
5758-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
If a warning light turns on or a warning buzzer
sounds
Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, bu t then goes off, this does not necessar-
ily indicate a malfunction in the system . However, if this continues to occur,
have the vehicle inspected by any au thorized Lexus retailer or Lexus autho-
rized repairer, or any reliable repairer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
Brake system warning light Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning Immediately stop the vehicle in a safe place and contact any
authorized Lexus retailer or Lexus authorized repairer, or any
reliable repairer. Continuing to drive the vehicle may be dan- gerous.
Brake system warning light
Indicates a malfunction in:
• The regenerative braking system; or
• The electronically controlled brake system Have the vehicle inspected by any authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer immediately.
(If equipped)
Charging system warning light
Indicates a malfunction in the vehicle’s charging system Immediately stop the vehicle in a safe place and contact any
authorized Lexus retailer or Lexus authorized repairer, or any
reliable repairer.
Malfunction indicator lamp Indicates a malfunction in:
• The hybrid system;
• The emission control system (if equipped); • The electronic engine control system; or
• The electronic throttle control system
Have the vehicle inspected by any authorized Lexus retailer or Lexus authorized repairer, or any reliable repairer immediately.

5768-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
SRS warning light Indicates a malfunction in:
• The SRS airbag system; or
• The seat belt pretensioner system Have the vehicle inspected by any authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer immediately.
ABS warning light
Indicates a malfunction in: • The ABS; or
• The brake assist system
Have the vehicle inspected by any authorized Lexus retailer or Lexus authorized repairer, or any reliable repairer immediately.
Parking brake warning light (warning buzzer)*1
Indicates that the parking brake is engaged
Release the parking brake.
Electric power steering system warning light (warning buzzer) Indicates a malfunction in the EPS (Electric Power Steering) sys-
tem
Have the vehicle inspected by any authorized Lexus retailer or Lexus authorized repairer, or any reliable repairer immediately.
(If equipped)
LDA (Lane Departure Alert) indicator
If the LDA indicato r is illuminated:
Indicates a malfunction in the LDA (Lane Departure Alert with
steering control) system. Check the warning message displayed on the multi-information
display. ( P. 581)
If the LDA indicator flashes:
Indicates that the vehicle has deviated from the lane (while the
LDA [Lane Departure Alert with stee ring control] system is oper- ating)
Check the area around the vehicle and return the vehicle to
between the lane lines.
Warning lightWarning light/Details/Actions

5788-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
*1: Parking brake engaged warning buzzer:
P. 587
*2: Open door warning buzzer:
P. 583
*3: Seat belt warning buzzer:
The seat belt warning buzzer sounds to al ert the driver, front passenger and rear pas-
sengers that his or her seat belt is not fastened. The buzzer sounds for 30 seconds
after the vehicle reaches a speed of 20 km/h (12 mph). Then, if the seat belt is still unfastened, the buzzer w ill sound in a different tone for 90 more seconds.
■Front passenger detection sensor, seat belt reminder and warning buzzer
●If luggage is placed on the front passenger seat, the front passenger detection sensor
may cause the warning light to flash and the warning buzzer to sound even if a passen-
ger is not sitting in the seat.
●If a cushion is placed on the seat, the sens or may not detect a passenger, and the warn-
ing light may not operate properly.
■If the malfunction indicator lamp comes on while driving
The malfunction indicato r lamp will come on if the fuel tank becomes completely empty.
If the fuel tank is empty, refuel the vehi cle immediately. The malfunction indicator lamp
will go off after several trips.
If the malfunction indicator lamp does not go off, contact any authorized Lexus retailer or
Lexus authorized repairer, or any re liable repairer as soon as possible.
Rear passengers’ seat belt reminder lights (warning buzzer)*3
Warns the rear passengers to fasten their seat belts
Fasten the seat belt.
Master warning light
A buzzer sounds and the warning light comes on and flashes to indicate that the master warning system has detected a malfunc-
tion.
P. 581
Tire pressure warning light When the light comes on:
Low tire inflation pressure such as
• Natural causes ( P. 579) •Flat tire ( P. 610, 625)
Adjust the tire inflation pressure to the specified level.
The light will turn off after a few minutes. In case the light does not turn off even if the tire inflat ion pressure is adjusted, have the
system checked by any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer. When the light comes on after blinking for 1 minute:
Malfunction in the tire pressure warning system
Have the system checked by any authorized Lexus retailer or Lexus authorized repairer, or any reliable repairer.
Warning lightWarning light/Details/Actions

