning light not
come on when you turn to ON mode, this could mean that these systems are not
available to help protect you in an accident, which could result in death or serious
injury. Have the vehicle inspected by your Lexus dealer immediately if this occurs.
■ Warning lights
Warning lights inform the driver of malfunctions in the indicated
vehicle’s systems. ( P. 4 9 1 )
*: These lights turn on when the “POWER” switch is turned to ON mode
to indicate that a system check is being performed. They will turn off
after the hybrid system is on, or af ter a few seconds. There may be a mal-
function in a system if the lights do not come on, or turn off. Have the
vehicle inspected by your Lexus dealer.
(U.S.A.)(Canada)(U.S.A.)(Canada)
(U.S.A.)(Canada)(if equipped)
*******
*****
*

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2-4. Using other driving systems
GS_HV_U
January 4, 2008 10:02 am
●In the following situations, the intuitive parking assist may not function correctly,
possibly leading to an accident.
• There is ice, snow or mud on the sensors. (Wiping the sensors will resolve this
problem.)
• The sensor area is frozen. (Thawing the area will resolve this problem.) 
In especially cold weather, if a sensor is frozen the screen may show an abnor-
mal display, or obstacles may not be detected.
• The vehicle angle is especially wide.
• In harsh sunlight or intense cold weather.
• When driving on bumpy, sloped or gravel roads, or over grass.
• If there is something producing ultrasonic waves nearby, such as another vehicle’s horn, motorcycle engine nois e, air braking sound from heavy-duty
vehicles, or another vehicle using the intuitive parking assist.
• In heavy rain, or if water is splashed on the sensors.
• If a commercial fender pole or radio antenna is installed.
• If towing eyelet is installed on your vehicle.
• If moving towards a high curb or a curb corner.
• Objects such as signs may cause the detection distance to shorten.
• The area directly under the bumpers is not detected. 
Objects lower than the sensor s or thin stakes etc. may be detected initially,
but as they draw closer, they may cease to be detected.
• If obstacles draw too close to the sensor.
■Obstacles that may not be detected correctly
The following obstacles may not be detected.
●Thin objects such as wire, fencing or rope.
●Objects that absorb sound wave s, such as cotton or snow.
●Objects with sharp corners.
●Objects where the upper section projects out over the lower section.
●Low objects.
■If the display flashes and a message is displayed
P. 5 1 2

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2-4. Using other driving systems
GS_HV_U
January 4, 2008 10:02 am
Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be aware,
however, that these systems are supplementary and should not be relied
upon too heavily when operating the vehicle.
■ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface.
■ Brake assist
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation.
■VSC (Vehicle Stability Control)
Helps the driver to control skidding wh en swerving suddenly or turning on
slippery road surfaces.
■ TRAC (Traction Control)
Maintains drive power and prevents the rear wheels from spinning when
starting the vehicle or accelerating on slippery roads.
■Hill-start assist control
Helps prevent the vehicle from rolling backwards when starting on an
incline or slippery slope. It operates for approximately 5 seconds at maxi-
mum.
■ EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.
■Active stabilizer suspension system (if equipped)
Turns at smaller angles to main tain the stable vehicle posture.

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2-4. Using other driving systems
2
When driving
GS_HV_U
January 4, 2008 10:02 am
When the VSC/TRAC/hill-start assist control systems are operating
If the vehicle is in danger of slip-
ping, rolling backwards when
starting on an incli ne, or if the rear
wheels spin, the slip indicator light
flashes to indicate that the VSC/
TRAC/hill-start assist control sys-
tems have been engaged.
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.
The slip indicator light flashes as
well when ABS is operating.
■ PCS (Pre-Collision System) (if equipped)
 P. 2 0 6
■VGRS (Variable Gear Ratio Steering)
Adjusts the wheel turning angle in accordance with the vehicle speed and
steering wheel movement.
■VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the AB S, VSC, TRAC, hill-start assist con-
trol, VGRS and EPS systems. 
Maintains vehicle stability when swerving on slippery road surfaces by
controlling the brakes, hybrid output, and the movement of the front
wheels.

