2015 Lexus IS250 warning light

4307-3. Do-it-yourself maintenance
IS350/250_U (OM53C50U)
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drivetrain as well as dangerous han-
dling characteristics, which may lead to an accident resulting in death or serious injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
●Do not tow if your vehicle has a compact spare tire installed.
■When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first adjusting the tire
inflation pressure to the specified level. Otherwise, the tire pressure warning light may
not come on even if the tire inflation pressu re is low, or it may come on when the tire
inflation pressure is actually normal.
■Caution regarding interference with electronic devices
●Users of any electrical medical device other than implantable cardiac pacemakers,
cardiac resynchronization therapy-pacemakers or implantable cardioverter defibril-
lators should consult the ma nufacturer of the device for information about its opera-
tion under the influence of radio waves.
Radio waves could have unexpected effe cts on the operation of such medical
devices.
●People with implantable cardiac pacemakers,
cardiac resynchronization therapy-pacemak-
ers or implantable cardioverter defibrillators
should not come within 17.7 in. (450 mm) of
the tire pressure warning system initiators.
The radio waves may affect the operation of
such devices.

455
When trouble arises8
IS350/250_U (OM53C50U)
8-1. Essential informationEmergency flashers .................. 456
If your vehicle has to be stopped in an
emergency................................. 457
8-2. Steps to take in an emergency
If your vehicle needs to be towed ........................................... 458
If you think something is wrong ........................................... 464
Fuel pump shut off system ...... 465
If a warning light turns on or a warning buzzer
sounds.......................................... 466
If a warning message is displayed......................................472
If you have a flat tire...................486
If the engine will not start ........ 496
If the shift lever cannot be shifted from P............................ 498
If the electronic key does not operate properly ............. 499
If the vehicle battery is discharged .................................502
If your vehicle overheats .........506
If the vehicle becomes stuck .............................................509

4668-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
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 inspected by your Lexus dealer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
Brake system warning light (warning buzzer)*1
Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning This light also comes on when the parking brake is not released.
If the light turns off after the pa rking brake is fully released the
system is operating normally.
 Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
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.

4678-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
Electric power steering system warning lightIndicates a malfunction in the EP S (Electric Power Steering) sys-
tem
 Have the vehicle inspected by your Lexus dealer immediately.
(Flashes)
(If equipped)
Pre-collision system warning light Indicates a malfunction in the PCS (Pre-Collision System)
The warning light will operate as follows, even when the system is
not malfunctioning:
• The light will flash quickly when the system is operating.
( P. 2 4 6 )
• The light will turn on when the pre-collision system is disabled.
(  P. 2 4 7 )
• The light will turn on when th e VSC (Vehicle Stability Control)
system is disabled. ( P. 2 4 2 )
• The light will flash when the system cannot temporarily be used.
( P. 4 8 0 )
 Have the vehicle inspected by your Lexus dealer immediately.
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.
Automatic headlight leveling system warning light
Indicates a malfunction in the au tomatic headlight leveling 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.
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 fa stened to make the warning light
(warning buzzer) turn off.
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. 4 7 2
Warning lightWarning light/Details/Actions

4688-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
*1: Parking brake engaged warning buzzer: P. 4 7 5
*2: Open door warning buzzer:
 P. 4 74
*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 10 seconds. Then, if the seat belt is still unfastened, the buzzer will
sound in a different tone for 20 more seconds.
Front passenger’s seat belt buzzer:
The front passenger’s seat belt buzzer sounds to alert the front passenger that his or
her seat belt is not fastened. The buzzer sounds once if the vehicle reaches a speed of
12 mph (20 km/h). If the seat belt is still unfastened after 24 seconds, the buzzer will
sound intermittently for 10 seconds. Then, if the seat belt is still unfastened, the buzzer
will sound in a different tone for 20 more seconds.
Tire pressure warning light When the light comes on:
Low tire inflation pressure such as
• Natural causes ( P. 4 6 9 )
•Flat tire ( P. 4 8 6 )
 Adjust the tire inflation pressure to the specified level.
The light will turn off after a fe w 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 after blinking for 1 minute:
Malfunction in the tire pressure warning system
 Have the system checked by your Lexus dealer.
Warning lightWarning light/Details/Actions

4698-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
■SRS warning light
This warning light system monitors the airbag sensor assembly, front 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 switch, front passenger occupant
classification system, “AIR BAG ON” indica tor light, “AIR BAG OFF” indicator light,
front passenger’s seat belt buckle switch, seat belt pretensioner assemblies, airbags,
interconnecting wiring and power sources. ( P. 3 8 )
■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 wa rning 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 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 severa l trips, contact your Lexus dealer as soon as
possible.
■Electric power steering system warning light (warning buzzer)
When the battery charge becomes insufficie nt of the voltage temporarily drops, the
electric power steering system warning light may come on and the warning buzzer may
sound.
■When the tire pressure warning light comes on
Check the tire inflation pressure 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 caused 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 warning system may not function properly
P. 4 2 8
■If the tire pressure warning light frequently 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.

4708-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
CAUTION
■If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately 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 resulting in death or serious injury.
■When the electric power steering system warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than us ual when operating, hold firmly and oper-
ate using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precautions. 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.

4718-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
CAUTION
■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 la bel (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 has 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 significantly 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 ma y 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 the driver’s resp onsibility to maintain correct tire pressure,
even if under-inflation has no t reached the level to trigger illumination of the TPMS low
tire pressure telltale (tire 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 minu te 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 indicator 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 syst em) 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 pressure warning system) to continue to function
properly.
NOTICE
■To ensure the tire pressure warning system operates properly
Do not install tires with different specificatio ns or makers, as the tire pressure warning
system may not operate properly.