2010 Lexus IS250 radiator cap

400
4-3. Do-it-yourself maintenance
IS350/250_U
Engine compartment
IS350
Battery (→P. 4 1 0 )
Engine oil level dipstick (→P. 403)
Engine oil filler cap (→P. 403)
Brake fluid reservoir (→P. 4 0 8 )
Fuse boxes ( →P. 4 3 6 )Washer fluid tank
(→P. 413)
Electric cooling fans
Condenser ( →P. 4 0 8 )
Radiator ( →P. 4 0 8 )
Engine coolant reservoir (→P. 4 0 6 )

401
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
IS250
Battery (→P. 4 1 0 )
Engine oil level dipstick (→P. 403)
Engine oil filler cap (→P. 403)
Brake fluid reservoir (→P. 4 0 8 )
Fuse boxes ( →P. 4 3 6 )Washer fluid tank
(→P. 413)
Electric cooling fans
Condenser ( →P. 4 0 8 )
Radiator ( →P. 4 0 8 )
Engine coolant reservoir (→P. 4 0 6 )

407
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_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 burns or other injuries.
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.

5
When trouble arises
513
5-2. Steps to take in an emergency
IS350/250_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 fans 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 if engine coolant is
unavailable. (→P. 5 2 4 )
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP6

570
Alphabetical index
IS350/250_U
Parking assist sensors .......................... 190
Parking brake .......................................... 148
Parking lightsReplacing light bulbs........................ 452
Switch ....................................................... 165
Wattage.................................................. 533
PCS ............................................................202
Personal lights Switch ........................................................ 331
Power outlet............................................ 347
Power windows ........................................ 76
Pre-collision system.............................202
Radar cruise control ............................. 179
Radiator ................................................... 408
Radio .......................................................... 233
RDS ............................................................235
Rear sunshade .......................................355
Rear turn signal lights Replacing light bulbs........................ 452
Wattage.................................................. 533
Rear view mirror
Compass ............................................... 369
Rear window defogger.......................228
Replacing Electronic key battery...................... 434
Fuses ........................................................ 436
Light bulbs............................................. 452
Reporting safety defects for U.S. owners ......................................... 558 Safety Connect ..................................... 373
Scuff lights................................................ 329
Seat belts
Adjusting the seat belt ........................63
Automatic locking retractor ............64
Child restraint system
installation .............................................. 113
Cleaning and maintaining
the seat belts .................................... 386
Emergency locking retractor..........64
How to wear your seat belt .............62
How your child should wear
the seat belt.......................................... 65
Pregnant women,
proper seat belt use .........................64
Reminder light......................................473
Seat belt extenders.............................. 65
Seat belt pretensioners ......................63
Seat heaters ..................................348, 351
Seat position memory............................ 57
Seat ventilators ....................................... 351
Seating capacity.................................... 209
Seats Adjustment ................................................ 51
Adjustment precautions ....................52
Child seats/child restraint
system installation .............................. 113
Cleaning ................................................ 385
Driver’s seat position memory .......53
Front passenger seat position
memory ..................................................57
Head restraint ........................................ 59
Properly sitting in the seat.................. 91
Seat heaters ...............................348, 351
Ventilated seats.................................... 351
Service reminder indicators .............157P
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