2015 Lexus IS250 engine

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.

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.

4738-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
Warning message and warning buzzer list
Wa r n i n g m e s s a g eDetails/Actions
(If equipped)
Indicates that:
• There is a high possibility of a frontal collision; or
• The pre-collision braking function is operatingA buzzer also sounds.
 Slow the vehicle by applying the brakes.
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.
(If equipped)
Indicates that your vehicle is nearing the vehicle ahead
(in vehicle-to-vehicle distance mode)
A buzzer also sounds.
 Slow the vehicle by applying the brakes.
(If equipped)
Alerts the driver that the vehicle has deviated from the
lane (while the LDA [Lane Departure Alert] system is
operating)
The lane line on the side the vehicle has deviated from
flashes in yellow.
The warning buzzer sounds continuously.
 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.
(Flashes)
(Flashes)
(Flashes)
(U.S.A.) (Canada)

4758-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
Indicates that the vehicle is being driven at 3 mph (5 km/
h) or more with the parking brake still engaged. A buzzer also sounds.
 Release the parking brake.
Indicates that the shift lever was used to attempt to shift
to the first gear position in M mode on a slippery road
surface
The gear position will not sh ift from the second gear.
A buzzer also sounds.
 Drive the vehicle in the second or a higher gear
position.
Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system
A 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. 5 0 6
(If equipped)
Indicates that the radar sensor is dirty or covered with
ice
A buzzer also sounds.
 Clean the sensor.
(If equipped)
Indicates that the dynamic radar cruise control system is
unable to judge vehicle-to-vehicle distance
A buzzer also sounds.
 Tu r n o f f s n o w m o d e .
If the windshield wipers are on, turn them off or set
them to a mode other than AUTO or high speed
wiper operation.
Wa r n i n g m e s s a g eDetails/Actions
(U.S.A.) (Canada) (Flashes)
(U.S.A.) (Canada)

4768-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
(If equipped)
Indicates that the LDA (Lane Departure Alert) system is
suspended (The camera sensor temperature is higher
than the operation temperature range)
A buzzer also sounds.
 Restart the LDA after driving for a while.
(If equipped)
Indicates that a Blind Spot Monitor sensor or the sur-
rounding area on the bumper is dirty or covered with ice
A buzzer also sounds.
 Clean the sensor and its surrounding area on the
bumper.
Indicates a malfunction in:
• The cruise control system; or
• The dynamic radar cruise control system (if equipped)
Press the “ON/OFF” button once to deactivate the
system, and then press the button again to reactivate
the system.
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
(If equipped)
Indicates a malfunction in the LDA (Lane Departure
Alert) system
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
(If equipped)
Indicates a malfunction in the PCS (Pre-Collision Sys-
tem)
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
(If equipped)
Indicates a malfunction in the BSM (Blind Spot Monitor)
system
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
Indicates abnormal engine oil pressure
A buzzer also sounds.
 Immediately stop the vehicle in a safe place and
contact your Lexus dealer.
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)

4778-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
Indicates that the automatic transmission fluid tempera-
ture is too highA buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
(AWD models)
Indicates a malfunctio n in the AWD system
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
(If equipped)
Indicates a malfunction in the VGRS (Variable Gear
Ratio Steering) system
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
Indicates that the engine was stopped while driving
A buzzer also sounds.
 Operate the steering wheel with more force than
usual.
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 on
A 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.
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)
(Flashes)
(Flashes)

4788-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
(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.
Indicates a malfunction in the brake override system
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
Indicates that engine oil level is low
A buzzer also sounds.
 Check the level of engine oil, and add if necessary.
Indicates a malfunction in:
• The automatic headlig ht leveling system; or
• The Automatic High Beam system (if equipped)
• The LED headlight system (if equipped)
A buzzer also sounds.
 Have the vehicle inspected by your Lexus dealer.
Indicates that the accelerator and brake pedal are being
depressed simultaneously
Release the accelerator or brake pedal.
Indicates that the tire in flation pressure is low
 Check the tire inflation pressure, and adjust to the
appropriate level.
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)
(Flashes)