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4-2. Maintenance
Maintenance requirements
■Repair and replacement
It is recommended that genuine Lexus parts be used for repair to ensure perfor-
mance of each system. If non-Lexus parts are used in replacement or if a repair
shop other than a Lexus dealer performs repairs, confirm the warranty coverage.
To ensure safe and economical driving, day-to-day care and regular main-
tenance is essential. It is the owner’s responsibility to perform regular
checks. Lexus recommends the following maintenance.
■General maintenance
Should be performed on a daily ba sis. This can be done by yourself
or by a Lexus dealer.
■ Scheduled maintenance
Should be performed at specified intervals according to the mainte-
nance schedule.
For details about maintenance items and schedules, refer to the
“Warranty and Services Guide/Owner’s Manual Supplement/
Scheduled Maintenance”.
■Do-it-yourself maintenance
You can perform some maintenance procedures yourself.
Please be aware that do-it-yourself maintenance may affect war-
ranty coverage.
The use of Lexus Repair Manuals is recommended.
For details about warranty coverage, see the separate “Owner’s Guide”,
“Warranty and Services Guide”, “Owner’s Manual Supplement” or
“Warranty Booklet”.
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4-2. Maintenance
4
Maintenance and care
10_IS250C/350C_U
■Allow inspection and repairs to be performed by a Lexus dealer
●Lexus technicians are well-trained specialists and are kept up to date with the
latest service information. They are well informed about the operations of all
systems on your vehicle.
●Keep a copy of the repair order. It proves that the maintenance that has been
performed is under warranty coverage. If any problem should arise while your
vehicle is under warranty, your Lexus dealer will promptly take care of it.
CAUTION
■If your vehicle is not properly maintained
It could result in serious damage to the vehicle and possible serious injury or death.
■Warning in handling of battery
●Engine exhaust, some of its constituents, and a wide variety of automobile com-
ponents contain or emit chemicals known to the State of California to cause can-
cer and birth defects and other reproductive harm. Work in a well ventilated area.
●Oils, fuels and fluids contained in vehicles as well as waste produced by compo-
nent wear contain or emit chemicals known to the State of California to cause
cancer and birth defects or other reproductive harm. Avoid exposure and wash
any affected area immediately.
●Battery posts, terminals and related accessories contain lead and lead com-
pounds which are known to cause brain damage. Wash your hands after han-
dling. (→P. 4 0 2 )
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4-2. Maintenance
10_IS250C/350C_U
General maintenance
Engine compartment
ItemsCheck points
BatteryMaintenance-free. (→P. 4 0 2 )
Brake fluidAt the correct level? ( →P. 4 0 0 )
Engine coolantAt the correct level? ( →P. 3 9 8 )
Engine oilAt the correct level? ( →P. 3 9 5 )
Exhaust systemNo fumes or strange sounds?
Radiator/condenser/hosesNot blocked with foreign matter?
(→ P. 4 0 0 )
Wa s h e r f l u i dAt the correct level? ( →P. 4 0 5 )
Listed below are the general maintenance items that should be performed
at the intervals specified in the “Warranty and Services Guide” or “Owners
Manual Supplement”. It is recommended that any problem you notice
should be brought to the attention of your Lexus dealer or qualified service
shop for advice.
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4-2. Maintenance
4
Maintenance and care
10_IS250C/350C_U
Emission inspection and maintenance (I/M) programs
Some states have vehicle emission inspection programs which include
OBD (On Board Diagnostics) checks. The OBD system monitors the oper-
ation of the emission control system.
■If the malfunction indicator lamp comes on
The OBD system determines that a problem exists somewhere in
the emission control system. Your vehicle may not pass the I/M test
and may need to be repaired. Cont act your Lexus dealer to service
the vehicle.
■ Your vehicle may not pass the I/M test:
●When the battery is disconnected or discharged
Readiness codes that are set du ring ordinary driving are erased.
Also, depending on your driving habits, the readiness codes may
not be completely set.
● When the fuel tank cap is loose
The malfunction indicator lamp comes on as a temporary mal-
function and your vehicle may not pass the I/M test.
■ When the malfunction indicator la mp goes off after several driv-
ing trips
The error code in the OBD system will not be cleared unless the
vehicle is driven 40 or more times.
■ If your vehicle does not pass the I/M test
Contact your Lexus dealer to prepare the vehicle for re-testing.
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4-3. Do-it-yourself maintenance
Do-it-yourself service precautions
If you perform maintenance yourself, be sure to follow the correct proce-
dure given in these sections.
