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130
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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306
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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318
4-3. Do-it-yourself maintenance
RX400h_U■
Installing the clips
Open
Insert
Press
Engine oil
With the engine at operating temperature and turned off, check the oil
level on the dipstick.
■ Checking the engine oil
Park the vehicle on level ground. After turning off the hybrid sys-
tem, wait more than five minutes for the oil to drain back into the
bottom of the engine.
Hold a rag under the end and pull
the dipstick out.
Wipe the dipstick clean.
Reinsert the dipstick fully.
Holding a rag under the end, pull the dipstick out and check the
oil level.
STEP1
STEP2
STEP3
STEP4
STEP5
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319
4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_UWipe the dipstick and reinsert it fully.
Low
Full
■ Adding engine oil
If the oil level is below or near the
low level mark, add engine oil of
the same type as already in the
engine.
Make sure to check the oil type and prepare the items needed before
adding oil. Remove the oil filler cap.
Add engine oil slowly, checking the dipstick.
Install the filler cap, turning it clockwise.
It takes about 1.6 qt. (1.5 L, 1.3 lmp. qt.) to raise the oil level from low to full on the
dipstick.
STEP6
Oil gradeILSAC multi-grade engine oil
ItemsClean funnel
STEP1
STEP2
STEP3
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4-3. Do-it-yourself maintenance
RX400h_U
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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5
When trouble arises
393
5-2. Steps to take in an emergency
RX400h_U
■Key reminder buzzer
The buzzer indicates that the key has not been removed from the engine switch
(with the engine switch in the ACC or LOCK position and the driver’s door
opened).
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is your vehicle low on gas?
If it is, refuel the vehicle immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The lamp will go off after taking several driving trips.
If the light does not go off even after several trips, contact your Lexus dealer as soon
as possible.
■Front passenger detection sensor and passenger seat belt reminder
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash, even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■Changing the engine oil (U.S.A. only)
Make sure to reset the oil change system. ( →P. 3 2 1 )
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pushing the tire
pressure warning reset switch does not turn off the tire pressure warning light.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).
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5-2. Steps to take in an emergency
RX400h_U
Wa r n i n g m e s s a g eDetailsCorrection procedure
(U.S.A. only)
Indicates that the engine
oil is scheduled to be
changed.
Check the engine oil, and
change if necessary.
Comes on approximately
4500 miles (7200 km)
after the engine oil is
changed. (The indicator
will not work properly
unless the oil mainte-
nance data has been
reset.)
(U.S.A. only)
Indicates that the engine
oil should be changed.
Check and change the
engine oil.
Comes on approximately
5000 miles (8000 km)
after the engine oil is
changed (and the oil
maintenance data has
been reset).