2011 Lexus HS250h cooling

26
1-1. Hybrid system
■Charging the battery
As the gasoline engine charges the hybrid battery (traction battery), the battery
does not need to be charged from an outside source. However, if the vehicle is left
parked for a long time the hybrid battery will slowly discharge. For this reason, be
sure to drive the vehicle at least once every few months for at least 30 minutes or
10 miles (16 km). If the hybrid battery becomes fully discharged and you are unable
to jump-start the vehicle with the 12-v olt battery, contact your Lexus dealer.
■After the 12-volt battery has discharged or has been changed or removed
The gasoline engine may not stop even if the vehicle is running on the hybrid battery
(traction battery). If this continues for a few days, contact your Lexus dealer.
■Sounds and vibrations specific to a hybrid vehicle
There may be no engine sounds or vibrat ion even though the vehicle is able to
move. Always change the shift position to P, and apply the parking brake when
parked.
The following sounds or vibrations may occur when the hybrid system is operating
and are not a malfunction:
●Motor sounds may be heard fr om the engine compartment.
●Sounds may be heard from the hybrid ba ttery (traction battery) behind the rear
seats when the hybrid system starts or stops.
●Sounds from the hybrid system may be heard when the trunk lid is open.
●Sounds may be heard from the transaxle when the engine is started or stopped,
or while the engine is idling.
●Engine sounds may be heard when accelerating sharply.
●Sounds may be heard due to regenera tive braking when the brake pedal is
depressed and accelerator is loosened.
●Other sounds, such as motors and mechanical noises, may be heard from the
brake system when the brake pedal is depressed.
●Vibration may be felt when the gasoline engine starts or stops.
●Cooling fan sounds may be heard from the air intake vent on the side of rear left
seatback.
When driving in Eco drive mode, the fan noise may be louder than when driving
normally.

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1-1. Hybrid system
1
Before driving
Hybrid battery air ventThere is an air intake vent on the
side of the rear left seatback for
the purpose of cooling the hybrid
battery (traction battery). If the
vent become blocked, the hybrid
battery may overheat, leading to a
reduction in hybrid battery output.
Emergency shut off system When a certain level of impact is detected by the impact sensor, the
emergency shut off system blocks off the high voltage current and stops
the fuel pump to minimize the risk of electrocution and fuel leakage. If the
emergency shut off system activates, your vehicle will not restart. To
restart the hybrid system, contact your Lexus dealer.
Hybrid warning message
A message is automatically displayed when a malfunction occurs in the
hybrid system or an impr oper operation is attempted.
If a warning message is shown on
the multi-information display, read
the message and follow the
instructions.
(P. 507)

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1-1. Hybrid system
Hybrid vehicle driving tips
For economical and ecological driving, pay attention to the following
points:
■Using Eco drive mode
When using Eco drive mode, the torq ue corresponding to the accelerator
pedal depression amount can be generated more smoothly than it is in
normal conditions. In addition, the op eration of the air conditioning system
(heating/cooling) will be minimized, improving the fuel economy.
( P. 1 5 7 )
■Use of Hybrid System Indicator
The environmentally-friendly driving is possible by keeping the indicate of
Hybrid System Indicator within Eco area. ( P. 1 6 6 )
■When braking the vehicle
Make sure to operate the brakes ge ntly and in good time. A greater
amount of electrical energy can be retained when slowing down.
■ Delays
Repeated acceleration and deceleration, as well as long waits at traffic
lights, will lead to bad fu el consumption. Check traffic reports before leav-
ing and avoid delays as much as possible. When encountering a delay,
gently release the brake pedal to allow the vehicle to move forward slightly
while avoiding overuse of the accelerato r pedal. Doing so can help control
excessive gasoline consumption.
■ Highway driving
Control your speed and keep at a constant speed. Also, before stopping at
a toll booth or similar, allow plenty of time to release the accelerator and
gently apply the brakes. A greater amount of electrical energy can be
retained when slowing down.

