2010 Lexus HS250h engine

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2-1. Driving procedures
2
When driving
CAUTION
■When starting the vehicle
Always keep your foot on the brake pedal while stopped with the hybrid system
operating. This prevents the vehicle from creeping.
■When driving the vehicle
●Do not drive if you are unfamiliar with the location of the brake and accelerator
pedals to avoid depressing the wrong pedal.
• Accidentally depressing the accelerator pedal instead of the brake pedal will
result in sudden acceleration that may lead to an accident that could result in
death or serious injury.
• When backing up, you may twist your body around, leading to a difficulty in
operating the pedals. Make sure to operate the pedals properly.
• Make sure to keep a correct driving posture even when moving the vehicle only slightly. This allows you to depress the brake and accelerator pedals
properly.
• Depress the brake pedal using your right foot. Depressing the brake pedal using your left foot may delay response in an emergency, resulting in an acci-
dent.
●The driver should pay extra attention to pedestrians when the vehicle is powered
only by the electric motor (traction motor). Because there is no engine noise, the
pedestrians may misjudge the vehicle’s movement.
●Do not drive the vehicle over or stop the vehicle near flammable materials. 
The exhaust system and exhaust gases can be extremely hot. These hot parts may
cause a fire if there is any flammable material nearby.
●Do not let the vehicle roll backward whil e a forward driving position is selected,
or roll forward while R is selected. 
Doing so may result in an acci dent or damage to the vehicle.
●If the smell of exhaust is noticed inside the vehicle, open the windows and check
that the trunk is closed. Large amounts of exhaust in the vehicle can cause driver
drowsiness and an accident, resulting in death or a serious health hazard. Have
the vehicle inspected by your Lexus dealer immediately.
●Do not shift the shift position to P while the vehicle is moving. 
Doing so can damage the transmission and may result in a loss of vehicle control.
●Do not shift the shift position to R while the vehicle is moving forward. 
Doing so can damage the transmission and may result in a loss of vehicle control.

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2-1. Driving procedures
CAUTION
●Do not shift the shift position to D while the vehicle is moving backward.
Doing so can damage the transmission and may result in a loss of vehicle control.
●Moving the shift position to N while the vehicle is moving will disengage the
hybrid system. Engine braking is not avai lable with the hybrid system disengaged.
●During normal driving, do not turn off the hybrid system. Turning the hybrid sys-
tem off while driving will not cause loss of steering or braking control, but the
power assist to these systems will be lost. Th is will make it more difficult to steer
and brake, so you should pull over and stop the vehicle as soon as it is safe to do
so. However, in the event of an emergency, such as if it becomes impossible to
stop the vehicle in the normal way: P. 4 9 2
●Use engine braking (shift position B) to maintain a safe speed when driving down
a steep hill. 
Using the brakes continuously may cause the brakes to overheat and lose effec-
tiveness. ( P. 1 5 3 )
●Do not adjust the positions of the steering wheel, the seat, or the inside or outside
rear view mirrors while driving. 
Doing so may result in a loss of vehicle control that can cause accidents, resulting
in death or serious injury.
●Always check that all passengers' arms, he ads or other parts of their body are not
outside the vehicle, as this may result in death or serious injury.
●Do not drive in excess of the speed limit. Even if the legal speed limit permits it, do
not drive over 85 mph (140 km/h) unless your vehicle has high-speed capability
tires. Driving over 85 mph (140 km/h) may result in tire failure, loss of control and
possible injury. Be sure to consult a tire dealer to determine whether the tires on
your vehicle are high-speed capability tires or not before driving at such speeds.
■When driving on slippery road surfaces
●Sudden braking, accelerati on and steering may cause tire slippage and reduce
your ability to control the vehi cle, resulting in an accident.
●Abrupt changes from shift position D to B and rapid changes in the engine speed
could cause the vehicle to skid, resulting in an accident.
●After driving through a puddle , lightly depress the brake pedal to make sure that
the brakes are functioning properly. Wet brake pads may prevent the brakes from
functioning properly. If the brakes on on ly one side are wet and not functioning
properly, steering control may be af fected, resulting in an accident.

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2-1. Driving procedures
2
When driving
CAUTION
■When changing the shift position
Be careful not to change the shift position with the accelerator pedal depressed. 
Changing the shift position to any positions other than P or N may cause the vehicle
to accelerate abruptly, causing an accident and resulting in death or serious injury.
■If you hear a squealing or scraping no ise (brake pad wear limit indicators)
Have your Lexus dealer check and replac e the brake pads as soon as possible. 
Rotor damage may result if the pa ds are not replaced when needed.
It is dangerous to drive the vehicle when the wear limits of the brake pads and/or
those of the brake discs are exceeded.
■When the vehicle is stopped
●Do not depress the accelerator pedal unnecessarily. 
If the vehicle is in any shift position other than P or N, the vehicle may accelerate
suddenly and unexpectedly , causing an accident.
●Do not leave the vehicle with the hybrid system on for a long time. 
If such a situation cannot be avoided, park the vehicle in an open space and
check that exhaust fumes do no t enter the vehicle interior.
●In order to prevent accidents due to the vehicle rolling away, always keep
depressing the brake pedal while the “READY” indicator is on. Apply the parking
brake as necessary.
●If the vehicle is stopped on an incline, in order to prevent accidents caused by the
vehicle rolling forward or backward, always depress the brake pedal and securely
apply the parking brake as needed.
●Avoid revving or racing the engine. 
Running the engine at high speed while the vehicle is stopped may cause the
exhaust system to overheat, which could result in a fire if combustible material is
nearby.
■When the vehicle is parked
●Do not leave glasses, cigarett e lighters, spray cans, or soft drink cans in the vehi-
cle when it is in the sun. 
Doing so may result in the following:
• Gas may leak from a cigarette lighter or spray can, and may lead to a fire.
• The temperature inside the vehicle may cause the plastic lenses and plastic material of glasses to deform or crack.

