Page 417 of 573

4167-3. Do-it-yourself maintenance
IS350/250_U (OM53758U)
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.
■Situations in which the tire pressure warning system may not operate properly
●In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• Lock nuts are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the wheels or wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
• If tires not equipped with tire pressure warning valves and transmitters are used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air-
port or other facility th at generates strong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless
communication device
If tire position information is not correctl y displayed due to the radio wave conditions,
the display may be corrected by driving and changing the radio wave conditions.
●When the vehicle is parked, the time taken for the warning to start or go off could be
extended.
●When tire inflation pressure declines rapidly for example when a tire has burst, the
warning may not function.
■The initialization operation
●Make sure to carry out initialization af ter adjusting the tire inflation pressure.
Also, make sure the tires are cold before carry ing out initialization or tire inflation pres-
sure adjustment.
●If you have accidentally turned the engine swit ch off during initialization, it is not neces-
sary to press the reset switch again as init ialization will restart automatically when the
engine switch has been turned to IG NITION ON mode for the next time.
●If you accidentally press the reset switch when initialization is not necessary, adjust the
tire inflation pressure to the specified level when the tires are co ld, and conduct initial-
ization again.
Page 421 of 573
4207-3. Do-it-yourself maintenance
IS350/250_U (OM53758U)
The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
( P. 5 0 7 )
Tire inflation pressure
Tire inflation pressure
Page 446 of 573
445
When trouble arises8
IS350/250_U (OM53758U)
8-1. Essential informationEmergency flashers .................. 446
If your vehicle has to be stopped in
an emergency........................... 447
8-2. Steps to take in an emergency
If your vehicle needs to be towed ................................448
If you think something is wrong ....................................... 453
Fuel pump shut off system ...... 454
If a warning light turns on or a warning buzzer sounds ..... 455
If a warning message is displayed ..................................461
If you have a flat tire................... 475
If the engine will not start ........485
If the shift lever cannot be shifted from P ..................... 487
If the electronic key does not operate properly ............ 488
If the vehicle battery is discharged ............................. 490
If your vehicle overheats ......... 494
If the vehicle becomes stuck ..............................................497
Page 462 of 573
4618-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53758U)
Master warning light
The master warning light also comes on or flashes in order to indicate that a
message is currently being displayed 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-information display, stay calm and perform
the following actions:
Except F SPORT modelsF 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
Page 469 of 573

4688-2. Steps to take in an emergency
IS350/250_U (OM53758U)
Indicates a malfunction in the tire pressure warning sys-
tem
Stop the vehicle in a safe place and turn the engine
switch off then on again.
If the tire pressure warning indicator flashes for 1
minute then illuminates, there is a malfunction in the
system. Have the vehicle inspected at your Lexus
dealer.
Indicates that the tire position information cannot be rec-
ognized
Drive for a short while an d check if the display
updates.
If the radio wave conditions improve, the display
may return to normal. If th e tire pressure is still not
displayed after driving for several minutes, stop the
vehicle in a safe place, turn the engine switch off
then on again, and start driving.
If the tire pressure is still not displayed even after
repeating this process several times, have the vehi-
cle inspected at your Lexus dealer.
Indicates that the wash er fluid level is low
Add washer fluid.
Indicates that remaining fuel is approximately 2.6 gal.
(10 L, 2.2 Imp. gal.) or less
Refuel the vehicle.
Indicates that the TRAC (Tra ction Control) system has
been deactivated
Tu r n t h e T R A C o n . ( P. 2 3 6 )
(U.S.A. only)
Indicates that all maintenance according to the driven
distance on the maintenance schedule
* should be per-
formed soon.
Comes on approximately 4500 miles (7200 km) after
the maintenance data has been reset.
If necessary, perform maintenance.
Wa r n i n g m e s s a g eDetails/Actions
Page 471 of 573

4708-2. Steps to take in an emergency
IS350/250_U (OM53758U)
■Wa r n i n g m e s s a g e s
The warning message illustrations used are intended as examples, and may differ from
the image that is actua lly displayed on the multi-information display.
■Warning message in radar cruise mode (if equipped)
In the following situations, the warning messag e may not be displayed even if vehicle-to-
vehicle distance decreases:
●When your vehicle and the vehicle ahead are traveling at the same speed or the vehicle
ahead is traveling more quickly than your vehicle
●When the vehicle ahead is traveling at a very low speed
●Immediately after cruise control speed is set
●At the instant the accelerator pedal is depressed
■The LDA (Lane Departure Alert) lane departure warning function
In the following situations, the warning messag e will not be displayed even if a lane line is
crossed.
●When the vehicle speed deviates from the operating range of the LDA system func-
tions
●When the lane lines cannot be recognized
■Reset the maintenance data (U.S.A. only)
Make sure to reset the oil change system. ( P. 3 9 1 )
■Conditions that the tire pressure warning system may not function properly
P. 4 1 6
■Warning buzzer
P. 4 5 8
Page 472 of 573

4718-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53758U)
InteriorbuzzerExteriorbuzzerWa r n i n g m e s s a g eDetails/Actions
Con-
tinuous The driver’s door was opened when
the shift lever was not in P and the
engine switch was not turned off.
Shift the shift lever to P.
Con-
tinuousCon-
tinuous
The driver’s door was opened and
closed while the electronic key was
not in the vehicle, the shift lever was
not in P and the engine switch was
not turned off.
Shift the shift lever to P.
Bring the electronic key back
into the vehicle.
Once The electronic key is not detected
when an attempt is made to start the
engine.
Start the engine with the elec-
tronic key present.
OnceCon-
tinuous
An attempt was made to exit the
vehicle with the electronic key and
lock the doors without first turning
the engine switch off when the shift
lever was in P.
Turn the engine switch off and
lock the doors again.
Once3 times
The electronic key was carried out-
side the vehicle and a door other
than the driver’s door was opened
and closed while the engine switch
was in a mode other than off.
Bring the electronic key back
into the vehicle.
The driver’s door was opened and
closed while the electronic key was
not in the vehicle, the shift lever was
in P and the engine switch was not
turned off.
Turn the engine switch off.
Bring the electronic key back
into the vehicle.
(Flashes)
(Displayed alternately)
(Flashes)
(Flashes)
(Displayed alternately)
(Flashes)
(Flashes)
Page 490 of 573

4898-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53758U)
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Lexus emblem side of the
electronic key to the engine switch.
When the electronic key is detected, a
buzzer sounds and the engine switch
will turn to IGNITION ON mode.
When the smart access system with
push-button start is deactivated in cus-
tomization setting, the engine switch will
turn to ACCESSORY mode.
Firmly depress the brake pedal and check that is shown on the multi-
information display.
Press the engine switch.
In the event that the engine still cannot be started, contact your Lexus dealer.
■Stopping the engine
Shift the shift lever to P and press the engine switch as you normally do when stopping
the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediatel y when the battery is depleted. (P. 4 2 7 )
■Changing engine switch modes
Release the brake pedal and press the engine switch in step above.
The engine does not start and modes will be changed each time the switch is pressed.
( P. 1 6 0 )
■When the electronic key does not work properly
●Make sure that the smart access system wi th push-button start has not been deacti-
vated in the custom ization setting. If it is off, turn the function on.
(Customizable features P. 5 2 5 )
●Check if battery-saving mo de is set. If it is set, cancel the function. ( P. 115)
Starting the engine
1
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3
4
3