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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U■
Selecting ID codes
When replacing tires, make sure to select the ID code set that matches
the new tire set. If the tire pressure select switch is set to the wrong tire
setting, the tire pressure warning system will not operate properly.
After driving for about 20 minutes, the tire pressure warning light
comes on after blinking for 1 minute to indicate a system malfunction.
Tire pressure warning valve and
transmitter ID code settings dis-
play
Press “<” or “>” repeatedly until
the setting display appears.
Switching ID codes
Press the “ON/OFF” button to
switch between “MAIN” and
“2ND” ID codes.
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4-3. Do-it-yourself maintenance
IS350/250_U
■When the initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following cases,
the settings have not been recorded and the system will not operate properly. If
repeated attempts to record tire inflation pressure settings are unsuccessful, have
the vehicle inspected by your Lexus dealer.
●When operating the satellite switch, the tire pressure warning light does not
blink 3 times.
●After carrying out the initialization procedure, the tire pressure warning light
blinks for 1 minute then stays on after driving for about 20 minutes.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.
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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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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
Checking and replacing fuses
If any of the electrical components do not operate, a fuse may have blown.
If this happens, check and replace the fuses as necessary.
Turn the “ENGINE START STOP” switch OFF.
Engine compartment (type B fuse box): Remove the engine
compartment cover. ( →P. 388)
Open the fuse box cover.
Engine compartment (type A fuse box)
Push the tabs in and lift the lid
off.
Engine compartment (type B fuse box) Push the tabs in and lift the lid
off.STEP1
STEP2
STEP3
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5-1. Essential information
IS350/250_U
Fuel pump shut off system
NOTICE
■Before starting the engine
Inspect the ground under the vehicle.
If you find that fuel has leaked on to the ground, the fuel system has been damaged
and is in need of repair. Do not restart the engine.
To minimize the risk of fuel leakage when the engine stalls or an airbag
inflates upon collision, the fuel pump shut off system stops supplying fuel to
the engine.
Follow the procedure below to restart the engine after the system is
activated.
Turn the “ENGINE START STOP” switch to the ACCESSORY
mode or OFF.
Restart the engine.
STEP1
STEP2
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When trouble arises
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5-2. Steps to take in an emergency
IS350/250_U
■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 lamp will go off after taking several driving trips.
If the lamp does not go off even after several trips, contact your Lexus dealer as
soon as possible.
■Electric power steering warning light
When the battery is low or when the voltage drops temporarily, the electric power
steering warning light may come on.
■Front passenger detection sensor and pass enger 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 a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pressing the
satellite switch does not turn off the tire pressure warning light.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with the tire pressure warning valve and
transmitter. If a tire goes flat, the tire pressure warning light will not turn off even
though the flat tire is replaced with the spare tire. Replace the spare tire with the
repaired tire and adjust the proper tire inflation pressure. The tire pressure warning
light will turn off after a few minutes.
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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 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 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. 5 4 0 )
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5-2. Steps to take in an emergency
IS350/250_U
Indicates that the trunk is
not fully closed. flashes and a
buzzer sounds to indi-
cate that trunk is not fully
closed (with the vehicle
having reached a speed
of 3 mph [5 km/h]).
Close the trunk.
(Flashing)
(If equipped)
Indicates that the moon
roof is not fully closed
(with the “ENGINE
START STOP” switch
OFF and the driver’s
door opened).
Close the moon roof.
Indicates that the parking
brake is still engaged.
flashes and a
buzzer sounds to indi-
cate that the parking
brake is still engaged
(with the vehicle having
reached a speed of 3
mph [5 km/h]).
Release the parking
brake.
Indicates that the washer
fluid level is low.Add washer fluid.
Wa r n i n g m e s s a g eDetailsCorrection procedure