Page 409 of 586

4087-2. Maintenance
IS350/250_U (OM53C50U)
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. Contact your Lexus dealer to service the vehicle.
●When the battery is disconnected or discharged
Readiness codes that are set during ordinary driving are erased.
Also, depending on your driving habits, the readiness codes may not be com-
pletely set.
●When the fuel tank cap is loose
The malfunction indicator lamp comes on indicating a temporary malfunction
and your vehicle may not pass the I/M test.
The error code in the OBD system will not be cleared unless the vehicle is driven
40 or more times.
Contact your Lexus dealer to prepare the vehicle for re-testing.
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 operation of
the emission control system.
If the malfunction indicator lamp comes on
Your vehicle may not pass the I/M test in the following situations:
When the malfunction indicator lamp still remains on after several driv-
ing trips
If your vehicle does not pass the I/M test
Page 410 of 586

409
IS350/250_U (OM53C50U)
7
Maintenance and care
7-3. Do-it-yourself maintenance
Do-it-yourself service precautions
If you perform maintenance by yourself, be sure to follow the correct proce-
dure as given in these sections.
ItemsParts and tools
Battery condition
(→ P. 4 2 0 )•Warm water• Baking soda•Grease
• Conventional wrench (for terminal clamp bolts)
Brake fluid level
(→ P. 4 1 9 )• SAE J1703 or FMVSS No.116 DOT 3 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine coolant level
(→ P. 4 1 7 )
• “Toyota Super Long Life Coolant” or a similar high quality
ethylene glycol-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 coolant)
Engine oil level
(→ P. 4 1 4 )• “Toyota Genuine Motor Oil” or equivalent
• Rag or paper towel
• Funnel (used only for adding engine oil)
Fuses
(→ P. 4 4 1 )• Fuse with same amperage rating as original
Light bulbs
(→ P. 444)
• Bulb with same number and wattage rating as original
• Phillips-head screwdriver•Flathead screwdriver
•Wrench
Radiator and con-
denser ( →P. 4 1 8 )
Tire inflation pres-
sure ( →P. 4 3 2 )• Tire pressure gauge• Compressed air source
Wa s h e r f l u i d
(→ P. 4 2 2 )• Water or washer fluid containing antifreeze (for winter use)
• Funnel (used only for adding water or washer fluid)
Page 411 of 586

4107-3. Do-it-yourself maintenance
IS350/250_U (OM53C50U)
CAUTION
The engine compartment contains many mechan isms and fluids that may move suddenly,
become hot, or become electrically energize d. To avoid death or serious injury, observe
the following precautions.
■When working on the engine compartment
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, radiator, exhaust manifold, etc. right after driving
as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel and
battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and corro-
sive sulfuric acid.
■When working near the electric cooling fans or radiator grille
Be sure the engine switch is off.
With the engine switch in IGNITION ON mode, the electric cooling fans may auto-
matically start to run if the air conditioning is on and/or the coolant temperature is high.
( → P. 4 1 8 )
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting in
your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to dirt
in the air.
Page 412 of 586
4117-3. Do-it-yourself maintenance
7
Maintenance and care
IS350/250_U (OM53C50U)
Pull the hood lock release lever.
The hood will pop up slightly.
Pull up the auxiliary catch lever and
lift the hood.
Hood
Release the lock from the inside of the vehicle to open the hood.
1
2
CAUTION
■Pre-driving check
Check that the hood is fully closed and locked.
If the hood is not locked properly, it may open while the vehicle is in motion and cause
an accident, which may result in death or serious injury.
Page 413 of 586
4127-3. Do-it-yourself maintenance
IS350/250_U (OM53C50U)
◆Front 2WD models
AW D m o d e l s
◆Rear
Positioning a floor jack
When using a floor jack, follow the instructions in the manual provided with
the jack and perform the operation safely.
When raising your vehicle with a floo r jack, position the jack correctly.
Improper placement may damage your vehicle or cause injury.
1
2
Page 414 of 586
4137-3. Do-it-yourself maintenance
7
Maintenance and care
IS350/250_U (OM53C50U)
Engine compartment
Fuse boxes (→P. 4 4 1 )
Battery ( →P. 4 2 0 )
Engine oil level dipstick (→ P. 4 1 4 )
Engine coolant reservoir (→ P. 4 1 7 )
Engine oil filler cap (→ P. 4 1 5 )Brake fluid reservoir (
→P. 4 1 9 )
Wa s h e r f l u i d t a n k ( →P. 422)
Electric cooling fans
Condenser ( →P. 4 1 8 )
Radiator ( →P. 4 1 8 )1
2
3
4
5
6
7
8
9
10
Page 415 of 586
4147-3. Do-it-yourself maintenance
IS350/250_U (OM53C50U)
With the engine at operating temperature and turned off, check the oil level on
the dipstick.
■Checking the engine oil Park the vehicle on level ground. Afte r warming up the engine and turning
it off, wait more than 5 minutes for the oil to drain back into the bottom of
the engine.
Holding a rag under the end, pull
the dipstick out.
Wipe the dipstick clean.
Reinsert the dipstick fully.
Holding a rag under the end, pull
the dipstick out and check the oil
level.
Low
Normal
Excessive
The shape of the dipstick may dif-
fer depending on the type of vehi-
cle or engine.
Wipe the dipstick and reinsert it fully.
Engine oil
1
2
3
4
5
1
2
3
6
Page 416 of 586

4157-3. Do-it-yourself maintenance
7
Maintenance and care
IS350/250_U (OM53C50U)
■Adding engine oil
If the oil level is below or near the
low level mark, add engine oil of the
same type as that already in the
engine.
Make sure to check the oil type and prepare the items needed before adding
oil.Remove the oil filler cap by turning it counterclockwise.
Add engine oil slowly, checking the dipstick.
Install the oil filler cap by turning it clockwise.
■Engine oil consumption
A certain amount of engine oil will be consumed while driving. In the following situations,
oil consumption may increase, and engine oil may need to be refilled in between oil
maintenance intervals.
●When the engine is new, for example direct ly after purchasing the vehicle or after
replacing the engine
●If low quality oil or oil of an inappropriate viscosity is used
●When driving at high engine speeds or with a heavy load, or when driving while accel-
erating or decelerating frequently
●When leaving the engine idling for a long time, or when driving frequently through
heavy traffic
Engine oil selection →P. 5 1 5
Oil quantity (Low → Full) 1.6 qt. (1.5 L, 1.3 Imp. qt.)
Items Clean funnel
1
2
3