2010 Lexus HS250h heating

31
1-1. Hybrid system
1
Before driving
CAUTION
●If your vehicle needs to be towed, do so with front wheels raised. If the wheels
connected to the electric motor (traction motor) are on the ground when towing,
the motor may continue to generate electricity. This may cause an electricity
leakage leading to a fire. (
P. 4 8 3 )
●Carefully inspect the ground under the vehicle. If you find that liquid has leaked
onto the ground, the fuel system may have been damaged. Leave the vehicle as
soon as possible.
■Nickel-metal hydride battery
Your vehicle contains a sealed nickel-metal hydride battery. If disposed of improp-
erly, it is hazardous to the environment and there is a risk of severe burns and elec-
trical shock that may result in death or serious injury.
■Emergency shut off system
Carefully check to see if there are exposed high voltage parts or cables. Never
touch the parts or cables. (
P. 2 7 )
NOTICE
■Hybrid battery air vent
●Do not put foreign objects near the air ve nt. The hybrid battery (traction battery)
may overheat and be damaged.
●Clean the air vent regularly to prevent th e hybrid battery (traction battery) from
overheating.
●Do not wet or allow foreign substances to enter the air vent as this may cause a
short circuit and damage the hybrid battery (traction battery).
●Do not carry large amounts of water such as water cooler bottles in the vehicle. If
water spills onto the hybrid battery (traction battery), the battery may be dam-
aged. Have the vehicle inspected by your Lexus dealer.

143
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 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 and 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.

160
2-1. Driving procedures
Parking brake
■Parking brake engaged warning buzzer
The buzzer sounds to indicate that parking b
rake is still engaged (with the vehicle
having reached a speed of 3 mph [5 km/h]). ( P. 5 0 6 )
NOTICE
■Before driving
Fully release the parking brake. 
Driving the vehicle with the parking brake set will lead to brake components over-
heating, which may affect braking performance and increase brake wear.
To set the parking brake, fully
depress the parking brake pedal
with your left foot while
depressing the brake pedal with
your right foot.

(Depressing the pedal again
r

eleases the parking brake.)
U.S.A.Canada

164
2-2. Instrument cluster
■Limitations of brightness adjustment
The brightness of the instrument panel lights is automatically adjusted based on the
light sensor detecting how bright the surroundings are. However, if the instrument
panel brightness has been manually set to either the brightest or dimmest setting,
the automatic adjustment will not be performed.
■Hybrid System Indicator
●By keeping the indicator needle within Eco area, environmentally-friendly driv-
ing can be achieved.
Hybrid Eco area shows that gasoline engine power is not being used very often.*
1
●Charge area indicates regeneration*2 status. Regenerated energy will be used
to charge the hybrid battery.
*
1: The gasoline engine will automatically stop and restart under various condi- tions.
*
2: When used in this manual, “regeneration” refers to the conversion of energy created by the movement of the vehicle into electrical energy.
■Customization
Settings (e.g. Sensitivity of the ambient light sensor used for dimming the meter
lights) can be changed. (Customizable features P. 5 7 2 )
NOTICE
■To prevent damage to the hybrid system and its components
A high engine coolant temperature warning light ( P. 492) is installed instead of
an engine coolant temperature gauge. If the high engine coolant temperature
warning light illuminates or flashes, the vehicle may be overheating. Immediately
stop the vehicle in a safe area ( P. 5 4 1 ) .
Eco area 
Eco Driving Indicator Light comes on
Hybrid Eco area 
Eco Driving Indicator Light comes on
Charge area 
Eco Driving Indicator Light comes on
Po w e r a r e a 
Eco Driving Indicator Light turns off

228
2-4. Using other driving systems
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from over-
heating 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 EPS system
should return to normal within 10 minutes.
CAUTION
■The ABS does not operate effectively when
●Tires with inadequate gripping ability are used (such as excessively worn tires on
a snow covered road).
●The vehicle hydroplanes while driving at high speed on 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 surfaces
■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 system is operating. 
Do not drive the vehicle in conditions where stability and power may be lost.
■When the VSC is activated
The slip indicator light flashes and a warning buzzer sounds. Always drive carefully.
Reckless driving may cause an accident. Exercise particular care when the indica-
tor light flashes and a buzzer sounds.
■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 ensure vehicle stability and driving force, do not turn the
TRAC/VSC systems off unless necessary.

376
3-7. Other interior features
CAUTION
■Burns
●Use caution when seating the following persons in a seat with the seat heater on
to avoid the possibility of burns:
• Babies, small children, the elderly, the sick and the physically challenged
• Persons with sensitive skin
• Persons who are fatigued
• Persons who have taken alcohol or dr ugs that induce sleep (sleeping drugs,
cold remedies, etc.)
●Do not cover the seat with anything when using the seat heater.
Using the seat heater with a blanket or cushion increases the temperature of the
seat and may lead to overheating.
●Do not use the seat heater more than necessary. Doing so may cause minor
burns or overheating.
NOTICE
■To prevent damage to the seat heaters/ventilators
Do not put heavy objects that have an unev en surface on the seat and do not stick
sharp objects (needles, nail s, etc.) into the seat.
■To prevent 12-volt battery discharge
Turn the seat heaters/ventilators off when the hybrid system is off.

5
When trouble arises
493
5-2. Steps to take in an emergency
Have the vehicle inspected by your Lexus dealer immediately.
Failing to investigate the cause of the following warnings may lead to the
system operating abnormally and possibly cause an accident. Have the
vehicle inspected by your Lexus dealer immediately.
High engine coolant temperatur e warning light (flashes or
comes on) Indicates that the engine is overheating P. 5 4 1
• Flashes: Engine is overheating. Drive carefully.
• Comes on: Engine is overheated. Stop the vehicle.
Warning lightWarning light/Details
Brake system warning light (yellow indicator) Indicates a malfunction in:
• The regenerative brake system; or
• The electronically controlled brake system
(U.S.A.)

(Canada)
Malfunction indicator lamp
Indicates a malfunction in:
• The hybrid system;
• The electronic engine control system;
• The electronic throttle control system; or
• The hybrid transmission control system
SRS warning lightIndicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system
(U.S.A.)

(Canada)
“ABS” warning lightIndicates a malfunction in:
•The ABS; or
• The brake assist system
Warning lightWarning light/Details

5
When trouble arises
507
5-2. Steps to take in an emergency
(U.S.A. only)
Indicates that the engine
oil should be changedComes on approxi-
mately 5000 miles
(8000 km) after the
engine oil is changed
(and the oil maintenance
data has been reset)
Check and change the
engine oil.
Indicates that the tire
inflation pressure is lowCheck the tire inflation
pressure, and adjust to the
appropriate level.
(If equipped)
Indicates that the pre-
collision system is not
currently functional
because the grille or the
sensor is dirty.
This message also
appears when the pre-
collision system is not
functional due to over-
heating.
Check the grille and the
sensor and clean them if
they are dirty.In case of overheating,
the system will become
functional once the sys-
tem cools down.
(If equipped)
Indicates that intuitive
parking assist sensor is
dirty or covered with ice
A buzzer also sounds.
The site of the malfunc-
tion and the vehicle
image are flashing.
Clean the sensor.
Wa r n i n g m e s s a g eDetailsCorrection procedure