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4-3. Do-it-yourself maintenance
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■Tire types
1 Summer tiresSummer tires are high-speed performance tires best suited to highway driving
under dry conditions. Since summer tires do not have the same traction perfor-
mance as snow tires, summer tires are inadequate for driving on snow-covered
or icy roads. For driving on snow-covered roads or icy roads, the use of snow tires
is recommended. When installing snow tires, be sure to replace all four tires.
2 All season tires All season tires are designed to provide better traction in snow and to be ade-
quate for driving in most winter conditions, as well as for use year round. All sea-
son tires, however, do not have adequate traction performance compared with
snow tires in heavy or loose snow. Also, al l season tires fall short in acceleration
and handling performance compared with summer tires in highway driving.
3Snow tires For driving on snow-covered roads or icy roads, we recommend using snow tires.
If you need snow tires, select tires of the same size, construction and load capac-
ity as the originally installed tires. Since your vehicle has radial tires as original
equipment, make sure your snow tires also have radial construction. Do not install
studded tires without first checking local regulations for possible restriction.
Snow tires should be installed on all wheels. (
→P. 1 8 3 )
■Initializing the tire pressure warning system
Initialize the tires with the tire inflation pressure adjusted to the specified level.
■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 tire pressure warning reset switch, the tire pressure warn-
ing light does not flash 3 times and the setting message does not appear on the
multi-information display.
●After driving for a certain period of time since the initialization has been com-
pleted, the tire pressure warning light comes on after blinking for 1 minute.
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5-2. Steps to take in an emergency
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■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel 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.
■Front passenger detection sensor and passenger 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
tire pressure warning reset switch does not turn off the tire pressure warning light.
■The tire pressure warning light ma y 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 tires 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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When trouble arises
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5-2. Steps to take in an emergency
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■The compact spare tire
●The compact spare tire is identified by the label “TEMPORARY USE ONLY”
on the tire sidewall.
Use the compact spare tire temporarily only in an emergency.
●Make sure to check the tire pressure of the compact spare tire. (→P. 4 1 5 )
■When using the compact spare tire
As the compact spare tire is not equipped with the tire pressure warning valve and
transmitter, low inflation pressure of the spare tire will not be warned. Also, if you
replace the compact spare tire after the tire pressure warning light comes on, the
light remains on.
■If you have a flat rear tire on a road covered with snow or ice
Install the compact spare tire on the front of the vehicle. Perform the following steps
and fit tire chains to the rear tires.Replace a front tire with the compact spare tire.
Replace the flat rear tire with the tire removed from the front of the vehi-
cle.
Fit tire chains to the rear tires.
■After completing the tire change
The tire pressure warning system must be reset. (
→P. 3 0 8 )
STEP1
STEP2
STEP3