2021 LEXUS IS300 Owners Manual

3377-2. Steps to take in an emergency
7
When trouble arises
■Brake system warning light (warning buzzer)
■Brake system warning light (warning buzzer)
■High coolant temperature warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
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 your Lexus dealer.
Actions to the warning lights or warning buzzers
Warning lightDetails/Actions
(U.S.A.)
or
(red)
(Canada)
Indicates that:
 The brake fluid level is low; or
 The brake system is malfunctioning
 Immediately stop the vehicle in a safe place and contact your Lexus
dealer. Continuing to drive the vehicle may be dangerous.
Warning lightDetails/Actions
(yellow)
Indicates a malfunction in the parking brake system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
Indicates that the engine coolant temperature is too high
Immediately stop the vehicle in a safe place.
Handling method ( P.365)

3387-2. Steps to take in an emergency
■Charging system warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
■Low engine oil pressure warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
■Malfunction indicator lamp (warning buzzer)
■SRS warning light (warning buzzer)
Warning lightDetails/Actions
Indicates a malfunction in the vehicle’s charging system
Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
Warning lightDetails/Actions
Indicates that the engine oil pressure is too low
 Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
Warning lightDetails/Actions
(U.S.A.)
or
(Canada)
Indicates a malfunction in:
 The electronic engine control system;
 The electronic throttle control system; or
 The electronic automatic transmission control system
 Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
Warning lightDetails/Actions
Indicates a malfunction in:
 The SRS airbag system;
 The front passenger occupant classification system; or
 The seat belt pretensioner system
 Have the vehicle inspected by your Lexus dealer immediately.

3397-2. Steps to take in an emergency
7
When trouble arises
■ABS warning light (warning buzzer)
■Brake Override System warning light/Drive-Start Control warning light*
(warning buzzer)
*: This light illuminates on the multi-information display.
Warning lightDetails/Actions
(U.S.A.)
or
(Canada)
Indicates a malfunction in:
 The ABS; or
 The brake assist system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
When a buzzer sounds:
Indicates a malfunction in:
Brake Override System
 Drive-Start Control
 Have the vehicle inspected by your Lexus dealer immediately.
 Indicates that the shift position was changed and Drive-Start Control
was operated while depressing the accelerator pedal.
 Momentarily release th e accelerator pedal.
 Parking Support Brake function (for static objects) is operating (if
equipped)
 Follow the instructions displayed on the multi-information display.
When a buzzer does not sound:
Indicates that the accelerator and brake pedals are being depressed
simultaneously, and the Brake Override System is operating.
 Release the accelerator pedal and depress the brake pedal.

3407-2. Steps to take in an emergency
■Electric power steering system warning light (warning buzzer)
■Low fuel level warning light
■Driver’s and front passenger’s seat belt reminder light (warning buzzer)*
*: Driver’s seat belt warning buzzer:
The driver’s seat belt warning buzzer sounds to al ert the driver that his or her seat belt is not
fastened. Once the engine switch is turned to IGNITION ON mode, the buzzer sounds. If
the seat belt is still unfastened, the buzzer sounds intermittently for a certain period of time
after the vehicle reaches a certain speed.
Front passenger’s seat belt warning buzzer:
The front passenger’s seat belt warning buzzer sounds to alert the front passenger that his
or her seat belt is not fastened. If the seat be lt is unfastened, the buzzer sounds intermittenly
for a certain period of time after the vehicle reaches a certain speed.
■Rear passengers’ seat belt reminder lights*1 (warning buzzer)*2
Warning lightDetails/Actions
(red)
or
(yellow)
Indicates a malfunction in the EPS (Electric Power Steering) system
Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
Indicates that remaining fuel is approximately 2.6 gal. (10 L, 2.2 Imp.
gal.) or less
 Refuel the vehicle.
Warning lightDetails/Actions
Warns the driver and/or front pass enger to fasten their seat belts
 Fasten the seat belt.
If the front passenger’s seat is occupied, the front passenger’s seat
belt also needs to be fastened to make the warning light (warning
buzzer) turn off.
Warning lightDetails/Actions
Warns the rear passengers to fasten their seat belts
 Fasten the seat belt.

3417-2. Steps to take in an emergency
7
When trouble arises
*1: This light illuminates on the center panel.
*2: Rear passengers’ seat belt warning buzzer:
The rear passengers’ seat belt warning buzzer sounds to alert the rear passenger that his or
her seat belt is not fastened. If the seat belt is unfastened, the buzzer sounds intermittently
for a certain period of time, af ter the seat belt is fastened and unfastened and the vehicle
reaches a certain speed.
■Tire pressure warning light
■LTA indicator (warning buzzer)
■Intuitive parking assist OFF indicator (warning buzzer)
Warning lightDetails/Actions
When the light comes on after blinking for approximately 1 minute:
Malfunction in the tire pressure warning system
 Have the system checked by your Lexus dealer.
When the light comes on:
Low tire inflation pressure such as
 Natural causes
 Flat tire
 Immediately stop the vehicle in a safe place.
Handling method ( P.344)
Warning lightDetails/Actions
(orange)
Indicates a malfunction in th e LTA (Lane Tracing Assist)
 Follow the instructions displayed on the multi-information display.
(  P.189)
Warning lightDetails/Actions
(flashes)
(if equipped)
Indicates a malfunction in the in tuitive parking assist function
 Have the vehicle inspected by your Lexus dealer immediately.
Indicates that the system is temporarily unavailable, possibly due to a
sensor being dirty or covered with ice, etc.
 Follow the instructions displayed on the multi-information display.
(  P.212)

