2007 Lexus IS250 Basic Functions / LEXUS 2007 IS350/250 OWNER'S MANUAL (OM53578U)

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4-3. Do-it-yourself maintenance
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Maintenance and care
■Effects of incorrect tire inflation pressure
Driving with incorrect tire pressure may result in the following:
●Reduced fuel efficiency
●Reduced driving comfort and tire life
●Reduced safety
●Damage to the drive train
If a tire needs frequent refilling, have it checked by your Lexus dealer.
■Instructions for checking tire pressure
When checking tire inflation pressure, observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at least 3 hours and has not been driven for
more than 1 mile or 1.5 km, you will get an accurate cold tire inflation pressure
reading.
●Always use a tire pressure gauge.
The appearance of the tire can be misleading. In addition, tire inflation pressures
that are even just a few pounds off can degrade ride and handling.
●Do not bleed or reduce tire inflation pressure after driving. It is normal for the
tire inflation pressure to be higher after driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle is bal-
anced.

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4-3. Do-it-yourself maintenance
CAUTION
■Proper inflation is critical to save tire performance
Keep your tires properly inflated. Otherwise, the following conditions may occur
and result in an accident causing death or serious injury.
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overheated tires
●Poor sealing of the tire bead
●Wheel deformation and/or tire separation
●A greater possibility of tire damage from road hazards
NOTICE
■When inspecting and adjusting tire pressure
Be sure to reinstall the tire valve caps.
Without the valve caps, dirt or moisture could get into the valve and cause air leak-
age, which could result in an accident. If the caps have been lost, replace them as
soon as possible.

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Maintenance and care
Wheels
■When replacing wheels
The wheels of your Lexus are equipped with sensors that allow the tire pressure
warning system sensors to provide advanced warning in the event of a loss in tire
pressure. Whenever wheels are replaced, the tire inflation pressure sensors must
be switched over from the old wheels. (P. 2 8 5 )
If a wheel is bent, cracked or heavily corroded, it should be replaced. Oth-
erwise, the tire may separate from the wheel or cause loss of handling con-
trol.
■Wheel selection
When replacing wheels, care should be taken to ensure that they
are equivalent to those removed in load capacity, diameter, rim
width, and offset.
Replacement wheels are available at your Lexus dealer.
Lexus does not recommend using:
• Wheels of different sizes or types
• Used wheels
• Bent wheels that have been straightened
■Aluminum wheel precautions
●Use only Lexus wheel nuts and wrenches designed for use with
your aluminum wheels.
●When rotating, repairing or changing your tires, check that the
wheel nuts are still tight after driving 1000 miles (1600 km).
●Be careful not to damage the aluminum wheels when using tire
chains.
●Use only Lexus genuine balance weights or equivalent and a
plastic or rubber hammer when balancing your wheels.

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4-3. Do-it-yourself maintenance
CAUTION
■When replacing wheels
●Do not use wheels that are a different size from those recommended in the
Owner’s Manual, as this may result in loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a tubeless tire.
Doing so may result in an accident, causing serious injury or death.
NOTICE
■Replacing tire inflation pressure sensors
●Because tire repair or replacement may affect the tire pressure sensors, make
sure to have tires serviced by your Lexus dealer or other qualified service shop. In
addition, make sure to purchase your tire pressure sensors at your Lexus dealer.
●Ensure that only Genuine Lexus wheels are used on your vehicle.
Tire pressure sensors may not work properly with non-genuine wheels.

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4-3. Do-it-yourself maintenance
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Maintenance and care
Air conditioning filter
The air conditioning filter must be cleaned or changed regularly to main-
tain air conditioning efficiency.
■Removal method
Set the air conditioning system to recirculated mode.
The air conditioning filter case cannot be removed with the system in
the outside air mode.
Turn the engine switch OFF.
Open the glove box. Lift and
remove the partition.
Remove the filter cover.
Remove the filter case.
STEP1
STEP2
STEP3
STEP4
STEP5

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4-3. Do-it-yourself maintenance
■Checking interval
Inspect and replace the air conditioning filter according to the maintenance sched-
ule. In dusty areas or areas with heavy traffic flow, early replacement may be
required. (For scheduled maintenance information, please refer to the "Owner's
Manual Supplement/Scheduled Maintenance".)
■If air flow from the vents decreases dramatically
The filter may be clogged. Check the filter and replace if necessary.
■Cleaning method
If the filter is dirty, clean by blow-
ing compressed air through the
filter from the downward side.
Hold the air gun 2 in. (5 cm)
from the filter and blow for
approximately 2 minutes at
72 psi (500 kPa, 5.0 kgf/cm
2
or bar).
If it is not available, have the
filter cleaned by your Lexus
dealer.
■Replacement method
Remove the air conditioning fil-
ter from the filter case and
replace it with a new one.
The UP marks shown on the
filter and the filter case should
be pointing up.

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Maintenance and care
NOTICE
■To prevent damage to the system
●When using the air conditioning system, make sure that a filter is always installed.
●When cleaning the filter, do not clean the filter with water.

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4-3. Do-it-yourself maintenance
Electronic key battery
Replace the battery with a new one if it is discharged.
■You will need the following items:
●Flathead screwdriver
●Small Phillips-head screwdriver
●Lithium battery (CR1632)
■Replacing the battery
Take out the mechanical key.
Remove the cover.
Remove the depleted battery.
Insert a new battery with the +
terminal facing up.
STEP1
STEP2
STEP3