Page 762 of 1014
7386-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Engine compartment
GS300h
12-volt battery
P. 7 4 9
Power control unit coolant
reservoir (P. 745)
Engine oil level dipstick
(P. 741)
Engine oil filler cap (P.
742)
Engine coolant reservoir
(P. 744)Fuse box (P. 782)
Washer fluid tank (P. 748)
Electric cooling fans
Condenser (P. 747)
Radiator (P. 747)1
2
3
4
5
6
7
8
9
Page 763 of 1014
739 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
GS450h
12-volt battery
P. 7 4 9
Engine oil level dipstick
(P. 741)
Engine coolant reservoir
(P. 744)
Engine oil filler cap (P.
742)
Power control unit coolant
reservoir (P. 745)Fuse box (P. 782)
Washer fluid tank (P. 748)
Electric cooling fans
Condenser (P. 747)
Radiator (P. 747)1
2
3
4
5
6
7
8
9
Page 770 of 1014

7466-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality eth-
ylene glycol based non-silicate, non-amine, non-nitrite, and non-borate cool-
ant with long-life hybrid organic acid technology.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50%
deionized water. (Minimum temperature: -35C [-31F])
For more details about coolant, contact any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/power control unit coolant reser-
voir caps, drain cock and water pump.
If you cannot find a leak, have any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional, test the cap and check for
leaks in the cooling system.
CAUTION
When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or the
coolant inlet cap. (P. 9 2 1 )
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 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 from damaging parts or paint.
Page 945 of 1014
9187-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
After the hybrid system has cooled down sufficiently, inspect
the hoses and cooling system for leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immediately contact your Lexus
dealer.
The coolant level is satisfactory if it is between the “FULL”
and “LOW” lines on the reservoir.
Reservoir
“FULL”
“LOW”
Coolant inlet cap
3
1
2
GS300hGS450h
4
1
2
3
4
GS300hGS450h
Page 951 of 1014

9247-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
When inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
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.
After the hybrid system has been turned off, check that the indicator on
the power switch and the “READY” indicator are off.
When the hybrid system is operating, the gasoline engine may automati-
cally start, or the cooling fan may suddenly operate even if the gasoline
engine stops. Do not touch or approach rotating parts such as the fan,
which may lead to fingers or clothing (especially a tie, a scarf or a muf-
fler) getting caught, resulting in serious injury.
Do not loosen the coolant inlet cap or
the coolant reservoir caps while the
hybrid system and radiator are hot.
High temperature steam or coolant
could spray out.
Page 1006 of 1014

974Alphabetical index
GS450h_300h_OM_OM30D53E_(EE)
Power control unit coolant ........744
Capacity ................................933
Checking ...............................744
Preparing and checking before
winter .................................434
Power easy access system .........199
Power outlets .............................700
Power steering ...........................398
Warning light........................833
Warning message..................845
Power switch .............................246
Power trunk lid ..........................187
Power windows .........................215
Door lock linked window
operation.............................217
Jam protection function ........216
Operation ..............................215
Window lock switch .............215
Pre-Crash Safety system (PCS) .406
Function ................................406
PCS OFF switch ...................408
Warning light........................833
Warning message..842, 855, 862
Radar cruise control (dynamic
radar cruise control) ........302, 319
Radiator .....................................747
Radio .........................................527
Radio Data System (RDS) ........532
Rear air conditioning system .....496
Rear door sunshades ..................712Rear fog light ............................ 283
Replacing light bulb............. 818
Switch .................................. 283
Rear personal lights .................. 685
Rear seat heaters ....................... 704
Rear sunshade ........................... 712
Operation ............................. 712
Reverse operation feature .... 713
Rear turn signal lights............... 267
Replacing light bulbs ........... 811
Turn signal lever .................. 267
Wattage ................................ 940
Rear view mirror
Inside rear view mirror ........ 208
Outside rear view mirrors .... 211
Rear view monitor system ........ 361
Rear window defogger ............ 501
Refueling .................................. 293
Capacity ............................... 929
Fuel types............................. 929
Opening the fuel tank cap .... 295
When the fuel filler door
cannot be opened ............... 296
Regenerative braking.................. 82
Remote Touch .......................... 442
Remote Touch screen .............. 445
Replacing
Electronic key battery .......... 779
Fuses .................................... 782
Light bulbs ........................... 803
Tires ..................................... 871
Road accident cautions ............... 88
R