3427-2. Steps to take in an emergency
■RCTA OFF indicator (warning buzzer)
■PKSB OFF indicator (warning buzzer)
■PCS warning light
Warning lightDetails/Actions
(flashes)
(if equipped)
Indicates a malfunction in the RCTA (Rear Cross Traffic Alert) function
 Have the vehicle inspected by your Lexus dealer immediately.
Indicates that the rear bumper around the radar sensor is covered with
dirt, etc. ( P.204)
 Follow the instructions displayed on the multi-information display.
(  P.217)
Warning lightDetails/Actions
(flashes)
(if equipped)
When a buzzer sounds:
Indicates a malfunction in the PK SB (Parking Support Brake) system
 Have the vehicle inspected by your Lexus dealer immediately.
When a buzzer does not sound:
Indicates that the system is temporarily unavailable, possibly due to a
sensor being dirty or covered with ice, etc.
 Follow the instructions displayed on the multi-information display.
(  P.225, 346)
Warning lightDetails/Actions
(flashes or illumi-
nates)
When a buzzer sounds simultaneously:
Indicates a malfunction has occurred in the PCS (Pre-Collision System).
 Have the vehicle inspected by your Lexus dealer immediately.
When a buzzer does not sound:
The PCS (Pre-Collision System) has become temporarily unavailable,
corrective action may be necessary.
 Follow the instructions displayed on the multi-information display.
(  P.168, 347)
If the PCS (Pre-Collision System) or VSC (Vehicle Stability Control)
system is disabled, the PCS warning light will illuminate.
 P.179

3437-2. Steps to take in an emergency
7
When trouble arises
■Slip indicator
■Parking brake indicator (warning buzzer)
■Brake hold operated indicator (warning buzzer)
■Warning buzzer
In some cases, the bu zzer may not be heard
due to being in a noisy location or audio
sound.
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause th e warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■SRS warning light
This warning light system monitors the air-
bag sensor assembly, fr ont impact sensors,
side impact sensors (front door), side
impact sensors (front), side impact sensors
(rear), driver’s seat position sensor, driver’s
seat belt buckle sw itch, front passenger
occupant classificatio n system (ECU and
sensors), “AIR BAG ON” indicator light,
“AIR BAG OFF” indicator light, front pas-
senger’s seat belt buckle switch, seat belt
pretensioners and force limiters, airbags,
interconnecting wiring and power sources.
(  P.28)
■If the malfunction indicator lamp comes
on while driving
First check the following:
Warning lightDetails/Actions
Indicates a malfunction in:
 The VSC system;
 The TRAC system; or
 The hill-start assist control system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
(flashes)
(U.S.A.)
or
(flashes)
(Canada)
It is possible that the parking brake is not fully engaged or released
 Operate the parking brake switch once again.
This light comes on when the parking brake is not released. If the light
turns off after the parking brake is fu lly released, the system is operating
normally.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.

3447-2. Steps to take in an emergency
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving
trips.
If the light does not go off even after several
trips, contact your Lexus dealer as soon as
possible.
■Electric power steering system warning
light (warning buzzer)
When the battery charge becomes insuffi-
cient or the voltage temporarily drops, the
electric power steeri ng system warning
light may come on and the warning buzzer
may sound.
■When the tire pressure warning light
comes on
Inspect the tires to check if a tire is punc-
tured.
If a tire is punctured: P.349
If none of the tires are punctured:
Turn the engine switch off then turn it to
IGNITION ON mode. Check if the tire
pressure warning light comes on or blinks.
If the tire pressure wa rning light blinks for
approximately 1 minute then stays on
There may be a malfunction in the tire
pressure warning syst em. Have the vehicle
inspected by your Lexus dealer immedi-
ately.
If the tire pressure warning light comes
on
1 After the temperature of the tires has
lowered sufficiently, check the inflation
pressure of each tire and adjust them to
the specified level.
2 If the warning light does not turn off
even after several minutes have
elapsed, check that the inflation pres-
sure of each tire is at the specified level
and perform initialization. ( P.308)
■The tire pressure warning light may
come on due to natural causes
The tire pressure wa rning light may come
on due to natural causes such as natural air
leaks and tire inflation pressure changes
caused by temperature. In this case, adjust-ing the tire inflation pressure will turn off the
warning light (after a few minutes).
■When a tire is replaced with the spare
tire
The spare tire is not equipped with a tire
pressure warning valve and transmitter. If a
tire goes flat, the tire pressure warning light
will not turn off even though the flat tire has
been replaced with the spare tire.
■Conditions that the tire pressure warn-
ing system may not function properly
 P.306
WARNING
■If both the ABS and the brake system
warning lights remain on
Stop your vehicle in a safe place immedi-
ately and contact your Lexus dealer.
The vehicle will become extremely
unstable during br aking, and the ABS
system may fail, which could cause an
accident resulting in death or serious
injury.
■When the electric power steering
system warning light comes on
When the light comes on yellow, the
assist to the power st eering is restricted.
When the light comes on red, the assist
to the power steering is lost and handling
operations of the steering wheel 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 precau-
tions.
Failure to do so could cause a loss of
vehicle control and result in death or
serious injury.
●Decelerate to the lowest appropriate
speed as soon as possible. Do not
drive over 50 mph (80 km/h).