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2-1. Driving procedures
2
When driving
■Selecting a driving mode
The following modes can be selected to suit driving conditions:
Eco drive mode
Suitable for improving the fuel
economy, because the torque
corresponding to the accelera-
tor pedal depression amount
can be generated more
smoothly than it is in normal
conditions and the operation of
the air conditioning system
(heating/cooling) will be mini-
mized.
When the “ECO MODE”
switch is pressed, the “ECO
MODE” indicator comes on in
the meter.
Power mode
Suitable when the vehicle needs
to drive powerfully or travels in
mountainous areas.
When the power mode switch is
pressed, the “PWR MODE”
indicator comes on in the meter.

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2-1. Driving procedures
2
When driving
■Using air conditioning in Eco drive mode
The Eco drive mode controls heating/cooling and fan speed operation to improve
fuel consumption. When you want to improve the effectiveness of the air condition-
ing system, adjust the fan speed or cancel the Eco drive mode.
For more information, refer to the “Navigation System Owner’s Manual”.
■Power mode automatic deactivation
Power mode is automatically deactivated if the “POWER” switch is turned off after
driving in power mode.
■Customization
Settings (e.g. Reverse warning buzzer) can be changed.
(Customizable features  P. 5 8 0 )
CAUTION
■When driving on slippery road surfaces
Do not accelerate or shift gears suddenly.
Sudden changes in engine braking may cause the vehicle to spin or skid, resulting in
an accident.
■For the shift lever
Do not hang anything on the shift lever.
Doing so could prevent the shift lever fr om returning to position, causing unex-
pected accidents to occur when the vehicle is in motion.

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3-1. Using the air conditioning system and defogger
Automatic air conditioning system
Air outlets and fan speed are automati cally adjusted according to the tem-
perature setting.
Vehicles with a navigation system
Owners of models equi pped with a navigation system should refer to
the “Navigation System Owner’s Manual”.
Vehicles without a navigation system
Automatic
mode button
Driver’s side
temperature display
Dual
mode
button
Fan speed control buttons Air outlet display
Fan speed display
Passenger’s side
temperature display
Driver’s side
temperature
control buttons Outside/recirculated air
mode buttonWindshield
defogger button Passenger’s side
temperature
control buttons
Micro dust
and pollen
filter mode
button
“OFF” button Air outlet selector button
Cooling and
dehumidification
function on/off
button

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3-1. Using the air conditioning system and defogger
■Using the system in recirculated air mode
The windows will fog up more easily if recirculated air mode is used.
■Window defogger feature
Recirculated air mode may automatically switch to (outside air) mode in sit-
uations where the windows need to be defogged.
■When micro dust and pollen filter is active
●In order to prevent the windshield from fogging up when the outside air is cold,
the following may occur:
• Outside air mode does not switch to (recirculated air) mode.
• The air conditioning syst em operates automatically.
• The operation cancels after 1 minute.
●In rainy weather, the windows may fog up. Press .
■When outside air temperature is below 32 F (0C)
The cooling and dehumidification func tion may not operate even when
is
pressed.
■Air conditioning odors
●During use, various odors from inside and outside the vehicle may enter into
and accumulate in the air conditioning sy stem. This may then cause odor to be
emitted from the vents.
●To reduce potential odors from occurring:
• It is recommended that the air conditioning system be set to outside air mode
prior to turning the vehicle off.
• The start timing of the blower may be delayed for a short period of time immediately after the air conditioning system is started in automatic mode.
CAUTION
■To prevent the windshield from fogging up
Do not use
during cool air oper ation in extremely humid weather. The dif-
ference between the temperature of the outside air and that of the windshield can
cause the outer surface of the windshield to fog up, blocking your vision.

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4-3. Do-it-yourself maintenance
CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious injury,
observe the following precautions:
■When working on the engine compartment
●Make sure that the indicator on the “POWER” switch and the “READY” indicator
are both off.
●Keep hands, clothing and tools away from the moving fans and engine drive belt.
●Be careful not to touch the engine, power control unit, radiator, exhaust manifold,
etc. right after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flam-
mable.
■When working near the electric cooling fans or radiator grille
Be sure the “POWER” switch is off.
With the “POWER” switch in ON mode, the electric cooling fans may automati-
cally start to run if the air conditioning is on and/or the coolant temperature is high.
(  P. 4 3 6 )
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting
in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to
dirt in the air. Also, a backfire could cause a fire in the engine compartment.