ItemsParts and tools
Battery condition ( →P. 4 0 2)
•Warm water
• Baking soda
•Grease
•Conventional wrench
(for terminal clamp bolts)
Brake fluid level ( →P. 4 0 0 )
• FMVSS No.116 DOT 3 or SAE
J1703 brake fluid
•Rag or paper towel
• Funnel (used only for adding brake
fluid)
Engine coolant level ( →P. 3 9 8 )
• “Toyota Super Long Life Coolant”
or similar high-quality ethylene gly-
col-based non-silicate, non-amine,
non-nitrite and non-borate coolant
with long-life hybrid organic acid
technology.
For the U.S.A.:
“Toyota Super Long Life Coolant”
is pre-mixed with 50% coolant and
50% deionized water.
For Canada:
“Toyota Super Long Life Coolant”
is pre-mixed with 55% coolant and
45% deionized water.
• Funnel (used only for adding
engine coolant)
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4-3. Do-it-yourself maintenance
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Maintenance and care
10_IS250C/350C_U
■Engine oil consumption
●The amount of engine oil consumed depends on the oil viscosity, the quality of
the oil and the way the vehicle is driven.
●More oil is consumed under driving conditions such as high speeds and fre-
quent acceleration and deceleration.
●A new engine consumes more oil.
●When judging the amount of oil consumption, keep in mind that the oil may
have become diluted, making it difficult to judge the true level accurately.
●Oil consumption: Max. 1.1 qt./600 miles, 0.9 Imp. qt./600 miles (1.0 L per 1000
km)
●If your vehicle consume more than 1.1 qt. (1.0 L, 0.9 Imp. qt.) every 600 miles
(1000 km), contact your Lexus dealer.
■After changing the engine oil (U.S.A. only)
The oil change system should be reset. Perform the following procedures: Switch the display to the odometer ( →P. 159) when the engine is running.
Turn the “ENGINE START STOP” switch OFF.
While pressing the trip meter reset button, set the “ENGINE START
STOP” switch to the IGNITION ON mode (but do not start the engine
because otherwise the reset mode will be cancelled). Continue to press
and hold the button until the trip meter displays 000000.
CAUTION
■Used engine oil
●Used engine oil contains potentially harmful contaminants which may cause skin
disorders such as inflammation or skin cancer, so care should be taken to avoid
prolonged and repeated contact. To remove used engine oil from your skin, wash
thoroughly with soap and water.
●Dispose of used oil and filters only in a safe and acceptable manner. Do not dis-
pose of used oil and filters in househol d trash, in sewers or onto the ground.
Call your Lexus dealer, service station or auto parts store for information con-
cerning recycling or disposal.
●Do not leave used engine oil within the reach of children.
STEP1
STEP2
STEP3
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4-3. Do-it-yourself maintenance
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Maintenance and care
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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 death or serious injury.
NOTICE
■Replacing tire inflation pressure warning valves and transmitters
●Because tire repair or replacement may affect the tire pressure warning valves
and transmitters, make sure to have tires serviced by your Lexus dealer or other
qualified service shop. In addition, make sure to purchase your tire pressure
warning valves and transmitters at your Lexus dealer.
●Ensure that only genuine Lexus wheels are used on your vehicle.
Tire pressure warning valves and transmitters may not work properly with non-
genuine wheels.
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6-1. Specifications
10_IS250C/350C_U
■Lexus does not recommend gasoline containing MMT
Some gasoline contains octane enhancing additive called MMT (Methylcyclopen-
tadienyl Manganese Tricarbonyl).
Lexus DOES NOT recommend the use of gasoline that contains MMT. If fuel con-
taining MMT is used, your emission control system may be adversely affected.
The malfunction indicator lamp on the inst rument cluster may come on. If this hap-
pens, contact your Lexus dealer for service.
NOTICE
■Notice on fuel quality
●Do not use improper fuels. If improper fuels are used the engine will be damaged.
●Do not use leaded gasoline.
Leaded gasoline can cause damage to your vehicle’s three-way catalytic convert-
ers causing the emission control system to malfunction.
●Do not use gasohol other than that stated here.
Other gasohol may cause fuel system damage or vehicle performance problems.
●IS250C: Use of unleaded gasoline with an octane rating lower than 91 may result
in engine knocking. Persistent knocking can lead to engine damage and should
be corrected by refueling with higher octane unleaded gasoline.
●IS350C: Use of unleaded gasoline with an octane rating lower than 91 may result
in engine knocking and significantly reduced performance. Persistent knocking
can lead to engine damage and should be corrected by refueling with higher
octane unleaded gasoline.
■Fuel-related poor driveability
If after using a different type of fuel, poor driveability is encountered (poor hot start-
ing, vaporization, engine knocking, etc.), discontinue the use of that type of fuel.
■When refueling with gasohol
Take care not to spill gasohol. It can damage your vehicle's paint.