2013 Lexus GS300h cooling

831-2. Hybrid system
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GS450h_300h_OM_OM30D53E_(EE)
For safety and security
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 any autho-
rized Lexus dealer or repairer, or another duly qualified and equipped profes-
sional.
Sounds and vibrations specific to a hybrid vehicle
There may be no engine sounds or vibration even though the vehicle is able
to move. For safety, apply the parking brake and make sure to shift the shift
position to P 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 from the engine compartment.
Sounds may be heard from the hybrid battery (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 hybrid transmission when the hybrid system
starts or stops.
Engine sounds may be heard when accelerating sharply.
Sounds may be heard due to regenerative braking 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 vents on the both sides
of the rear seatback.
Maintenance, repair, recycling, and disposal
Contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional regarding maintenance, repair, recycling and dis-
posal. Do not dispose of the vehicle yourself.
Customization
Settings (e.g. on/off operation of the EV indicator) can be changed.
(Customizable features: P. 942)

851-2. Hybrid system
1
GS450h_300h_OM_OM30D53E_(EE)
For safety and security
There are air intake vents on the
both sides of the rear seatback
for the purpose of cooling the
hybrid battery (traction battery).
If the vents become blocked, the
hybrid battery may overheat,
leading to a reduction in hybrid
battery output.
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 any authorized
Lexus dealer or repairer, or another duly qualified and equipped
professional.
A message is automatically displayed when a malfunction occurs in
the hybrid system or an improper operation is attempted.
If a warning message is shown
on the multi-information display,
read the message and follow the
instructions.
(P. 838)
Hybrid battery (traction battery) air vents
Emergency shut off system
Hybrid warning message

3964-5. Using the driving support system
GS450h_300h_OM_OM30D53E_(EE)
Operation of the air conditioning system in Eco drive mode
Eco drive mode controls the heating/cooling operations and fan speed of the
air conditioning system to enhance fuel efficiency (P. 478). To improve air
conditioning performance, adjust the fan speed or turn off Eco drive mode.
Automatic operation of the seat heater during Eco drive mode
Eco drive mode controls the heating operation and fan speed of the air condi-
tioning system to enhance fuel efficiency. If the driving mode select switch is
switched to Eco drive mode in cold temperatures, the seat heater will be auto-
matically operated to assist heating performance.
Sport mode automatic deactivation
Sport mode is automatically deactivated if the power switch is turned off
after driving in sport mode.
Operation of the Eco drive mode (on some models)
The driving mode will set to Eco drive mode each time the power switch is
turned to ON mode.

4324-6. Driving tips
GS450h_300h_OM_OM30D53E_(EE)
Hybrid vehicle driving tips
Using Eco drive mode
When using Eco drive mode, the torque corresponding to the
accelerator pedal depression amount can be generated more
smoothly than it is in normal conditions. In addition, the opera-
tion of the air conditioning system (heating/cooling) will be min-
imized, improving the fuel economy. (P. 392)
Use of Hybrid System Indicator
The Eco-friendly driving is possible by keeping the indicate of
Hybrid System Indicator within Eco area. (P. 126)
When braking the vehicle
Make sure to operate the brakes gently 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 fuel consumption. Check traffic
reports before leaving 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 over-
use of the accelerator 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
For economical and ecological driving, pay attention to the follow-
ing points:

4815-2. Using the air conditioning system and defogger
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Interior features
GS450h_300h_OM_OM30D53E_(EE)
*: nanoe™ and the nanoe™ mark are trademarks of Panasonic Corporation.
Fan speed control
Air flows to the feet and the
windshield defogger operates
Outside temperature
Right-hand front seat side
temperature control
Right-hand front seat side
temperature display
Front seat air outlet selector
nanoe
* system (if
equipped)
Pollen removal mode
DUAL/3-ZONE mode
Cooling and dehumidifica-
tion function on/off
Left-hand front seat side tem-
perature displayLeft-hand front seat side tem-
perature control
Windshield defogger
Outside air or recirculated
mode
Air outlet selector
S-FLOW mode
Off
Automatic mode
Left-hand front seat side air
outlet selector
Rear air conditioning opera-
tion screen
Right-hand front seat side air
outlet selector
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4925-2. Using the air conditioning system and defogger
GS450h_300h_OM_OM30D53E_(EE)
The windows may fog up if the recirculated air mode is used.
Outside/recirculated air mode
When driving on dusty roads such as tunnels or in heavy traffic, set the out-
side/recirculated air mode button to the recirculated air mode. This is effec-
tive in preventing outside air from entering the vehicle interior. During
cooling operation, setting the recirculated air mode will also cool the vehi-
cle interior effectively.
Outside/recirculated air mode may automatically switch depending on the
temperature setting or the inside temperature.
Automatic mode for air intake control
In automatic mode, the system detects exhaust gas and other pollutants and
automatically switches between outside air and recirculated air modes.
When the dehumidification function is off, and the fan is operating, turning
automatic mode on will activate the dehumidification function.
Pollen removal mode
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 dehumidification function operates.
• The operation cancels after approximately 1 minute.
In rainy weather, the windows may fog up. Press .
In extremely humid weather, the windows may fog up.
The pollens are filtered out even if the pollen removal mode is turned off.
Operation of the air conditioning system in Eco drive mode
In the Eco drive mode, the air conditioning system is controlled as follows to
prioritize fuel efficiency:
Engine speed and compressor operation controlled to restrict heating/cool-
ing capacity
Fan speed restricted when automatic mode is selected
To improve air conditioning performance, perform the following opera-
tions:
Adjust the fan speed
Turn off Eco drive mode
When the S-FLOW mode operates
If air flows to the driver’s seat only, the temperature setting for the front pas-
senger’s seat is not displayed.
When the outside temperature falls to nearly 0C (32F)

733 6-3. Do-it-yourself maintenance
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Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
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 automat-
ically start to run if the air conditioning is on and/or the coolant temperature
is high.
(P. 747)
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.
If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads
wear or when the fluid level in the accumulator is high.
If the reservoir needs frequent refilling, it may indicate a serious problem.

7386-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Engine compartment
GS300h
12-volt battery
P. 7 4 9
Power control unit coolant
reservoir (P. 745)
Engine oil level dipstick
(P. 741)
Engine oil filler cap (P.
742)
Engine coolant reservoir
(P. 744)Fuse box (P. 782)
Washer fluid tank (P. 748)
Electric cooling fans
Condenser (P. 747)
Radiator (P. 747)1
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