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2-1. Driving procedures
RX400h_U
NOTICE
■When encountering flooded roads
Do not drive on a road that has flooded after heavy rain etc. Doing so may cause the
following serious damage to the vehicle.
●Engine stalling
●Short in electrical components
●Engine damage caused by water immersion
In the event that you drive on a flooded road and the vehicle is flooded, be sure to
have your Lexus dealer check the following.
●Brake function
●Changes in quantity and quality of oil and fluid used for the engine, transaxle, dif-
ferential, etc.
●Lubricant condition for the bearings and suspension joints (where possible) and
the function of all joints, bearings, etc.
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2-5. Driving information
RX400h_U
CAUTION
■Off-road driving precautions
Always observe the following precautions to minimize the risk of serious personal
injury or damage to your vehicle:
●Drive carefully when off the road. Do not take unnecessary risks by driving in
dangerous places.
●Do not grip the steering wheel spokes when driving off-road. A bad bump could
jerk the wheel and injure your hands. Keep both hands and especially your
thumbs on the outside of the rim.
●Always check your brakes for effectiveness immediately after driving in sand,
mud, water or snow.
●After driving through tall grass, mud, rock, sand, rivers, etc., check that there is no
grass, bush, paper, rags, stone, sand, etc. adhering or trapped on the underbody.
Clear off any such matter from the underbody. If the vehicle is used with these
materials trapped or adhering to the underbody, a breakdown or fire could occur.
●When driving off-road or in rugged terrain, do not drive at excessive speeds,
jump, make sharp turns, strike objects, etc. This may cause loss of control or vehi-
cle rollover causing death or serious injury. You are also risking expensive dam-
age to your vehicle’s suspension and chassis.
NOTICE
■To prevent the water damage
Take all necessary safety measures to ensure that water damage to the hybrid bat-
tery, hybrid system or other components does not occur.
●Water entering the engine compartment may cause severe damage to the hybrid
system. Water entering the interior may cause the hybrid battery stowed under
the rear seats to short circuit.
●Water entering the hybrid transaxle will cause deterioration in transmission qual-
ity. The malfunction indicator may come on, and the vehicle may not be drivable.
●Water can wash the grease from wheel bearings, causing rusting and premature
failure, and may also enter the transaxle case, reducing the gear oil’s lubricating
qualities.
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2-5. Driving information
RX400h_U
Winter driving tips
Carry out the necessary preparations and inspections before driving the
vehicle in winter. Always drive the vehicle in a manner appropriate to the
prevailing weather conditions.
■Pre-winter preparations
● Use fluids that are appropriate to the prevailing outside tempera-
tures.
• Engine oil
• Engine/power control unit coolant
• Washer fluid
• Have a service technician inspect the level and specific gravity
of battery electrolyte.
● Have the vehicle fitted with four snow tires or purchase a set of
tire chains for the front tires.
Ensure that all tires are the same size and brand, and that chains match
the size of the tires.
●Tire pressure falls in winter as the outside temperature falls. Add
2.9 to 4.3 psi (20 to 30 kPa, 0.2 to 0.3 kgf/cm2 or bar) to the
standard tire inflation pressure.
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4-2. Maintenance
4
Maintenance and care
RX400h_U
■Allow inspection and repairs to be performed by a Lexus dealer
●Lexus technicians are well-trained specialists and are kept up to date with the lat-
est service information. They are well informed about the operations of all sys-
tems on your vehicle.
●Keep a copy of the repair order. It proves that the maintenance that has been per-
formed is under warranty coverage. If any problem should arise while your vehi-
cle is under warranty, your Lexus dealer will promptly take care of it.
CAUTION
■Warning in handling of battery
●Engine exhaust, some of its constituents, and a wide variety of automobile com-
ponents contain or emit chemicals known to the State of California to cause can-
cer and birth defects and other reproductive harm. Work in a well ventilated area.
●Oils, fuels and fluids contained in vehicles as well as waste produced by compo-
nent wear contain or emit chemicals known to the State of California to cause
cancer and birth defects or other reproductive harm. Avoid exposure and wash
any affected area immediately.
●Battery posts, terminals and related accessories contain lead and lead com-
pounds which are known to cause brain damage. Wash your hands after han-
dling. (→P. 3 2 7 )
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4-2. Maintenance
RX400h_U
General maintenance
Engine compartment
ItemsCheck points
12-volt batteryMaintenance-free. (→P. 3 2 7 )
Brake fluidAt the correct level? ( →P. 3 2 5 )
Engine/power control unit coolantAt the correct level? ( →P. 3 2 3 )
Engine oilAt the correct level? ( →P. 3 1 8 )
Exhaust systemNo fumes or strange sounds?
Radiator/condenser/hosesNot blocked with foreign matter?
(→ P. 3 2 5 )
Wa s h e r f l u i dAt the correct level? ( →P. 3 2 9 )
Listed below are the general maintenance items that should be performed
at the intervals specified in the “Warranty and Services Guide” or
“Owner’s Manual Supplement”. It is recommended that any problem you
notice should be brought to the attent ion of your Lexus dealer or qualified
service shop for advice.
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4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_U
ItemsParts and tools
Engine oil level (→P. 3 1 8 )
• “Toyota Genuine Motor Oil” or
equivalent
• Rag or paper towel, funnel (used
only for adding engine oil)
Fuses (→ P. 3 5 2 )• Fuse with same amperage rating as
original
Headlight aim ( →P. 364)• Phillips-head screwdriver
Radiator and condenser (→P. 3 2 5 )
Tire inflation pressure ( →P. 3 4 0 )• Tire pressure gauge
• Compressed air source
Wa s h e r f l u i d ( →P. 3 2 9 )
• Water washer fluid containing anti-
freeze (for winter use)
•Funnel
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4-3. Do-it-yourself maintenance
RX400h_U
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:
■When working on the engine compartment
●Keep hands, clothing, and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, inverter, 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 or rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel
and battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and
corrosive sulfuric acid.
●Never touch, disassemble, remove or replace the high voltage parts, cables and
their connectors. It can cause severe burns or electric shock that may result in
death or serious injury.
●When the hybrid system is operating with the READY light on, the engine may
suddenly start in some cases. When you inspect the engine compartment, be
sure to turn off the hybrid system.
■When working near the electric cooling fan or radiator grille
Be sure the engine switch is off.
With the engine switch on, the electric cooling fan may automatically start to run if
the air conditioning is on and/or the coolant temperature is high. (→P. 3 2 5 )
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting
in the eyes.
NOTICE
■If you remove the air cleaner:
Driving with the air filter removed may cause excessive engine wear due to dirt in
the air. Also a backfire could cause a fire in the engine compartment.
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4-3. Do-it-yourself maintenance
RX400h_U
Engine compartment
Brake fluid reservoir(→P. 325)
Engine oil level dipstick (→P. 318)
Engine oil filler cap (→P. 318)
Power control unit coolant
reservoir ( →P. 323)
Fuse boxes ( →P. 352)Engine coolant radiator
(→P. 325)
Condenser ( →P. 325)
Power control unit coolant
radiator ( →P. 325)
Electric cooling fans
Engine coolant reservoir (→P. 323)
12-volt battery ( →P. 327)
Washer fluid tank (→P. 329)