radiator cap Lexus GS450h 2008 Using the audio system / LEXUS 2008 GS450H OWNER'S MANUAL (OM30A96U)

420
4-3. Do-it-yourself maintenance
GS_HV_U
December 27, 2007 1:38 pm
Engine compartment
■12 volt battery
P. 4 3 0
Engine oil level dipstick 
( P. 422)
Engine oil filler cap 
( P. 423)
Brake fluid reservoir 
( P. 4 2 9 )
Fuse box ( P. 4 5 6 )Washer fluid tank 
( P. 4 3 4 )
Gasoline engine/power 
control unit coolant 
reservoir ( P. 4 2 7 )
Electric cooling fans
Condenser ( P. 4 2 8 )
Radiator ( P. 4 2 8 )

427
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U
December 27, 2007 1:38 pm
CoolantThe coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the hybrid system is cold.
Reservoir cap
“FULL”
“LOW”
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
■If the coolant level drops within a short time after replenishing
Visually check the radiator, hoses, reservoir 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 coolant, contact your Lexus dealer.

428
4-3. Do-it-yourself maintenance
GS_HV_U
December 27, 2007 1:38 pm
Radiator and condenserCheck the radiator and condenser and clear any foreign objects. 
If either of the above parts are extremely dirty or you are not sure of their
condition, have your vehicle checked by your Lexus dealer.
CAUTION
■When the hybrid system is hot
Do not remove the radiator and reservoir 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 the coolant
Coolant is neither plain water not 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 from damaging to parts or paint.
CAUTION
■When the hybrid system is hot
Do not touch the radiator or condenser, as they may be hot and you may be burned.

5
When trouble arises
539
5-2. Steps to take in an emergency
GS_HV_U
December 12, 2007 3:50 pm
■Overheating
In the following situations, 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.
●The message “HYBRID SYSTEM OVERHEAT” is displayed on the multi-infor-
mation display.
CAUTION
■To prevent an accident or injury when in specting under the hood of your vehicle
●Keep hands and clothing away from the fan and engine drive belt while the hybrid
system is running.
●Do not loosen the radiator cap while the hybrid system and radiator are hot. 
Serious injury, such as burns, may resu lt from hot coolant and steam released
under pressure.
Add coolant if necessary.
Water can be used in an emer-
gency measure if coolant is
unavailable. ( P. 5 4 8 )
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP6

589
Alphabetical index
GS_HV_U
December 12, 2007 3:50 pm
Parking brake .......................................... 147
Parking lightsReplacing light bulbs ........................474
Switch ....................................................... 158
Wattage ................................................. 552
Personal lights ....................................... 354
Power meter ............................................148
Power outlet ........................................... 368
Power windows......................................... 77
Pre-collision system ............................ 206
Radar cruise control ............................. 169
Radiator.................................................... 428
Radio ..........................................................244
Radio data system.................................246
Rear sunshade........................................372
Rear turn signal lights Replacing light bulbs ........................474
Wattage ................................................. 552
Rear view monitor system .................. 195
Rear window defogger ...................... 240
Replacing Electronic key battery ..................... 454
Fuses ........................................................ 456
Light bulbs .............................................474
Reporting safety defects for 
U.S. owners ......................................... 578
Seat belts Adjusting the seat belt ....................... 66
Automatic locking retractor............ 68
Child restraint system 
installation .............................................. 117
Cleaning and maintaining 
the seat belts..................................... 406 Emergency locking retractor..........68
How to wear your seat belt .............66
How your child should wear

the seat belt ..........................................69
Pre-collision seat belts .......................68
Pregnant women, 
proper seat belt use .........................68
Reminder light .....................................493
Seat belt extenders ..............................69
Seat belt pretensioners ...................... 67
Seat heaters/ventilators..................... 370
Seating capacity ....................................369
Seats Adjustment .............................................. 58
Adjustment precautions ....................59
Child seats/child restraint 
system installation.............................. 117
Cleaning ................................................ 405
Driver’s seat position memory .......60
Head restraint ......................................... 64
Properly sitting in the seat ................ 93
Seat heaters ......................................... 369
Service reminder indicators ............. 152
Shift lever If the shift lever cannot be 
shifted from P ...................................529
Transmission...........................................142
Shift lock system ....................................529
Shopping bag hooks............................ 375
Side airbags................................................ 95
Side marker lights Switch........................................................ 158
Side mirror Adjusting and folding.......................... 75
Mirror position memory ....................60P
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