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2-4. Using other driving systems
2
When driving
GS_HV_U
January 4, 2008 10:02 am
■Automatic reactivation of TRAC and VSC
Turning the “POWER” switch OFF after turning off the TRAC and VSC systems will
automatically re-enable them.
■Automatic TRAC reactivation
If only the TRAC system is turned off, the TRAC system will turn on when the vehi-
cle speed increases.
■Automatic TRAC and VSC reactivation
If the TRAC and VSC systems are turned off, the systems will not turn on even when
the vehicle speed increases.
■Sounds and vibrations caused by the A BS, brake assist, VSC, TRAC, hill-start
assist control and VGRS systems
●A sound may be heard from the engine compartment when the hybrid system 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 is activated.
• The brake pedal may move down s lightly after the ABS is activated.
■Hill-start assist control operating conditions
This system comes into operation under the following conditions after the brake
pedal has been depressed and the vehicle has come to a stop:
●The shift lever is in the “D” or “S”.
●The system has detected that the vehicle is moving backwards.

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2-4. Using other driving systems
GS_HV_U
January 4, 2008 10:02 am
■Reduced effectiveness of EPS
The effectiveness of EPS 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 hybrid system off. The system should return to normal
about 10 minutes.
■VGRS is disabled in the following situations
●During stopping or the steering wheel has been moved for a long time while
driving at lower speeds.
●After the hybrid system is restarted at less than -22°F (-30°C).
CAUTION
Any of the following conditions may result in an accident which could cause death or
serious injury:
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded.
●The vehicle hydroplanes while driving at high speed on the wet or slick road.
■Stopping distance when the ABS is operating will exceed that of normal condi-
tions
The ABS is not designed to shorten the vehicle’s stopping dist ance. Always main-
tain a safe distance from the vehicle in front of you in the following 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 roads
■TRAC may not operate effectively when
Directional control and power may not be ac hievable while driving on slippery road
surfaces, even if the TRAC is operating. 
Do not drive the vehicle in conditions where stability and power may be lost.

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2-4. Using other driving systems
2
When driving
GS_HV_U
January 4, 2008 10:02 am
CAUTION
■The hill-start assist control may not operate effectively when
●On steep inclines.
●On icy surfaces.
■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 TRAC and VSC are off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are systems to ensure vehicle stability and driving force, do not turn off TRAC
and VSC 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 ti res are inflated to the specified tire pres-
sure level.
The ABS and VSC will not function correctly if different tires are fitted on the vehi-
cle. 
Contact your Lexus dealer for further info rmation when replacing tires or wheels.
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will affect the driv-
ing assist systems, and may cause the system to malfunction.

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4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U
December 27, 2007 1:38 pm
Brake fluid■ Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
Make sure to check the fluid type and prepare the necessary items.
■ Adding fluid
Fluid typeFMVSS No.116 DOT 3 or SAE J1703 brake fluid
ItemsClean funnel
■Brake fluid can absorb moisture from the air
Excess moisture in the fluid can cause a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
CAUTION
■When filling the reservoir
Take care because brake fluid can harm your hands or eyes and damage painted
surfaces. 
If fluid gets in your eyes, flush your eyes with clean water immediately.
If you still experience discomfort, see a doctor.

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4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U
December 27, 2007 1:38 pm
Air conditioning filter
The air conditioning filter must be cleaned or changed regularly to main-
tain air conditioning efficiency.
■ Removal method
Set the air conditio ning system to recirculated mode.
The air conditioning filter case cannot be removed with the system in
the outside air mode.
Turn the “POWER” switch to OFF.
Open the glove box and
remove the partition.
Remove the filter cover.
Press the tabs and remove the
filter case.
STEP1
STEP2
STEP3
STEP4
STEP5

456
4-3. Do-it-yourself maintenance
GS_HV_U
December 27, 2007 1:38 pm
Checking and replacing fuses
If any of the electrical components do not operate, a fuse may have blown.
If this happens, check and replace the fuses as necessary.
Turn the “POWER” switch to OFF.
Remove the engine compartment cover if necessary.
P. 4 2 1
Open the fuse box cover.
■ Engine compartment
Remove the clips.
■ Front controller in the engine compartment fuse box
Lift the lid off while pushing the
tabs on either side.STEP1
STEP2
STEP3