2018 Lexus GS450h radiator

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GS450h_OM_OM30G62U_(U)6-2. Maintenance
6
Maintenance and care
General maintenance
Listed below are the general maintenanc e items that should be performed at
the intervals specified in the “Warranty and Service Guide” or “Owner’s
Manual Supplement”. It is recommende d that any problem you notice should
be brought to the attention of your Lexu s dealer or qualified service shop for
advice.
Engine compartment
ItemsCheck points
Brake fluidIs the brake fluid at the correct level? ( →P. 360)
Engine/power control unit
coolantIs the engine/power control unit coolant at the cor-
rect level? ( →P. 358)
Engine oilIs the engine oil at the correct level? ( →P. 355)
Exhaust systemThere should not be any fumes or strange sounds.
Radiator/condenserThe radiator and condenser should be free from for-
eign objects. ( →P. 359)
Washer fluidIs there sufficient washer fluid? (→ P. 361)
Trunk
ItemsCheck points
12-volt batteryCheck the connections. (→P. 362)

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GS450h_OM_OM30G62U_(U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Do-it-yourself service precautions
*: Vehicles with sing le-beam headlights
If you perform maintenance by yourself, be sure to follow the correct proce-
dure as given in these sections.
ItemsParts and tools
12-volt battery con-
dition (→P. 362)•Grease
• Conventional wrench (for terminal clamp bolts)
Brake fluid level
(→ P. 360)
• FMVSS No.116 DOT 3 or SAE J1703 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine/power con-
trol unit coolant level
(→ P. 358)
•“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
For the U.S.A.:
“Toyota Super Long Life Coolant” is pre-mixed with 50%
coolant and 50% deionized water.
For Canada:
“Toyota Super Long Life Cool ant” is pre-mixed with 55%
coolant and 45% deionized water.
• Funnel (used only for adding coolant)
Engine oil level
( → P. 355)
• “Toyota Genuine Motor Oil” or equivalent
• Rag or paper towel
• Funnel (used only for adding engine oil)
Fuses ( →P. 384)• Fuse with same amperage rating as original
Headlight aim*
( → P. 389)• Phillips-head screwdriver
Light bulbs
(→ P. 391)
• Bulb with same number and wattage rating as original
• Phillips-head screwdriver•Flathead sc rewdriver
•Wrench
Radiator and con-
denser (→P. 359)⎯
Tire inflation pres-
sure (→P. 375)• Tire pressure gauge• Compressed air source
Washer fluid
(→ P. 361)• Water or washer fluid containing antifreeze (for winter use)
• Funnel (used only for adding water or washer fluid)

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GS450h_OM_OM30G62U_(U)
6-3. Do-it-yourself maintenance
WARNING
The engine compartment contains many mechanisms and fluids that may move suddenly,
become hot, or become electrically energize d. To avoid death or serious injury, observe
the following precautions.
■When working on the engine compartment
●Make sure that the “POWER ON” on the multi-information display and the
“READY” indicator are both off.
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, power co ntrol unit, radiator, exhaust manifold, etc.
right after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flamma-
ble.
■When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automatically start to
run if the air conditioning is on and/ or the coolant temperature is high. ( →P. 359)
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting in
your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner f ilter removed may cause excessive engine wear due to dirt
in the air.

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GS450h_OM_OM30G62U_(U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Engine compartment
■12-volt battery
→ P. 362
Engine oil level dipstick
(→P. 355)
Engine coolant reservoir (→P. 358)
Engine oil filler cap (→ P. 356)
Power control unit coolant
reservoir ( →P. 358) Brake fluid reservoir
(→P. 360)
Fuse box ( →P. 384)
Washer fluid tank ( →P. 361)
Electric cooling fans
Condenser ( →P. 359)
Radiator (→ P. 359)1
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GS450h_OM_OM30G62U_(U)
6-3. Do-it-yourself maintenance
The coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir when the hybrid system is cold.
■Engine coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( →P. 461)
■Power control unit coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( →P. 461)
■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.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixt ure of 50% coolant and 50% deionized water.
(Minimum temperature: -31 °F [-35 °C])
Canada:
“Toyota Super Long Life Cool ant” is a mixture of 55% coolant and 45% deionized water.
(Minimum temperature: -44° F [-42°C])
For more details about coolant, contact your Lexus dealer.
■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 your Lexus de aler test the cap and check for leaks in the
cooling system.
Coolant
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GS450h_OM_OM30G62U_(U)
3596-3. Do-it-yourself maintenance
6
Maintenance and care
Check the radiator and condenser and clear away any foreign objects.
If either of the above parts is extremely dirty or you are not sure of their condi-
tion, have your vehicle inspected by your Lexus dealer.
WARNING
■When the hybrid system is hot
Do not remove the engine/power control un it coolant reservoir caps or the coolant
inlet cap. ( →P. 465)
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.
Radiator and condenser
WARNING
■When the hybrid system is hot
Do not touch the radiator or condenser as they may be hot and cause serious injuries,
such as burns.

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GS450h_OM_OM30G62U_(U)
7
When trouble arises
7-2. Steps to take in an emergency
If your vehicle overheats
●The needle of the engine coolant temperature gauge ( →P. 88) enters the red
zone or a loss of hybrid system power is experienced. (For example, the vehi-
cle 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. 410) 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 your Lexus
dealer.
The following may indicate that your vehicle is overheating.
Correction procedures
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4627-2. Steps to take in an emergency
GS450h_OM_OM30G62U_(U)
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. 464)
Water can be used in an emergency
if engine coolant is unavailable.
Start the hybrid system and turn the air conditioning system on to check
that the radiator cooling fans operate and to check for coolant leaks from
the radiator or hoses.
The fans operate when the air conditioning system is turned on immediately after a
cold start. Confirm that the fans are operating by checking the fan sound and air
flow. If it is difficult to check these, tu rn the air conditioning system on and off
repeatedly. (The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
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