brake Lexus IS300 2020 / LEXUS 2020 IS300,IS350 (OM53F29U) Repair Manual

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

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. If the seat belt is still unfastened, the buzzer sounds intermittently for a certain
period of time after the ve hicle 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 belt is unfastened, the buzzer sounds
intermittently for a certain period of time after the vehicle reaches a certain speed.
Rear passenger’s 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 pe riod of time, after the seat belt is fastened and unfas-
tened and the vehicle reaches a certain speed.
■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 turn off the tire pressure warning light.
■The tire pressure warning light ma y 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 system 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 braking, 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.

5338-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
Warning message and warning buzzer list
Warning messageDetails/Actions
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 engine was stopped with the shift lever
not in P
A buzzer also sounds.
 Shift the shift lever to P.
Indicates that the engine was stopped while driving
A buzzer also sounds.
 Stop the vehicle in a safe place such as the shoulder
of a road.
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)

5348-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
Indicates that the vehicle has deviated from the lane
(while the LDA [Lane Departure Alert with steering con-
trol] system is 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 your Lexus dealer. Continuing to drive the
vehicle may be dangerous.
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 3 mph (5 km/h),
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)
(U.S.A.) (Canada) (Flashes)

5368-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
Indicates a malfunction in the EPS (Electric Power Steer-
ing) system
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
Indicates that the vehicle is being driven at 3 mph (5
km/h) or more with the pa rking brake still engaged.
A buzzer also sounds.
 Release the parking brake.
Warning messageDetails/Actions
(U.S.A.) (Canada) (Flashes)

5398-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner systemA buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
Indicates a malfunction in:
• The ABS; or
• The brake assist system
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
Indicates that the engine coolant temperature is too high
A buzzer also sounds.
 P. 579
Warning messageDetails/Actions
(U.S.A.) (Canada)

5468-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
Indicates a malfunction in the Drive-Start Control
A buzzer also sounds.
 Have the vehicle inspecte d by your Lexus dealer
immediately.
Indicates a malfunction in the Brake Override System A buzzer also sounds.
 Have the vehicle inspecte d by your Lexus dealer
immediately.
Indicates that engine oil level is low
This message may ap pear if the vehicle is stopped on a
slope. Move the vehicle to a level surface and check to
see if the message disappears.
 Check the level of engine oil, and add if necessary.
Warning messageDetails/Actions

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