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497
8When trouble arises
IS300h_EE(OM53B95E)
8-1. Essential information
Emergency flashers ........... 498
If your vehicle has to be
stopped in an
emergency ....................... 4998-2. Steps to take in an
emergency
If your vehicle needs to
be towed.......................... 500
If you think something
is wrong .......................... 506
If a warning light turns
on or a warning buzzer
sounds ............................. 507
If a warning message is
displayed ......................... 513
If you have a flat tire
(vehicles without
run-flat tires) ................... 530
If you have a flat tire
(vehicles with
run-flat tires) ................... 544
If the hybrid system will
not start ........................... 545
If the shift lever cannot
be shifted from P ............ 547
If the electronic key
does not operate
properly........................... 548
If the 12-volt battery is
discharged ....................... 550
If your vehicle overheats .. 555
If the vehicle becomes
stuck................................ 559
Page 528 of 628
5148-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
Master warning light
The master warning light also comes on or flashes in order to indicate that a
message is currently being displayed on the multi-information display.
Multi-information display
If any of the warning lights come on again after the following actions
have been performed, contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
If a warning message is displayed
If a warning is shown on the multi-information display, stay calm and
perform the following actions:
Except F SPORT modelsF SPORT models (when the main
meter is in the center position)
F SPORT models (when the
main meter is in the right-side
position)
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2
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5218-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53B95E)
Indicates that the power switch is turned off or
turned to ACCESSORY mode and the driver’s door
is opened while the lights are turned on
A buzzer also sounds.
Turn the lights off.
(If equipped)
Indicates that the moon roof is not fully closed
(with the power switch off, and the driver’s door
open)
A buzzer also sounds.
Close the moon roof.
Indicates that the windows are not fully closed
(with the power switch off, and the driver’s door
open)
A buzzer also sounds.
Close all the windows.
(If equipped)
Indicates that the windows and the moon roof are
not fully closed (with the power switch off, and the
driver’s door open)
A buzzer also sounds.
Close all the windows and the moon roof.
Indicates a malfunction in the brake override sys-
tem
A buzzer also sounds.
Have the vehicle inspected by any authorized
Lexus dealer or repairer, or another duly quali-
fied and equipped professional.
Indicates that engine oil level is low
A buzzer also sounds.
Check the level of engine oil, and add if neces-
sary.
Indicates that the hybrid system has overheated
This message may be displayed when driving
under severe operating conditions. (For example,
when driving up a long steep hill.)
A buzzer also sounds.
Stop and check. (P. 556)
Warning messageDetails/Actions
(Flashes)
(Flashes)
(Flashes)
(Flashes)
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5248-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
*1: Refer to the separate “Lexus Service Booklet” or “Lexus Warranty Booklet”
for the maintenance interval applicable to your vehicle.
*2: For the EV drive mode operating conditions: P. 214
Indicates that the EV drive mode is not available*2
The reason the EV drive mode is not available
(the vehicle is idling, hybrid battery [traction bat-
tery] charge is low, speed is higher than the EV
drive mode operating speed range, accelerator
pedal is depressed too much) may be displayed.
A buzzer also sounds.
Use the EV drive mode when it becomes avail-
able.
Indicates that the EV drive mode has been automat-
ically canceled
*2
The reason the EV drive mode is not available
(the hybrid battery [traction battery] charge is
low, speed is higher than the EV drive mode
operating speed range, accelerator pedal is
depressed too much) may be displayed.
A buzzer also sounds.
Drive the vehicle for a while.
Warning messageDetails/Actions
(Except F
SPORT mod-
els)(F SPORT
models)
(Flashes) (Flashes)
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5258-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53B95E)
Warning messages
The warning message illustrations used are intended as examples, and may differ
from the image that is actually displayed on the multi-information display.
Warning message in radar cruise mode (if equipped)
In the following situations, the warning message may not be displayed even if
vehicle-to-vehicle distance decreases:
When your vehicle and the vehicle ahead are traveling at the same speed or the
vehicle ahead is traveling more quickly than your vehicle
When the vehicle ahead is traveling at a very low speed
Immediately after cruise control speed is set
At the instant the accelerator pedal is depressed
The LDA (Lane Departure Alert) lane departure warning function (if equipped)
In the following situations, the warning message will not be displayed even if a
lane line is crossed.
When the vehicle speed deviates from the operating range of the LDA system
functions
When the lane lines cannot be recognized
After changing the engine oil (if equipped)
Make sure to reset the oil change system. (P. 442)
Warning buzzer
P. 512
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5268-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
Interior
buzzerExterior
buzzerWarning messageDetails/Actions
Con-
tinu-
ousThe 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.
Con-
tinu-
ousCon-
tinu-
ous
The 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 electronic key back
into the vehicle.
Once
The electronic key is not
detected when an attempt is
made to start the hybrid system.
Start the hybrid system with
the electronic key present.
OnceCon-
tinu-
ous
An attempt was made to exit the
vehicle with the electronic key
and lock the doors without first
turning the power switch off
when the shift lever was in P.
Turn the power switch off and
lock the doors again.
(Flashes)
(Displayed alternately)
(Flashes)
(Flashes)
(Displayed alternately)
(Flashes)
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5508-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
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.
When the electronic key is detected,
a buzzer sounds and the power
switch will turn to ON mode.
When the smart entry & start system
is deactivated in customization set-
ting, 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.
Stopping the hybrid system
Shift the shift lever to P and press the power switch as you normally do when
stopping the hybrid system.
Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immediately when the battery is depleted. (P.
472)
Alarm (if equipped)
Using the mechanical key to lock the doors will not set the alarm system.
If a door is unlocked using the mechanical key when the alarm system is set, the
alarm may be triggered.
Changing power switch modes
Release the brake pedal and press the power switch in step above.
The hybrid system does not start and modes will be changed each time the switch
is pressed. (P. 210)
When the electronic key does not work properly
Make sure that the smart entry & start system has not been deactivated in the
customization setting. If it is off, turn the function on.
(Customizable features P. 575)
Check if battery-saving mode is set. If it is set, cancel the function. (P. 150)
Starting the hybrid system
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2
3
4
3
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5568-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
The needle of the engine coolant temperature gauge (P. 110) enters
the red zone or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
“Hybrid System Overheat” is shown on the multi-information display.
Steam comes out from under the hood.
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 conditioning sys-
tem, 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.
After the hybrid system has
cooled down sufficiently,
inspect the hoses and radiator
core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact any
authorized Lexus dealer or
repairer, or another duly quali-
fied and equipped professional.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
1
2
3
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2