5808-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
WARNING
■If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact any authorized Lexus retailer
or Lexus authorized repairer, or any re liable repairer. The vehicle will become
extremely unstable during braking, and the ABS system may fail, which could cause an accident resulting in de ath or serious injury.
■When the electric power steering system warning light comes on
The steering wheel may become extremely heavy. When steering wheel operations are heavier than usual, grip the steering wheel firmly
and operate it using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precaution s. Failure to do so could cause a loss of
vehicle control and result in death or serious injury.
Vehicles with an emergency tire puncture repair kit
●Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pressure
immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust- ment, it is probable that you ha ve a flat tire. Check the tires. If a tire is flat, repair the
flat tire by using emergency tire puncture repair kit.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could lose control of the steering wheel or the brakes.
Vehicles with run-flat tires
●Decelerate to the lowest appropriate speed as soon as possible. Do not drive over 60 km/h (37 mph).
●Check and adjust the tire inflation pressure immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust- ment, it is probable that you have a flat tire. Have the tire replaced by the nearest
authorized Lexus retailer or Lexus author ized repairer, or any reliable repairer.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning syst em may not activate immediately.
NOTICE
■To ensure the tire pressure warning system operates properly
Do not install tires with different specifications or makers, as the tire pressure warning system may not operate properly.

5828-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
Warning message and warning buzzer list
Warning messageDetails/Actions
(If equipped)
Indicates that there is a high possibility of a frontal colli-
sion, or that the pre-collision braking function is operat- ing
A buzzer also sounds.
Avoid the collision by decelerating using the brakes or taking other evasive actions.
Indicates that the hybrid sy stem was stopped with the
shift lever not in P
A buzzer also sounds. Shift the shift lever to P.
Indicates that the hybrid system was stopped while driv-
ing
A buzzer also sounds. Stop the vehicle in a safe place such as the shoulder
of a road.
(If equipped)
Indicates that your vehicle is nearing the vehicle ahead
(in vehicle-to-vehicle distance control mode) A buzzer also sounds.
Slow the vehicle by applying the brakes.
(Flashes)
(Flashes)

5838-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
(If equipped)
Indicates that the vehicle has deviated from the lane (while the LDA [Lane Departure Alert with steering con-
trol] system are operating)
The lane line on the side the vehicle has deviated from flashes in amber.
A buzzer also sounds.
Check around the vehicle and back to inside of the lane lines.
Indicates that:• The brake fluid level is low; or
• The brake system is malfunctioning
A buzzer also sounds. Immediately stop the vehicle in a safe place and
contact any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer. Con- tinuing to drive the vehicle may be dangerous.
Indicates a malfunction in the hybrid system
A buzzer also sounds.
Immediately stop the vehicle in a safe place and contact any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
Indicates that one or more of the doors is not fully closed The system also indicates which doors are not fully
closed.
If the vehicle reaches a speed of 5 km/h (3 mph),
flashes and a buzzer sounds to indicate that
the door(s) are not yet fully closed. Make sure that all the doors are closed.
Warning messageDetails/Actions
(Flashes)
(Flashes)

5858-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
Indicates that the accelerator pedal is depressed to stop the vehicle on an upward slope, etc.
A buzzer also sounds.
Release the accelerator pedal and depress the brake pedal.
Indicates that the hybrid battery (traction battery) powerhas dropped because a long period of time has elapsed
after shifting the shift lever to N
A buzzer also sounds. Restart the hybrid system when starting the vehicle.
Indicates a malfunction in the hybrid system
A buzzer also sounds.
Immediately stop the vehicle in a safe place and contact any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
Warning messageDetails/Actions
(Flashes)
(Flashes)

5878-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
Indicates that the vehicle is being driven at 5 km/h (3
mph) or more with the parking brake still engaged A buzzer also sounds.
Release the parking brake.
Indicates that the shift position was changed and drive
start control was operated wh ile depressing the acceler-
ator pedal A buzzer also sounds.
Momentarily release the accelerator pedal.
(If equipped)
Indicates that the LDA (Lane Departure Alert with steer-
ing control) system has dete rmined that the driver does
not have their hands on the steering wheel while the steering control function is on
A buzzer also sounds. (For Israel)
Firmly hold the steering wheel.
(If equipped)
Indicates that steering control function is temporarily canceled due to the LDA (Lane Departure Alert with
steering control) system determining that the driver
does not have their hands on the steering wheel while the steering control function is on
Firmly hold the steering wheel.
Warning messageDetails/Actions
(Flashes)
(Flashes)