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)
1
2
Page 535 of 628

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)
Page 536 of 628

5228-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
Indicates a malfunction in:
• The automatic headlight leveling system; or
• The Automatic High Beam system (if equipped)
• The LED headlight system (if equipped)
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 the accelerator and brake pedal are
being depressed simultaneously
Release the accelerator or brake pedal.
Indicates that the cooling performance of the hybrid
battery (traction battery) has dropped
Have the vehicle inspected by any authorized
Lexus dealer or repairer, or another duly quali-
fied and equipped professional.
Indicates that the washer fluid level is low
Add washer fluid.
Indicates that remaining fuel is approximately 10 L
(2.6 gal., 2.2 Imp. gal.) or less
Refuel the vehicle.
Indicates that the TRC (Traction Control) system
has been deactivated
Turn the TRC on. (P. 295)
(If equipped)
Indicates that all maintenance is required to corre-
spond to the driven distance on the maintenance
schedule
*1.
Comes on approximately 10000 km (6214 miles)
after the maintenance data has been reset.
(The indicator will not work properly unless the
maintenance data has been reset.)
Perform the necessary maintenance. Please reset
the maintenance data after the maintenance is
performed (P. 442)
Warning messageDetails/Actions
(Flashes)
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5238-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53B95E)
(If equipped)
Indicates that the Automatic High Beam switch is
pressed while the headlights are in low beam.
Turn the high beam on and press the Automatic
High Beam switch again.
(If equipped)
Indicates that, since the VSC (Vehicle Stability
Control) system was turned off, the pre-crash brake
system operation is stopped
Turn the VSC on. (P. 295)
(If equipped)
Indicates that the PCS (Pre-Crash Safety system) is
not currently functional because the grille cover or
the sensor is dirty
Check the grille cover and the sensor and clean
them if they are dirty.
Indicates that operation of large electricity consum-
ing systems such as the air conditioning system are
suspended
Stop using unnecessary electric components to
reduce electricity consumption. Wait a while
until the electric power supply is restored.
(If equipped)
Indicates that the LDA (Lane Departure Alert) sys-
tem cannot be used because the vehicle speed is
lower than approximately 50 km/h (32 mph)
Drive the vehicle at 50 km/h (32 mph) or higher.
Warning messageDetails/Actions
(Flashes)
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5298-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53B95E)
Indicates that:
• With the power switch off, the
doors were unlocked and then
the driver’s door was opened
and closed;
• The power switch was turned
to ACCESSORY mode with-
out starting the hybrid system;
or
• The shift lever was shifted to P
from another position with the
power switch in ON mode.
Press the power switch while
depressing the brake pedal.
Once
The power switch has been
turned off with the shift lever in a
position other than P.
Shift the shift lever to P.
Once
After the power switch has been
turned off with the shift lever in a
position other than P, the shift
lever has been shifted to P.
Turn the power switch off.
Power was turned off due to the
automatic power off function.
Next time when starting the
hybrid system, increase the
engine speed slightly and
maintain that level for approx-
imately 5 minutes to recharge
the 12-volt battery.
Con-
tinu-
ous
Indicates that the hybrid system
was stopped in an emergency
while driving
To restart the hybrid system,
shift the shift lever to N and
turn the power switch to ON
mode.
*
Interior
buzzerExterior
buzzerWarning messageDetails/Actions
(Flashes)
(Flashes)
(Flashes)
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5458-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53B95E)
Run-flat tires (A “RFT” or “DSST” mark is molded on the sidewall)
Take your vehicle to the nearest
Lexus dealer or authorized tire
dealer as soon as possible if any
tire goes flat.
The vehicle can be driven for a
maximum of 300 km (186 miles)
at a speed below 60 km/h (37
mph) after the tire pressure warn-
ing light comes on. (P. 510)
In some conditions (such as at high temperatures)
You cannot continue driving for up to 300 km (186 miles).
For the detailed information on run-flat tires
See the tire warranty booklet.
If you have a flat tire (vehicles with run-flat tires)
You can continue driving a vehicle with run-flat tires even if any tire
goes flat.In this case, slow down and drive with extra caution.
NOTICE
When replacing the tires
When removing or fitting the wheels, tires or the tire pressure warning valve
and transmitter, contact any authorized Lexus dealer or repairer, or another
duly qualified and equipped professional as the tire pressure warning valve and
transmitter may be damaged if not handled correctly.
When driving over bumps
If a vehicle has a flat tire, the vehicle height will be lower than usual. Ensure
that nothing strikes the bottom of the vehicle.
To avoid damage to the tire pressure warning valves and transmitters
When a tire is repaired with liquid sealants, the tire pressure warning valve and
transmitter may not operate properly. If a liquid sealant is used, contact any
authorized Lexus dealer or repairer, or another duly qualified and equipped
professional or other qualified service shop as soon as possible. Make sure to
replace the tire pressure warning valve and transmitter when replacing the tire.
(P. 451)
Page 560 of 628

5468-2. Steps to take in an emergency
IS300h_EE(OM53B95E)
One of the following may be the cause of the problem:
The electronic key may not be functioning properly. (P. 550)
There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
There may be a malfunction in the immobilizer system. (P. 9 0 )
There may be a malfunction in the steering lock system.
The hybrid system may be malfunctioning due to an electrical problem
such as electronic key battery depletion or a blown fuse. However,
depending on the type of malfunction, an interim measure is available
to start the hybrid system. (P. 547)
One of the following may be the cause of the problem:
The 12-volt battery terminal connections may be loose or corroded.
The 12-volt battery may be discharged. (P. 551)
If the hybrid system will not start
Reasons for the hybrid system not starting vary depending on the situa-
tion. Check the following and perform the appropriate procedure:
The hybrid system will not start even though the correct starting
procedure is being followed. (P. 209)
The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume.
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5478-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53B95E)
One of the following may be the cause of the problem:
One or both of the 12-volt battery terminals may be disconnected.
The 12-volt battery may be discharged. (P. 551)
Contact any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional if the problem cannot be repaired, or if repair proce-
dures are unknown.
When the hybrid system does not start, the following steps can be used as
an interim measure to start the hybrid system if the power switch is func-
tioning normally:
Set the parking brake.
Shift the shift lever to P.
Turn the power switch to ACCESSORY mode.
Press and hold the power switch for about 15 seconds while depressing
the brake pedal firmly.
Even if the hybrid system can be started using the above steps, the system
may be malfunctioning. Have the vehicle inspected by any authorized
Lexus dealer or repairer, or another duly qualified and equipped profes-
sional.
The interior lights and headlights do not turn on, or the horn does
not sound.
Emergency start function
1
2
3
4