2019 LEXUS GS300H radiator

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6-3. Do-it-yourself maintenance
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
Do-it-yourself service precautions
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
condition ( P. 412)
•Grease
• Conventional wrench (for terminal clamp bolts)
Engine/power
control unit coolant level ( P. 409)
•“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 pre-mixed with 50%
coolant and 50% deionized water.
• Funnel (used only for adding coolant)
Engine oil level ( P. 406)
• “Toyota Genuine Motor Oil” or equivalent
•Rag or paper towel
• Funnel (used only for adding engine oil)
Fuses (P. 437)• Fuse with same amperage rating as original
Light bulbs ( P. 442)
• Bulb with same number and wattage rating as original
• Phillips-head screwdriver• Flathead screwdriver
•Wrench
Radiator and condenser ( P. 411)
Tire inflation
pressure ( P. 429)• Tire pressure gauge• Compressed air source
Washer fluid
( P. 411)
• Water or washer fluid containing antifreeze (for winter use)
• Funnel (used only for adding water or washer fluid)

4006-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
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 enginecompartment.
●Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flamma-
ble.
●Take care because brake fluid can harm your hands or eyes and damage painted sur- faces. If fluid gets on your hands or in your eyes, flush the affected area with clean
water immediately. If you still experi ence discomfort, consult a doctor.
■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. 411)
■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 filter removed may cause excessive engine wear due to dirt in the air.
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads wear or when the fluid level in the accumulator is high.
If the reservoir needs frequent refillin g, it may indicate a serious problem.

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6-3. Do-it-yourself maintenance
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
Engine compartment
GS450h
■12-volt battery
 P. 412
Engine oil level dipstick
( P. 406)
Engine coolant reservoir
( P. 409)
Engine oil filler cap ( P. 407)
Power control unit coolant
reservoir ( P. 409)
Fuse box ( P. 437)
Washer fluid tank ( P. 411)
Electric cooling fans
Condenser ( P. 411)
Radiator ( P. 411)
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4046-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
GS300h
■12-volt battery
 P. 412
Power control unit coolant
reservoir ( P. 409)
Engine oil level dipstick
( P. 406)
Engine oil filler cap ( P. 407)
Engine coolant reservoir
( P. 409)
Fuse box ( P. 437)
Washer fluid tank ( P. 411)
Electric cooling fans
Condenser ( P. 411)
Radiator ( P. 411)
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4106-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(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 mixt ure of 50% coolant and 50% deionized water. (Minimum temperature: -35 C [-31F])
For more details about coolant, contact an y authorized Lexus retailer or Lexus autho-
rized repairer, or any reliable repairer.
■If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/p ower control unit coolant reservoir caps,
drain cock and water pump. If you cannot find a leak, have any authorized Lexus retailer or Lexus authorized repairer, or any reliable repairer, test the cap an d check for leaks in the cooling system.
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. 540) 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.

411 6-3. Do-it-yourself maintenance
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Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
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 any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
If any washer does not work or the
warning message appears on the multi-
information display, the washer tank
may be empty. Add washer fluid.
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.
Washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the hybrid sy stem is hot or operating as washer fluid contains alcohol and may catch fi re if spilled on the engine etc.
NOTICE
■Do not use any fluid other than washer fluid
Do not use soapy water or engine antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle’s painted surfaces.
■Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures listed on the label of the washer fluid bottle.

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7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30F92E_(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. 466) 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 retailer or Lexus authorized repairer, or any reli-able repairer.
The following may indicate that your vehicle is overheating.
Correction procedures
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5377-2. Steps to take in an emergency
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When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
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 op erating 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 any authorized Lexus
retailer or Lexus authorized repairer, or any reliable repairer.
If the fans are operating:
Have the vehicle inspected at the nearest any authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer.
■If “Hybrid System Overheated Reduced Output Power” is shown on the
multi-information display
Stop the vehicle in a safe place.
Stop the hybrid system and carefully lift the hood.
After the hybrid system has cooled down, inspect the hoses and radiator
core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immediately contact any autho-
rized Lexus retailer or Lexus authorized repairer, or any reli-able repairer.
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