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422
4-3. Do-it-yourself maintenance
IS350/250_U
CAUTION
■Tire pressure warning system operation
The tire pressure warning system may not provide warning immediately if a tire
bursts or if sudden air leakage occurs.
■When inspecting or replacing tires
Observe the following precautions to prevent accidents. Failure to do so may cause
damage to parts of the drive train, as well as dangerous handling 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 winter 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.
■When initializing the tire pressure warning system
Do not press the satellite 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 pressure is low, or it may come on when the tire inflation
pressure is actually normal.
NOTICE
■Repairing or replacing tires, wheels, ti re pressure warning valves, transmitters
and tire valve caps
●When removing or fitting the wheels, tires or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and
transmitter may be damaged if not handled correctly.
●When replacing tire valve caps, do not use tire valve caps other than those speci-
fied. The cap may become stuck.
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467
5-1. Essential information
IS350/250_U
Towing with a wheel lift-type truckFrom the front Vehicles with an automatic trans-
mission: Use a towing dolly under
the rear wheels.
Vehicles with a manual transmis-
sion: We recommend to use a tow-
ing dolly under the rear wheels.
When not using a towing dolly,
release the parking brake and shift
the shift lever to N.
From the rear (2WD models)Switch to ACCESSORY mode so
that the steering wheel is
unlocked.
From the rear (AWD models) Use a towing dolly under the front
wheels.
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477
5-2. Steps to take in an emergency
IS350/250_U
■If the tire pressure warning system is inoperative
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●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 regis-
tered in the tire pressure warning computer
●If a different set of tires has been selected using the satellite switch
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby
●If a radio set at similar frequencies is in use in the vehicle
●If there is a lot of snow or ice on the vehicle, in particular around the wheels or
wheel housings
●If non-genuine Lexus wheels are used (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used
■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 START STOP” switch is turned to IGNITION ON mode, have
it checked by your Lexus dealer.
■Customization that can be configured at Lexus dealer
The vehicle speed linked seat belt reminder buzzer can be disabled.
(Customizable features →P. 553)
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488
5-2. Steps to take in an emergency
IS350/250_U
Follow the correction procedures.After taking the specified steps to correct the suspected problem, check
that the warning light turns off.
InteriorbuzzerExterior buzzerWarning messageDetailsCorrection
procedure
Once
(Comes on for 10 seconds.)
(Flashing)
Indicates that an
attempt was made
to start the engine
without the elec-
tronic key being
present, or the
electronic key was
not functioning
normally.
Start the engine
with the elec-
tronic key
present.
*
Once3 times
(Flashing)
Indicates that a
door other than
the driver’s door
has been opened
or closed with the
“ENGINE START
STOP” switch in
any mode other
than OFF and the
electronic key
outside of the
detection area.
Confirm the loca-
tion of the elec-
tronic key.
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489
5-2. Steps to take in an emergency
IS350/250_U
Once3 times
(Vehicles with an auto-matic transmission)
(Flashing)
Indicates that the
driver’s door has
been opened or
closed with the
shift lever in P, the
“ENGINE START
STOP” switch in
any mode other
than OFF and the
electronic key
outside of the
detection area.
Tu r n t h e
“ENGINE START
STOP” switch
OFF or confirm
the location of the
electronic key.
OnceCon-
tinuous
(Displayed alternately)
(Vehicles with an auto-matic transmission)
(Flashing)
Indicates that the
driver’s door has
been opened or
closed (with the
shift lever out of in
P, t h e “ E N G I N E
START STOP”
switch in any
mode other than
OFF and the elec-
tronic key outside
of the detection
area).
• Shift the shift lever to P.
•Confirm the
location of the
electronic key.
Once
(Flashing)
Indicates that the
key battery is low.Replace the bat-
tery. ( →P. 4 3 3 )
Interior
buzzerExterior buzzerWa r n i n g m e s s a g eDetailsCorrection
procedure
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490
5-2. Steps to take in an emergency
IS350/250_U
Once
(Vehicles with an auto-matic transmission)
Indicates that a
door has been
opened or closed
and the “ENGINE
START STOP”
switch has been
switched twice to
ACCESSORY
mode from OFF.
Press the
“ENGINE START
STOP” switch
while applying the
brakes.
Once
(Vehicles with a manual
transmission)
Indicates that a
door has been
opened or closed
and the “ENGINE
START STOP”
switch has been
switched twice to
ACCESSORY
mode from OFF.
Press the
“ENGINE START
STOP” switch
while depressing
the clutch pedal.
(Flashing)
Indicates that the
steering lock has
not released
within 3 seconds
of pressing the
“ENGINE START
STOP” switch.Press the
“ENGINE START
STOP” switch
again while turn-
ing the steering
wheel with the
brake pedal
depressed.
InteriorbuzzerExterior buzzerWarning messageDetailsCorrection
procedure
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507
5-2. Steps to take in an emergency
IS350/250_U
Changing “ENGINE START STOP” switch modes and starting the engine
Automatic transmissionShift the shift lever to P and apply the brakes.
Touch the Lexus emblem side of
the electronic key to the
“ENGINE START STOP” switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
the “ENGINE START STOP”
switch if any of the doors is opened
and closed while the key is touched
to the switch.
To change “ENGINE START STOP” switch modes: Within 10
seconds of the buzzer sounding, release the brake pedal and
press the “ENGINE START STOP” switch. Modes can be
changed each time the switch is pressed.
(→P. 141)
To start the engine: Press the “ENGINE START STOP” switch
within 10 seconds after the buzzer sounds, keeping the brake
pedal depressed.
STEP1
STEP2
STEP3
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508
5-2. Steps to take in an emergency
IS350/250_UManual transmission
Shift the shift lever to N and depress the clutch pedal.
Touch the Lexus emblem side of
the electronic key to the
“ENGINE START STOP” switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
the “ENGINE START STOP”
switch if any of the doors is opened
and closed while the key is touched
to the switch.
To change “ENGINE START ST OP” switch modes: Within 10
seconds of the buzzer sounding, release the clutch pedal and
press the “ENGINE START STOP” switch. Modes can be
changed each time the switch is pressed.
(→ P. 141)
To start the engine: Press the “ENGINE START STOP” switch
within 10 seconds after the buzzer sounds, keeping the clutch
pedal depressed.
In the event that the engine still cannot be started, contact your Lexus
dealer.
STEP1
STEP2
STEP3