warning light Lexus IS350 2019 / 2019 IS300,IS350 (OM53E71U) Repair Manual

5258-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
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, but then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspecte d by your Lexus dealer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
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 your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
(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 your
Lexus dealer.
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The electronic engine control system;
• The electronic throttle control system; or
• The electronic automatic transmission control system
 Have the vehicle inspected by your Lexus dealer immediately.
SRS warning light
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.
(U.S.A.)
(Canada)
ABS warning light Indicates a malfunction in:
• The ABS; or
• The brake assist system
 Have the vehicle inspected by your Lexus dealer immediately.

5268-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
(U.S.A.)
(Canada)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 your Lexus dealer immediately.
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 displa yed on the multi-information
display. ( P. 532)
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.
(Flashes or illuminates)
PCS warning light
Indicates a malfunction in the PCS (Pre-Collision System) or that
the system is temporarily unavailable due to the vehicle being
extremely hot/cold, or dirt around a front sensor, etc.
( P. 239, 542)
 Follow the instructions displayed on the multi-information dis-
play. ( P. 239, 542)
If the PCS (Pre-Collision System ) or VSC (Vehicle Stability Con-
trol) system is disabled, the PC S warning light will illuminate.
 P. 239
Slip indicator
Indicates a malfunction in:
• The VSC (Vehicle Stability Control) system;
• The TRAC (Traction Control) system; or
• The hill-start assist control system
The light will flash when the VSC or the TRAC system is operating.
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightWarning light/Details/Actions

5278-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
(Flashes)
(If equipped)
“AFS OFF” indicator
Indicates a malfunction in the adaptive front-lighting system
 Have the vehicle inspected by your Lexus dealer immediately.
Open door warning light (warning buzzer)*2
Indicates that a door or the trunk is not fully closed
 Check that all the doors and the trunk are closed.
Low fuel level warning light
Indicates that remaining fuel is approximately 2.6 gal. (10 L, 2.2
Imp. gal.) or less
 Refuel the vehicle.
Driver’s and front passenger’s seat belt reminder light (warning
buzzer)
*3
Warns the driver and/or front passenger 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.
Rear passengers’ seat belt re minder 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 warnin g system has detected a malfunc-
tion.
 P. 532
Tire pressure warning light
When the light comes on:
Low tire inflation pressure such as
• Natural causes ( P. 529)
•Flat tire ( P. 559)
 Adjust the tire inflation pres sure 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 inflation pressure is adjusted, have the
system checked by your Lexus dealer.
When the light comes on af ter blinking for 1 minute:
Malfunction in the tire pressure warning system
 Have the system checked by your Lexus dealer.
Warning lightWarning light/Details/Actions

5288-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
*1: Parking brake engaged warning buzzer: P. 536
*2: Open door warning buzzer:
 P. 534
*3: Driver’s seat belt buzzer:
The driver’s seat belt buzzer sounds to alert the driver that his or her seat belt is not
fastened. Once the engine switch is turned to IGNITION ON mode, the buzzer
sounds for 6 seconds. If the vehicle reaches a speed of 12 mph (20 km/h), the buzzer
sounds once. If the seat belt is still unfast ened after 24 seconds, the buzzer will sound
intermittently for 6 seconds. Then, if the se at belt is still unfastened, the buzzer will
sound in a different tone for 90 more seconds.
Front passenger’s seat belt buzzer:
The front passenger’s seat belt buzzer soun ds to alert the front passenger that his or
her seat belt is not fastened. The buzzer so unds once if the vehicle reaches a speed of
12 mph (20 km/h). If the seat belt is still unfastened after 24 se conds, the buzzer will
sound intermittently for 6 seconds. Then, if the seat belt is still unfastened, the buzzer
will sound in a different to ne for 90 more seconds.
Rear passenger’s seat belt buzzer:
The rear passenger’s seat belt buzzer sounds to alert the rear passenger that his or
her seat belt is not fastened. The buzzer so unds once if the vehicle reaches a speed of
12 mph (20 km/h). If the seat belt is still unfastened after 24 se conds, the buzzer will
sound intermittently for 6 seconds. Then, if the seat belt is still unfastened, the buzzer
will sound in a different tone for 24 more seconds.
■SRS warning light
This warning light system monitors the airbag sensor assembly, front impact sensors, side
impact sensors (front door), side impact se nsors (front), side impact sensors (rear),
driver’s seat position sensor, driver’s seat belt buckle switch, front passenger occupant
classification system, “AIR BAG ON” indicat or light, “AIR BAG OFF” indicator light,
front passenger’s seat belt buckle switch, seat belt pretensioner assemblies, airbags,
interconnecting wiring and power sources. (P. 37)
■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 passenger
is not sitting in the seat.
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fu el 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 severa l trips, contact your Lexus dealer as soon as
possible.

