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Maintenance and care
GS450h_300h_OM_OM30F92E_(EE) The coolant level is satisfactory if it is between the “FULL”/“F” and “LOW”/“L”
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” lin e, add coolant up to the “FULL” line.
( P. 535)
■Power control unit coolant reservoir
Coolant
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GS450hGS300h
GS450hGS300h
Reservoir cap
“FULL” line
“LOW” line Reservoir cap
“F” line
“L” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”line. ( P. 535) If the level is on
or below the “L” line,
add coolant up to the “F” line. ( P. 535)
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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.
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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.
Page 412 of 600
4126-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
12-volt battery
The 12-volt battery is located on the
left-hand side of trunk.
Pull the strap upwards to lift up the 12-
volt battery cover.
Make sure that the 12-volt battery terminals are not corroded and that there are
no loose connections, cracks, or loose clamps. Terminals
Hold-down clamp
Location
Removing the 12-volt battery cover
Exterior
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Maintenance and care
GS450h_300h_OM_OM30F92E_(EE) The meanings of each caution symbol on the top of the 12-volt battery are as fol-
lows:
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flammable and
explosive. Therefore, observe the following precautions before recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to disconnect the
ground cable.
●Make sure the power switch on the charger is off when connecting and disconnecting
the charger cables to the 12-volt battery.
■After recharging/reconnecting the 12-volt battery
●The hybrid system may not start. Follow the procedure below to initialize the system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the hybrid system.
●Unlocking the doors using the smart entry & start system may not be possible immedi-
ately after reconnecting the 12-volt battery. If this happens, use the wireless remote
control or the mechanical key to lock/unlock the doors.
●Start the hybrid system with the power switch in ACCESSORY mode. The hybrid sys-
tem may not start with the power switch turned off. However, the hybrid system will
operate normally from the second attempt.
●The power switch mode is recorded by the vehicle. If the 12-volt battery is reconnected,
the vehicle will return the power switch mode to the status it was in before the 12-volt
battery was disconnected. Make sure to tu rn off the power switch before disconnect
the 12-volt battery. Take extra care when connecting the 12-volt battery if the power
switch mode prior to discharge is unknown.
If the system will not start even after multiple attempts at all methods above, contact any
authorized Lexus retailer or Lexus author ized repairer, or any reliable repairer.
Caution symbols
No smoking, no naked
flames, no sparks12-volt battery acid
Shield eyesNote operating instructions
Keep away from childrenExplosive gas
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4146-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may produce
hydrogen gas which is flammable and explosive. To reduce the risk of death or serious
injury, take the following precautions while working on or near the 12-volt battery:
●Do not cause sparks by touching the 12-volt battery terminals with tools.
●Do not smoke or light a match near the 12-volt battery.
●Avoid contact with eyes, skin and clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when working near the 12-volt battery.
●Keep children away from the 12-volt battery.
■Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charge the 12-volt battery in
a garage or closed room where th ere is insufficient ventilation.
■How to recharge the 12-volt battery
Recharge at a current of 5 A or less and make sure that the recharging period does not
exceed a total of 12 hours.
■Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immediate medical
attention. If possible, continue to apply water with a sponge or cloth while traveling to
the nearest medical facility.
●If electrolyte gets on your skin
Wash the affected area thoroughly. If you f eel pain or burning, get medical attention
immediately.
●If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the clothing and fol-
low the procedure above if necessary.
●If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medical attention immedi-
ately.
■When replacing the 12-volt battery
Use a 12-volt battery designed for this vehicle. Failure to do so may cause gas (hydro-
gen) to enter the passenger compartment, causing a fire or explosion.
For replacement of the 12-volt battery, contact any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
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Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is operating. Also, be sure
all accessories are turned off.
Page 416 of 600
4166-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
Tires
Check if the treadwear indicators are show ing on the tires. Also check the tires
for uneven wear, such as excessive wear on one side of the tread.
Check the spare tire condition and pressure if not rotated.
New tread
Worn tread
Treadwear indicator
The location of treadwear indicators is shown by the “TWI” or “ ” mark, etc., molded
into the sidewall of each tire.
Replace the tires if the treadwear indicators are showing on a tire.
Replace or rotate tires in accordance with maintenance schedules and trea d-
wear.
Checking tires
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