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CAUTION
■Used engine oil
●Used engine oil contains potentially harmful contaminants which may cause skin
disorders such as inflammation or skin cancer, so care should be taken to avoid
prolonged and repeated contact. To remove used engine oil from your skin, wash
thoroughly with soap and water.
●Dispose of used oil and filters only in a safe and acceptable manner. Do not dis-
pose of used oil and filters in household trash, in sewers or onto the ground.
Call your Lexus dealer, service station or auto parts store for information con-
cerning recycling or disposal.
●Do not leave used engine oil within the reach of children.
NOTICE
■To prevent serious engine damage:
Check the oil level on regular basis.
■When replacing the engine oil
●Be careful not to spill engine oil on the vehicle components.
●Avoid overfilling, or the engine could be damaged.
●Check the oil level on the dipstick every time you refill the vehicle.
●Be sure the engine oil filler cap is properly tightened.
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CoolantThe 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 Reser voir cap
Full (upper line)
Low (lower line)
If the level is on or below the LOW
line, add coolant up to the FULL
line.
Power control unit coolant reservoir
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■If the coolant level drops within a short time after replenishing
Visually check the radiator, hoses, reservoir cap, radiator cap, drain cock and water
pump.
If you cannot find a leak, have your Lexus dealer pressure test the cap and check for
leaks in the cooling system.
■Coolant selection
Only use Toyota Super Long Life Coolant or 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. (Enabled: -31 °F [-35 °C])
Canada: Toyota Super Long Life Coolant is a mixture of 55% coolant and 45% deionized water. (Enabled: -44 °F [-42 °C])
For more details about coolant, contact your Lexus dealer.
CAUTION
■When the coolant may be hot
Do not remove the radiator cap.
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing burns or other injuries.
NOTICE
■When adding the coolant
Coolant is neither plain water not 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 damaging parts or paint.
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Radiator and condenserCheck the radiator and condenser and clear any foreign objects.
If either of the above parts are extremely dirty or you are not sure of their
condition, have your vehicle checked by your Lexus dealer.
Brake fluid■ Checking fluid level
The brake fluid level should be between the MAX and MIN lines on
the tank.
MAX
MIN
If the level is low, take your vehicle
to a Lexus dealer as soon as possi-
ble. Do not drive your vehicle if the
red brake system warning light is
on. Call a Lexus dealer for assis-
tance.
Make sure to check the fluid type.
CAUTION
■When the engine is hot
Do not touch the radiator or condenser, as they may be hot and you may be burned.
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■Brake fluid can absorb moisture from the air
Excess moisture in the fluid can cause a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
CAUTION
■When filling the reservoir
Take care because brake fluid can harm your hands or eyes and damage painted
surfaces.
If fluid gets in your eyes, flush your eyes with clean water immediately.
If you still experience discomfort, see a doctor.
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 or
when the fluid level in the accumulator is high.
If the reservoir needs frequent refilling, it may indicate a serious problem.
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12-volt batteryCheck 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.
Te r m i n a l s
Hold-down clamp
■ Checking the 12-volt battery condition
Check the 12-volt battery condition using the indicator color.
Blue: Good condition
White: Charging is necessary.
Have the vehicle inspected by
your Lexus dealer.
Red: Not working properly,
have the 12-volt battery
checked by your Lexus dealer.
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flammable
and explosive. Therefore, before recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to discon-
nect 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.
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■After recharging/reconnecting the 12-volt battery
In some cases, the hybrid system may not start. If this happens, follow the procedure
below. (If the system does not start first time, repeat the procedure.)
Turn the hybrid system off. Open and close the driver's door, and turn the hybrid
system on.
If the system will not start even after repeating the procedure, contact your Lexus
dealer.
CAUTION
■Chemicals in the 12-volt battery:
The 12-volt battery contains poisonous and corrosive sulfuric acid and may pro-
duce 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 safety 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 not sufficient 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.
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Washer fluidIf any washer does not work or the
low washer fluid warning light
comes on, the washer tank may be
empty. Add washer fluid.
CAUTION
■Emergency measures regarding electrolyte
●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. Follow with milk of magnesia, beaten raw
egg or vegetable oil. Get emergency medical attention immediately.
■When replacing the 12-volt battery
Use a 12-volt battery designed for the RX400h. Failure to do so may cause gas
(hydrogen) to enter the passenger compartment, causing a fire or explosion.
For replacement of the 12-volt battery, contact your Lexus dealer.
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is running. Also, be sure
all accessories are turned off.