5298-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
■Electric power steering system warning light (warning buzzer)
When the battery charge becomes insufficien t or the voltage temporarily drops, the
electric power steering system warning li ght may come on and the warning buzzer may
sound.
■When the tire pressure warning light comes on
Check the tire inflation pressu re and adjust to the appropriate level. Pushing the tire
pressure warning reset switch will not tu rn off the tire pressure warning light.
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural air
leaks and tire inflation pressure changes caus ed by temperature. In this case, adjusting
the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with the spare tire
The compact spare tire is not equipped with a tire pressure warning valve and transmit-
ter. 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 wa rning system may not function properly
 P. 490
■If the tire pressure warning light freque ntly comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute when the
engine switch is turned to IGNITION ON mo de, have it checked by your Lexus dealer.
■Warning buzzer
In some cases, the buzzer may not be heard due to being in a noisy location or audio
sound.
WARNING
■If both the ABS and the brake sy stem warning lights remain on
Stop your vehicle in a safe place immediat ely and contact your Lexus dealer. The vehi-
cle will become extremely unstable during br aking, and the ABS system may fail, which
could cause an accident resultin g in death 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.
●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 have a flat tire . Check the tires. If a tire is flat, change it
with the spare tire and have the flat tire repaired by the nearest Lexus dealer.
●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 system may not activate immediately.

5308-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
WARNING
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold and
inflated to the inflation pressure recomm ended by the vehicle manufacturer on the
vehicle placard or tire inflation pressure label (tire and load information label). (If your
vehicle has tires of a different size than the size indicated on the vehicle placard or tire
inflation pressure label [tire and load in formation label], you should determine the
proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle ha s been equipped with a tire pressure moni-
toring system (TPMS-tire pressure warning system) that illuminates a low tire pressure
telltale (tire pressure warning light) when on e or more of your tires is significantly
under-inflated. Accordingly, when the low ti re pressure telltale (tire pressure warning
light) illuminates, you should stop and check your tires as soon as possible, and inflate
them to the proper pressure. Driving on a si gnificantly under-inflated tire causes the
tire to overheat and can lead to tire failure . Under-inflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle’s handling and stopping ability.
Please note that the TPMS (tire pressure wa rning system) is not a substitute for proper
tire maintenance, and it is th e driver’s responsibility to ma intain correct tire pressure,
even if under-inflation has not reached the le vel to trigger illumination of the TPMS low
tire pressure telltale (tir e pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warning system) mal-
function indicator to indicate when the system is not operating properly. The TPMS
(tire pressure warning system) malfunction indi cator is combined with the low tire pres-
sure telltale (tire pressure warning light). When the system detects a malfunction, the
telltale will flash for approximately one mi nute and then remain continuously illumi-
nated. This sequence will cont inue upon subsequent vehicle start-ups as long as the
malfunction exists. When the malfunction in dicator is illuminated, the system may not
be able to detect or signal low tire pressure as intended.
TPMS (tire pressure warning system) malfun ctions may occur for a variety of reasons,
including the installation of replacement or alternate tires or wheels on the vehicle that
prevent the TPMS (tire pressure warning system) from functioning properly. Always
check the TPMS (tire pressure warning system) malfunction telltale after replacing one
or more tires or wheels on your vehicle to ensure that the replacement or alternate
tires and wheels allow the TPMS (tire pressu re warning system) to continue to function
properly.

5328-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
Master warning light
The master warning light also comes on or flashes in order to indicate that a
message is currently being displaye d 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 your Lexus dealer.
If a warning message is displayed
If a warning is shown on the multi-info rmation display, stay calm and perform
the following actions:
Except F SPORT modelsF 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

5458-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
Indicates that the engine switch is turned off or turned to
ACCESSORY mode and the driver’s door is opened
while the lights are turned onA buzzer also sounds.
 Turn the lights off.
(If equipped)
Indicates that the moon roof is not fully closed (with the
engine 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
engine 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 engine switch off, and the driver’s
door open)
A buzzer also sounds.
 Close all the windows and the moon roof.
Warning messageDetails/Actions
(Flashes)
(Flashes)
(Flashes)
(Flashes)

5478-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
Indicates a malfunction in:
• The automatic headlight leveling system; or
• The AFS (Adaptive Front-lighting System) (if equipped); or
• The Automatic High Beam system; or
• The LED headlight system
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
Indicates that the accelerato r and brake pedal are being
depressed simultaneously, and the Brake Override Sys-
tem is operating.
 Release the accelerator pedal and depress the
brake pedal.
Indicates that the tire in flation pressure is low
 Check the tire inflation pressure, and adjust to the
appropriate level.
Warning messageDetails/Actions
(Flashes)

5508-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
Indicates that all maintenance is required to correspond
to the driven distance on the maintenance schedule*.
 Comes on approximately 5000 miles (8000 km)
after the message has been reset. (The indicator will
not work properly unless the message has been
reset.)
Perform the necessary maintenance. Please reset
the message after the maintenance is performed.
( P. 462)
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.
Indicates that, since the VSC (Vehicle Stability Control)
system was turned off, the pre-collision braking and pre-
collision brake assist are stopped (The pre-collision
warning function will be operational)
 Turn the VSC on. ( P. 303)
Indicates that the PCS (Pre -Collision System) is tempo-
rarily unavailable
 When conditions improve, the system resumes
operation. If this message is displayed continuously,
have the vehicle inspected by your Lexus dealer.
Warning messageDetails/Actions