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2-1. Driving procedures
NOTICE
■Avoiding damage to vehicle parts
●Do not turn the steering wheel fully in either direction and hold it there for an
extended period of time. 
Doing so may damage the power steering motor.
●When driving over bumps in the road, drive as slowly as possible to avoid damag-
ing the wheels, underside of the vehicle, etc.
■If you get a flat tire while driving
A flat or damaged tire may cause the following situations. Hold the steering wheel
firmly and gradually depress the brak e pedal to slow down the vehicle.
●It may be difficult to control your vehicle.
●The vehicle will make abnormal sounds or vibrations.
●The vehicle will lean abnormally.
Information on what to do in case of a flat tire. ( P. 5 2 1 )
■When encountering flooded roads
Do not drive on a road that has flooded after heavy rain etc. Doing so may cause the
following serious damage to the vehicle:
●Engine stalling
●Short in electrical components
●Engine damage caused by water immersion
In the event that you drive on a flooded road and the vehicle is flooded, be sure to
have your Lexus dealer check the following:
●Brake function
●Changes in quantity and quality of engine oil, transaxle fluid for the hybrid system
etc.
●Lubricant condition for the bearings and suspension joints (where possible), and
the function of all joints, bearings, etc.
As flooding may damage components involv ed in P position control, the parking
lock may jam in the locked position.
■If the vehicle will not shift out of the P position
There is a possibility that the 12-volt batt ery is discharged. Check the 12-volt battery
in this situation.

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2-1. Driving procedures
2
When driving
Power (ignition) switch
Performing the following operations when carrying the electronic key on
your person starts the hybrid system or changes “POWER” switch modes.
■Starting the hybrid system
Check that the parking brake is set.
Firmly depress the brake pedal.
The “POWER” switch indicator will turn green. If the indicator does
not turn green, the hybrid system cannot be started.
When shift position N is selected, the hybrid system cannot start.
Select the P position when star
ting the hybrid system.
Press the “POWER” switch.
After a while, the “READY” indi -
cator comes on with a beep
sound.
The vehicle can move when the
“READ
Y” indicator is on even if
the engine is stopped.
Continue depressing the brake
pedal
until the hybrid system is
completely started.
The hybrid system can be
star
ted from any mode.

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2-1. Driving procedures
EV drive mode
In EV drive mode, the electric motor (traction motor), powered by the
hybrid battery (traction battery), is used to drive the vehicle.
This mode allows you to drive in residential areas late at night, or in indoor
parking lots etc. without concern fo r noises and exhaust gas emissions.
Turns EV drive mode on/off
When EV drive mode is turned
on, the EV drive mode indicator
will come on. Pressing the
switch when in EV drive mode
will return the vehicle to normal
driving (using the gasoline
engine and electric motor [trac-
tion motor]).

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2-1. Driving procedures
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When driving
■Situations in which EV drive mode cannot be turned on
It may not be possible to turn EV drive mode on in the following situations. If it can -
not be turned on, a buzzer will sound and a message will be shown on the multi-
info
rmation display.
●Engine coolant temperature is low.
●Vehicle speed is about 19mph (30km/h) or more.
●The hybrid battery (traction battery) is low. 
An “Energy Monitor” display of level 3 or lower may indicate a low battery level.
(  P. 3 2 )
● The temperature of the hybrid system is high. 
The vehicle has been left in the sun, driv en on a
hill, driven at high speeds, etc.
●The temperature of the hybrid system is low. 
The vehicle has been left in temperatures lower than about 32°F (0°C) for a
l
ong period of time etc.
●The gasoline engine is warming up.
●The accelerator pedal is depressed firmly or the vehicle is on a hill etc.
●The windshield defogger is in use.
■Automatic cancellation of EV drive mode
When driving in EV drive mode, the gasoline engine may automatically restart in
the
following situations. When EV drive mo de is canceled, a buzzer will sound and
the EV drive mode indicator will flash and go off.
●The hybrid battery (traction battery) becomes low. 
The remaining battery level indicated in the “Energy Monitor” display is level 2
or lo
wer. ( P. 3 2)
●Vehicle speed becomes more than about 19 mph (30 km/h).
●The accelerator pedal is depressed firmly or the vehicle is on a hill etc.
When it is possible to inform the driver o
f automatic cancellation in advance, a prior
notice screen will appear on the multi-information display.
■ Possible driving distance when driving in EV drive mode
In EV drive mode, it is possible to drive up to about several hundred yards if driving
at
a speed of about 19 mph (30 km/h) or less. (The distance that is possible
depends on the hybrid battery [traction battery] level and driving conditions.)

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2-1. Driving procedures
■Fuel economy
HS250h is designed to achieve the best possible fuel economy during normal driv-
ing (using the gasoline engine and electric motor [traction motor]). Driving in EV
drive mode more than necessary may lower fuel economy.
CAUTION
■Caution while driving
When driving in EV drive mode, pay special attention to the area around the vehi-
cle. Because there is no engine noise, pedestrians, people riding bicycles or other
people and vehicles in the area may not be aware of the vehicle starting off or
approaching them, so take extra care while driving.