2011 Lexus HS250h Do-it-yourself maintenance / LEXUS 2011 HS250H OWNERS MANUAL (OM75037U)

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2-1. Driving procedures
2
When driving
CAUTION
■When taking a nap in the vehicle
Always turn the hybrid system off. Otherwise, if you accidentally move the shift
lever or depress the accelerator pedal, this could cause an accident or fire due to
hybrid system overheating. Additionally, if the vehicle is parked in a poorly venti-
lated area, exhaust gases may collect and enter the vehicle, leading to death or a
serious health hazard.
■When braking
●When the brakes are wet, drive more cautiously.
Braking distance increases when the brakes are wet, and this may cause one side
of the vehicle to brake differently than the other side. Also, the parking brake may
not securely hold the vehicle.
●If the power brake assist function does not operate, do not follow other vehicles
closely and avoid downhill or sharp turns that require braking.
In this case, braking is still possible, but it will require more force on the pedal than
usual. Braking distance may also increase.
●The brake system consists of 2 individual hydraulic systems; if one of the systems
fails, the others will still operate. In th is case, the brake pedal should be depressed
more firmly than usual and the braking distance will increase. If this happens, do
not continue to drive the vehicle. If the brake system warning light (red indicator)
comes on while driving, immediately stop the vehicle in a safe place and contact
your Lexus dealer.
NOTICE
■When driving the vehicle
●Do not depress the accelerator and brake pe dals at the same time during driving.
If the brake pedal is depressed whil e driving with the accelerator pedal
depressed, driving torque may be restrained.
●Do not use the accelerator pedal or depress the accelerator and brake pedals at
the same time to hold the vehicle on a hill.
■When parking the vehicle
Be sure to firmly apply the parking brake an d set the shift position to P. Failure to do
so may cause the vehicle to move or the vehicle may accelerate suddenly if the
accelerator pedal is accidentally depressed.

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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 7 )
■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 starting 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
“READY” 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
started from any mode.

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2-1. Driving procedures
■Stopping the hybrid system
Stop the vehicle by depressing the brake pedal.
Set the parking brake. ( P. 162)
Press the P position switch to shift into P. ( P. 1 5 6 )
Check that the shift position indicator on the instrument cluster
shows P. ( P. 1 5 5 )
Press the “POWER” switch.
Slowly release the brake pedal and check that the indicator on
the “POWER” switch is off.
■ Changing “POWER” switch modes
Modes can be changed by pressing the “POWER” switch with the
brake pedal released. (The mode changes each time the switch is
pressed.)
Off
The emergency flashers can be
used.
ACCESSORY mode
Some electrical components
such as the audio system can be
used.
The “POWER” switch indicator
turns amber.
ON mode
All electrical components can
be used.
The “POWER” switch indicator
turns amber.

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2-1. Driving procedures
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When driving
■Auto power off function
If the vehicle is left in ACCESSORY or ON mode (the hybrid system is not operat-
ing) for more than an hour with the shift position in P, the “POWER” switch will
automatically turn off. However, this function cannot entirely prevent the 12-volt
battery from discharging. Do not leave the vehicle with the “POWER” switch in
ACCESSORY or ON mode for long periods of time when the hybrid system is not
operating.
■Sounds and vibrations specific to a hybrid vehicle
 P. 2 6
■Electronic key battery depletion
P. 5 3
■When the ambient temperature is low, such as during winter driving conditions
It may take time until the “READY” indicator to come on.
■Conditions affecting operation
P. 5 0
■Notes for the entry function
P. 5 1
■If the hybrid system does not start
The immobilizer system may not have been deactivated. ( P. 9 8 )
■When the “POWER” switch indicator flashes in amber
The system may be malfunctioning. Have the vehicle inspected by your Lexus
dealer immediately.
■If the “READY” indicator does not come on
If the “READY” indicator does not come on when you press the “POWER” switch
with the shift position in P and the brake pedal depressed, contact your Lexus
dealer immediately.
■If the hybrid system is malfunctioning
P. 5 0 7
■If the electronic key battery is depleted
P. 4 5 9

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2-1. Driving procedures
■Operation of the “POWER” switch
●When operating the “POWER” switch, one short, firm press is enough. If the
switch is pressed improperly, the hybrid system may not start or the “POWER”
switch mode may not change. It is not necessary to press and hold the switch.
●If attempting to restart the hybrid system immediately after turning the
“POWER” switch off, the hybrid system may not start in some cases. After turn-
ing the “POWER” switch off, please wait a few seconds before restarting the
hybrid system.
■Automatic P position selection function
●When the shift position is in a positi on other than P, pressing the “POWER”
switch with the vehicle stopped comple tely will cause the shift position to
change to P automatically, and then the “POWER” switch will turn off.
●When turning the “POWER” switch off from a position other than P, firmly
depress the brake pedal and confirm that the shift position* has changed to P
before slowly releasing the brake pedal.
*: Even after the instrument panel display has been turned off, the shift position
indicator will continue to be displayed for several seconds.
●If the P position control system malfun ctions, the “POWER” switch will not be
able to be turned off. In such a case, the switch can be turned off by applying the
parking brake.
When the system malfunctions, immediately have your vehicle serviced by your
Lexus dealer.
CAUTION
■When starting the hybrid system
Always start the hybrid system while sitting in the driver’s seat. Do not depress the
accelerator pedal while starting the hybrid system under any circumstances.
Doing so may cause an accident resu lting in death or serious injury.
■Stopping the hybrid system in an emergency
If you want to stop the hybrid system in an emergency while driving the vehicle,
press and hold the “POWER” switch for more than 3 seconds.
However, do not touch the “POWER” switch while driving unless in an emergency.
If the hybrid system stops while driving, th is could lead to an unexpected accident.

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2-1. Driving procedures
2
When driving
NOTICE
■To prevent 12-volt battery discharge
●Do not leave the “POWER” switch in ACCESSORY or ON mode for long peri-
ods of time without the hybrid system on.
●If the hybrid system is off, but the indicator on the “POWER” switch is illuminated,
this indicates that the “POWER” switch is still turned on. When exiting the vehi-
cle, always check that the “POWER” switch is off.
■When starting the hybrid system
Do not depress the accelerator pedal unnecessarily.
■Symptoms indicating a malfunction with the “POWER” switch
If the “POWER” switch seems to be operating somewhat differently than usual,
such as the switch sticking slightly, there may be a malfunction. Contact your Lexus
dealer immediately.

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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]).