Page 891 of 1014
8647-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
Inte-
rior
buzzerExterior
buzzerWarning messageDetailsCorrection
procedure
Once
Con-
tinu-
ous
An attempt was
made to exit the
vehicle with the
electronic key and
lock the doors
without first turn-
ing the power
switch off when
the shift lever was
in P.
Turn the
power
switch off
and lock
the doors
again.
9
times
An attempt was
made to drive
when the regular
key was not
inside the vehicle.Confirm
that the
electronic
key is
inside the
vehicle.
Con-
tinu-
ous
The driver’s door
was opened when
the shift lever was
not in P and the
power switch was
not turned off.
Shift the
shift lever
to P.
(Displayed alternately)
(Flashes)
(Flashes)
(Flashes)
Page 892 of 1014
8657-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
Inte-
rior
buzzerExterior
buzzerWarning messageDetailsCorrection
procedure
Con-
tinu-
ousCon-
tinu-
ousThe driver’s door
was opened and
closed while the
electronic key
was not in the
vehicle, the shift
lever was not in P
and the power
switch was not
turned off.•Shift the
shift
lever to
P.
•Bring the
elec-
tronic
key back
into the
vehicle.
Once
Con-
tinu-
ous
(Vehicles with the entry
function)
An attempt was
made to lock the
doors using the
smart entry &
start system while
the electronic key
was still inside
the vehicle.Retrieve
the elec-
tronic key
from the
vehicle and
lock the
doors
again.
(Displayed alternately)
(Flashes)
(Flashes)
Page 920 of 1014
8937-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
Inflate the tire until the recom-
mended pressure is reached.
The sealant will be injected
and the pressure will spike to
300 kPa (3.0 kgf/cm
2 or bar,
44 psi) or 400 kPa (4.0 kgf/
cm
2 or bar, 58 psi), and then
gradually decrease.
The air pressure gauge will
display the actual tire infla-
tion pressure about 1 minute
(15 minutes at low tempera-
ture) after the switch is
turned on.
Inject to recommended
pressure.
• Turn the compressor switch
off and then check the tire
inflation pressure. Being
careful not to over inflate,
check and repeat the inflation
procedure until the specified
tire inflation pressure is
reached.
12
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Page 938 of 1014
911
7 7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
Trunk
Turn the mechanical key
clockwise to open.
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Lexus emblem side
of the electronic key to the
power switch.
The power switch will turn to ON
mode.
When the smart entry & start sys-
tem is deactivated in customization
setting, the power switch will turn
to ACCESSORY mode.
Firmly depress the brake pedal and check that is shown on
the multi-information display.
Press the power switch.
In the event that the hybrid system still cannot be started, contact
any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
Starting the hybrid system
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2
3
4
Page 944 of 1014
9177-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
If your vehicle overheats
If the needle of the engine coolant temperature gauge enters the
red zone
Stop the vehicle in a safe place and turn off the air condition-
ing system, and then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
The following may indicate that your vehicle is overheating.
The needle of the engine coolant temperature gauge (P. 109)
enters the red zone or a loss of hybrid system power is experi-
enced. (For example, the vehicle speed does not increase.)
“Hybrid System Overheat” (P. 856) is shown on the multi-
information display.
Steam comes out from under the hood.
Correction procedures
1
2
Page 947 of 1014
9207-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
If “Hybrid System Overheat” is shown on the multi-information
display
Stop the vehicle in a safe place.
Stop the hybrid system and carefully lift the hood.
After the hybrid system has cooled down, inspect the hoses
and radiator core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immediately contact your Lexus
dealer.
The coolant level is satisfactory if it is between the “F”/
“FULL” and “L”/“LOW” lines on the reservoir.
Reservoir
“F”/“FULL”
“L”/“LOW”
1
2
3
1
2
GS300hGS450h
4
1
2
3
GS300hGS450h
Page 949 of 1014
9227-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
Add coolant if necessary.
Water can be used in an emergency if power control unit coolant is
unavailable.
Start the hybrid system and check for the multi-information
display.
If the message does not disappear:
Stop the hybrid system and contact your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest Lexus dealer.
5
GS300hGS450h
6
Page 963 of 1014

9328-1. Specifications
GS450h_300h_OM_OM30D53E_(EE)
Oil viscosity (0W-20 is explained here as an example):
• The 0W in 0W-20 indicates the characteristic of the oil which
allows cold startability. Oils with a lower value before the W
allow for easier starting of the engine in cold weather.
• The 20 in 0W-20 indicates the viscosity characteristic of the
oil when the oil is at high temperature. An oil with a higher
viscosity (one with a higher value) may be better suited if the
vehicle is operated at high speeds, or under extreme load con-
ditions.
How to read oil container labels:
Either or both API registered marks are added to some oil con-
tainers to help you select the oil you should use.
API Service Symbol
Top portion: “API SERVICE
SN” means the oil quality desig-
nation by American Petroleum
Institute (API).
Center portion: “SAE 0W-20”
means the SAE viscosity grade.
Lower portion: “Resource-Con-
serving” means that the oil has
fuel-saving and environmental
protection capabilities.
ILSAC Certification Mark
The International Lubricant
Specification Advisory Com-
mittee (ILSAC) Certification
Mark is displayed on the front
of the container.
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2