Page 417 of 626
416
4-3. Do-it-yourself maintenance
IS250C/350C_U
Engine compartment
IS350C
Battery (→P. 4 2 7 )
Engine oil level dipstick (→P. 4 2 0 )
Engine oil filler cap (→P. 4 2 0 )
Brake fluid reservoir (→P. 425)
Fuse boxes ( →P. 4 5 1 )Washer fluid tank
(→P. 4 3 0 )
Electric cooling fans
Condenser ( →P. 425)
Radiator ( →P. 425)
Engine coolant reservoir (→P. 423)
Page 418 of 626
417
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS250C/350C_U
IS250C
Battery (→P. 4 2 7 )
Engine oil level dipstick (→P. 4 2 0 )
Engine oil filler cap (→P. 4 2 0 )
Brake fluid reservoir (→P. 425)
Fuse boxes ( →P. 4 5 1 )Washer fluid tank
(→P. 4 3 0 )
Electric cooling fans
Condenser ( →P. 425)
Radiator ( →P. 425)
Engine coolant reservoir (→P. 423)
Page 425 of 626

424
4-3. Do-it-yourself maintenance
IS250C/350C_U
■If the coolant level drops within a short time after replenishing
Visually check the radiator, hoses, engine coolant filler cap, radiator cap, drain cock
and water pump.
If you cannot find a leak, have your Lexus dealer pressure test the cap and check for
leaks in the cooling system.
■Coolant selection
Only use “Toyota Super Long Life Coolant” or similar high-quality ethylene glycol-
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life
hybrid organic acid technology.U.S.A.: “Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deionized water. (Enabled: -31 °F [-35 °C])
Canada: “Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deionized water. (Enabled: -44 °F [-42 °C])
For more details about engine coolant, contact your Lexus dealer.
CAUTION
■When the engine is hot
Do not remove the radiator cap.
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing serious injuries, such as burns.
NOTICE
■When adding engine coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of water
and antifreeze must be used to provide proper lubrication, corrosion protection
and cooling. Be sure to read the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to prevent it damaging parts or paint.
Page 538 of 626

5
When trouble arises
537
5-2. Steps to take in an emergency
IS250C/350C_U
■Overheating
If you observe the following, your vehicle may be overheating.
●The engine coolant temperature gauge enters the red zone or a loss of power is
experienced.
●Steam is coming from under the hood.
CAUTION
■To prevent an accident or injury when inspecting under the hood of your vehicle
●If steam is seen coming from under the hood, do not open the hood until the
steam has subsided. The engine compartment may be very hot, causing serious
injury such as burns.
●Keep hands and clothing away from the fan and other belts while the engine is
running.
●Do not loosen the radiator cap while the engine and radiator are hot.
Serious injury, such as burns, may result from hot coolant and steam released
under pressure.
Add engine coolant if required.
Water can be used in an emer-
gency measure if engine coolant
is unavailable. (→P. 5 5 9 )
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP5