engine coolant Lexus GS300h 2015 User Guide

4266-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F00E_(EE)
■Coolant selection
Only use “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.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deionized water.
(Minimum temperature: -35 °C [-31 °F])
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 reservoir 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 sys-
tem.
WA R N I N G
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or the coolant
inlet cap. ( →P. 5 6 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 cool-
ing. 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.

475
7
7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30F00E_(EE)
If you think something is wrong
●Fluid leaks under the vehicle.
(Water dripping from the air conditioning after use is normal.)
●Flat-looking tires or uneven tire wear
●Engine coolant temperature gauge needle continually points higher than nor-
mal.
●Changes in exhaust sound
●Excessive tire squeal when cornering
●Strange noises related to the suspension system
●Pinging or other noises related to the hybrid system
●Engine missing, stumbling or running roughly
●Appreciable loss of power
●Vehicle pulls heavily to one side when braking
●Vehicle pulls heavily to one side when driving on a level road
●Loss of brake effectiveness, spongy feeling, pedal almost touches the floor
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact any authorized Lexus dealer or repairer, or
another duly qualified an
d equipped professional as soon as possible.
Visible s ymp toms
Audible symptoms
Operational symptoms

4927-2. Steps to take in an emergency
GS450h_300h_OM_OM30F00E_(EE)
Indicates a malfunction in:•The ABS; or
• The brake assist system
A buzzer also sounds.
→ Immediately stop the vehicle in a safe place and
contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Indicates that the engine coolant temperature is too high
A buzzer also sounds.
→ P. 5 5 6
Indicates a malfunction in the vehicle’s charging system.
→Immediately stop the vehicle in a safe place and
contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Wa r n i n g m e s s a g eDetails/Actions

5567-2. Steps to take in an emergency
GS450h_300h_OM_OM30F00E_(EE)
If your vehicle overheats
●The needle of the engine coolant temperature gauge ( →P. 104) enters the
red zone or a loss of hybrid system power is experienced. (For example, the
vehicle speed does not increase.)
●“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” or
“Hybrid System Overheated Reduced Output Power” ( →P. 482) is shown on
the multi-information display.
●Steam comes out from under the hood.
■If the needle of the engine coolant temperature gauge enters the red zone
or “Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” is
shown on the multi-information display
Stop the vehicle in a safe place and turn off the air conditioning system, and
then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
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 any autho-
rized Lexus dealer or repairer, or
another duly qualified and
equipped professional.
The following may indicate that your vehicle is overheating.
Correction procedures
1
2
3
1
2

5577-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F00E_(EE)
The coolant level is satisfactory if it is between the “FULL” and “LOW” lines
on the reservoir.Reservoir
“FULL”
“LOW”
Coolant inlet cap
Add coolant if necessary. ( →P. 5 6 0 )
Water can be used in an emergency if engine coolant is unavailable.
4
1
2
3
4
XGS450hXGS300h
5
XGS450hXGS300h

5617-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F00E_(EE)
WA R N I N G
■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 automatically 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 muffler) ge tting caught, resulting in serious injury.
●Do not loosen the coolant inlet cap or the
coolant reservoir caps while the hybrid sys-
tem and radiator are hot.
High temperature steam or coolant could
spray out.XGS450h
XGS300h

5627-2. Steps to take in an emergency
GS450h_300h_OM_OM30F00E_(EE)
NOTICE
■When adding engine/power control unit coolant
Add coolant slowly after the hybrid system has cooled down sufficiently. Adding cool
coolant to a hot hybrid system too quickly can cause damage to the hybrid system.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust etc.).
●Do not use any coolant additive.

5728-1. Specifications
GS450h_300h_OM_OM30F00E_(EE)
Cooling system
Gasoline engine
Power control unit
Left-hand drive vehiclesRight-hand drive vehicles
Capacity
GS450h9.2 L (9.7qt.,
8.1 Imp.qt.)2.1 L (2.2qt.,
1.8 Imp.qt.)1.9 L (2.0qt.,
1.7 Imp.qt.)
GS300h8.1 L (8.6 qt.,
7.1 Imp.qt.)1.6 L (1.7 qt.,
1.4 Imp.qt.)1.8 L (1.9 qt.,
1.6 Imp.qt.)
Coolant typeUse either of the following:• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-sili-cate, non-amine, non-nitrite, and non-borate cool-
ant with long-life hybrid organic acid technology
Do not use plain water alone.
Ignition system
Spark plug
Make
GapDENSO FK20HBR8
0.8 mm (0.031 in.)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.

604Alphabetical index
GS450h_300h_OM_OM30F00E_(EE)
Cargo hooks........................................... 394
CD player
*
Chains .......................................................355
Child restraint system ............................ 56Baby seats, definition .......................... 57
Baby seats, installation ....................... 66
Child seats, definition.......................... 57
Child seats, installation....................... 66
Installing CRS with ISOFIX rigid anchors........................................ 69
Installing CRS with seat belts.......... 66
Installing CRS with top strap .......... 70
Junior seats, definition ........................ 57
Junior seats, installation .....................68
Child safety................................................. 55 12-volt battery
precautions........................... 430, 555
Airbag precautions .............................. 45
Child restraint system......................... 56
How your child should
wear the seat belt ..................... 39, 40
Installing child restraints .................... 65
Moon roof precautions ................... 198
Power window lock switch.............193
Power window precautions .......... 195
Rear door child-protectors ............143
Removed electronic key battery precautions ....................... 452
Seat belt comfort guide ..................... 39
Seat belt precautions .......................... 42
Seat heater precautions .................. 381
Trunk precautions ..............................149
Child-protectors ................................... 143 Cleaning.........................................406, 410
Aluminum wheels.............................. 407
Exterior ................................................... 406
Interior.......................................................410
Seat belts ................................................... 411
Clock ...............................................105, 398
Coat hooks.............................................. 402
Condenser ..............................................427
Console box ........................................... 390
Console box light ...................................391
Coolant..................................................... 425 Capacity..................................................572
Checking ............................................... 425
Preparing and checking
before winter.................................... 354
Cooling system ..................................... 425
Engine overheating .......................... 556
Hybrid system overheating.......... 556
Consumption screen ........................... 126
Cruise control Cruise control ......................................327
Dynamic radar cruise control ....... 315
Dynamic radar cruise control with full-speed range ................... 303
Cup holders ..............................................391
Curtain shield airbags .......................... 43
Customizable features........................ 581

606Alphabetical index
GS450h_300h_OM_OM30F00E_(EE)
Dynamic radar cruise control with full-speed range .......................303
Function ..................................................303
Warning message.............................482
Dynamic Rear Steering (DRS)........345 Function ..................................................345
Warning message.............................482
DVD player
*
Eco drive mode .....................................330
Electric motor (traction motor) ......... 75
Electric Power Steering (EPS)........345 Function ..................................................345
Warning light ....................................... 477
Warning message.............................482
Electronic key.......................................... 134 Battery-saving function.................... 155
If the electronic key does not operate properly ........................... 548
Replacing the battery.........................451
Emergency, in case of
If a warning buzzer sounds .......... 476
If a warning light turns on............... 476
If a warning message is displayed ............................................ 482
If the 12-volt battery is discharged.......................................... 551
If the electronic key does not operate properly ........................... 548
If the hybrid system will not start ........................................................543
If the parking brake cannot be released........................................546 If the shift lever cannot be
shifted from P................................... 545
If you have a flat tire................517, 528
If you think something is wrong .............................................. 475
If your vehicle becomes stuck .... 563
If your vehicle has to be stopped in an emergency ......... 469
If your vehicle needs to be towed ............................................ 470
If your vehicle overheats................ 556
Emergency brake signal.................... 345
Emergency flashers............................. 468
Emergency tire puncture
repair kit ................................................ 528
Energy monitor ....................................... 126
Engine ....................................................... 568 Accessory mode ................................. 218
Compartment ....................................... 419
Engine switch ........................................ 217
Hood ......................................................... 417
How to start the hybrid
system.................................................... 217
Identification number.......................568
Ignition switch (power switch) .................................. 217
Overheating ........................................ 556
Power switch ......................................... 217
Engine compartment cover ...............421
Engine coolant....................................... 425 Capacity..................................................572
Checking ............................................... 425
Preparing and checking before winter.................................... 354
E