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7-3. Do-it-yourself maintenance
7
Maintenance and care
Do-it-yourself service precautions
If you perform maintenance by yourself, be sure to follow the correct
procedure as given in these sections.
ItemsPa r t s a n d t o o l s
12-volt battery condition
(gasoline vehicles) (P. 5 5 7 )
•Warm water
•Baking soda
•Grease
• Conventional wrench
(for terminal clamp bolts)
•Distilled water
12-volt battery condition
(hybrid vehicles) ( P. 5 6 2 )•Grease
• Conventional wrench (for terminal
clamp bolts)
Brake fluid level ( P. 5 5 6 )
• FMVSS No.116 DOT 3 or SAE J1703
brake fluid
•Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine coolant level
(gasoline vehicles) ( P. 5 5 3 )
• “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 technol-
ogy
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 Coolant” is
pre-mixed with 55% coolant and
45% deionized water.
• Funnel (used only for adding coolant)
Engine/power control unit coolant level
(hybrid vehicles) ( P. 5 5 3 )
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5397-3. Do-it-yourself maintenance
7
Maintenance and care
CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious
injury, observe the following precautions.
■When working on the engine compartment
●Hybrid vehicles: Make sure that the “POWER ON” on the multi-information dis-
play and the “READY” indicator are both off.
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Gasoline vehicles: Be careful not to touc h the engine, radiator, exhaust manifold,
etc. right after driving as they may be hot. Oil and ot her fluids may also be hot.
●Hybrid vehicles: Be careful not to touch the engine, power control 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.
●Gasoline vehicles: Do not smoke, cause sparks or expose an open flame to fuel
or the 12-volt battery. Fuel and 12-volt battery fumes are flammable.
●Hybrid vehicles: Do not smoke, cause sparks or expose an open flame to fuel.
Fuel fumes are flammable.
●Gasoline vehicles: Be extremely cautious when working on the 12-volt battery. It
contains poisonous and corrosive sulfuric acid.
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7-3. Do-it-yourself maintenance
7
Maintenance and care
Engine compartment
Gasoline vehicles (2GR-FE engine)
Washer fluid tank (P. 561)
Engine oil filler cap (P. 550)
Engine oil level dipstick (P. 548)
Engine coolant reservoir (P. 553) Brake fluid reservoir
(P. 5 5 6 )
Fuse box ( P. 586)
12-volt battery ( P. 5 5 7 )
Electric cooling fans
Condenser ( P. 555)
Radiator ( P. 555)1
2
3
4
5
6
7
8
9
10
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7-3. Do-it-yourself maintenance
Hybrid vehicles (2AR-FXE engine)
■12-volt battery (hybrid vehicles)
P. 5 6 2
Washer fluid tank ( P. 561)
Fuse boxes ( P. 586)
Power control unit coolant
reservoir ( P. 553)
Engine oil level dipstick (P. 548)
Engine oil filler cap (P. 550) Engine coolant reservoir
(P. 553)
Brake fluid reservoir (P. 5 5 6 )
Power control unit coolant
radiator ( P. 555)
Electric cooling fans
Condenser ( P. 555)
Engine coolant radiator (P. 555)1
2
3
4
5
6
7
8
9
10
11
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ES350_300h_OM_OM33B99U_(U)
5577-3. Do-it-yourself maintenance
7
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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7-3. 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 power switch on the charger is off when connecting and discon-
necting the charger cables to the 12-volt battery.
1
Low O.K.2
3
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5597-3. Do-it-yourself maintenance
7
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.
1
2
3
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7-3. 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.