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ES350 300h_OM_OM33A01U_(U)
6816-3. Do-it-yourself maintenance
6
Maintenance and care
The coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the engine 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. 8 1 3 , 8 1 6 )
■Power control unit coolant reservoir (hybrid vehicles)
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line. ( P. 8 1 6 )
Coolant
1
2
3
1
2
3
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ES350 300h_OM_OM33A01U_(U)
6-3. Do-it-yourself maintenance
■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 mixture of 50% coolant and 50% deionized
water. (Minimum temperature: -31 F [-35C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deionized
water. (Minimum temperature: -44 F [-42C])
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 dealer test the cap and check for leaks in
the cooling system.
CAUTION
■When the engine is hot
Do not remove the engine/power control unit coolant reservoir caps.
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 683 of 908
ES350 300h_OM_OM33A01U_(U)
6836-3. 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
condition, have your vehicle inspected by your Lexus dealer.
Radiator and condenser
CAUTION
■When the engine is hot
Do not touch the radiator or condenser as they may be hot and cause serious inju-
ries, such as burns.
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ES350 300h_OM_OM33A01U_(U)
6-3. Do-it-yourself maintenance
■Checking fluid level
The brake fluid level should be between the “MAX” and “MIN” lines on
the tank.
■Adding fluid
Make sure to check the fluid type and prepare the necessary item.
■Brake fluid can absorb moisture from the air
Excess moisture in the brake fluid can cause a dangerous loss of braking efficiency.
Use only newly opened brake fluid.
Brake fluid
Gasoline vehiclesHybrid vehicles
Fluid type FMVSS No.116 DOT 3 or SAE J1703 brake fluid
ItemsClean funnel
CAUTION
■When filling the reservoir
Take care as brake fluid can harm your hands and eyes and damage painted sur-
faces.
If fluid gets on your hands or in your ey es, flush the affected area with clean water
immediately.
If you still experience discomfort, see a doctor.
Page 685 of 908
ES350 300h_OM_OM33A01U_(U)
6856-3. Do-it-yourself maintenance
6
Maintenance and care
Check the 12-volt battery as follows.
■12-volt battery exterior
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
■Checking 12-volt battery fluid
Check that the level is between the “UPPER LEVEL” and “LOWER
LEVEL” lines.
“UPPER LEVEL” line
“LOWER LEVEL” line
If the fluid level is at or below the
“LOWER LEVEL” line, add distilled
water.
NOTICE
■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 out
or when the fluid level in the accumulator is high.
If the reservoir needs frequent refil ling, there may be a serious problem.
12-volt battery (gasoline vehicles)
1
2
1
2
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6-3. Do-it-yourself maintenance
■Adding distilled waterRemove the vent plug.
Add distilled water.
If the “UPPER LEVEL” line cannot
be seen, check the fluid level by
looking directly at the cell.
Put the vent plug back on and close it securely.
■Before recharging
When recharging, the 12-volt battery prod uces hydrogen gas which is flammable
and explosive. Therefore, observe the following before recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to disconnect
the ground cable.
●Make sure the “START STOP ENGINE” switch on the charger is off when con-
necting and disconnecting the charger cables to the 12-volt battery.
1
Low O.K.2
3
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ES350 300h_OM_OM33A01U_(U)
6876-3. Do-it-yourself maintenance
6
Maintenance and care
■After recharging/reconnecting the 12-volt battery
The engine 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 engine.
●Unlocking the doors using the smart access system with push-button start may not
be possible immediately after reconnecting the 12-volt battery. If this happens, use
the wireless remote control or the me chanical key to lock/unlock the doors.
●Start the engine with the “START STOP ENGINE” switch in ACCESSORY mode.
The engine may not start with the “START STOP ENGINE” switch turned off. How-
ever, the engine will operate normally from the second attempt.
●The “START STOP ENGINE” switch mode is recorded by the vehicle. If the 12-volt
battery is reconnected, the vehicle will return the “START STOP ENGINE” switch
mode to the status it was in before the 12-volt battery was disconnected. Make sure
to turn off the engine before disconnect the 12-volt battery. Take extra care when
connecting the 12-volt battery if the “START STOP ENGINE” switch mode prior to
discharge is unknown.
If the engine will not start even after mu ltiple attempts, contact your Lexus dealer.
CAUTION
■Chemicals in the 12-volt battery
Batteries contain poisonous and corrosive sulfuric acid and may produce hydro-
gen 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.
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2
3
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6-3. Do-it-yourself maintenance
CAUTION
■Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charge the 12-volt bat-
tery in a garage or closed room where there is insufficient ventilation.
■How to recharge the 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery may explode if
charged at a quicker rate.
■Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immediate medi-
cal 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 feel pain or burning, get medical atten-
tion immediately.
●If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the clothing and
follow the procedure above if necessary.
●If you accidentally swallow electrolyte
Drink a large quantity of water or milk . Get emergency medical attention imme-
diately.
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while th e engine is running. Also, be sure all
accessories are turned off.
■When adding distilled water
Avoid overfilling. Water spilled during 12-volt battery recharging may cause corro-
sion.