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RX400h_UExample of follow-up cruising (when following a vehicle driving slower
than the set speed):
When the speed is set to 62 mph (100 km/h) and the vehicle ahead is
driving at 50 mph (80 km/h)
The system continues follow-up cruising while adjusting for changes in the
speed of the vehicle ahead in order to maintain the vehicle-to-vehicle dis-
tance set by the driver.
Example of acceleration (when there are no longer vehicles driving
slower than the set speed in the lane ahead):
When the speed is set to 62 mph (100 km/h) and the vehicle ahead
driving at 50 mph (80 km/h) is out of the lane
When the vehicle ahead of you executes a lane change, the system slowly
accelerates until the set vehicle speed is reached. The system then returns to
fixed speed cruising.
■Fine adjustment of the set speed
Adjustment of the set speed by the following speed can be made by lightly pressing
the lever up or down and releasing it.
In the constant speed control mode: Approximately 1.0 mph (1.6 km/h)
In the vehicle-to-vehicle distance control mode: U.S.A.: Approximately 5 mph (8 km/h)
Canada: Approximately 3 mph (5 km/h)
■Dynamic laser cruise control warning lights, display and buzzers
Warning lights, display and buzzers are used to indicate a system malfunction or to
alert you to the need for caution while driving. ( →P. 3 9 8 )
■The dynamic laser cruise can be set when
●The shift lever is in D.
●Vehicle speed is between approximately 27 mph (45 km/h) and 85 mph (135
km/h).
■Accelerating
The vehicle can be accelerated normally.
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CAUTION
■When the slip indicator flashes and a warning buzzer sounds
This situation occurs immediately while VSC is activated. Always drive carefully.
Reckless driving may cause an accident. Exercise particular care when the indica-
tor light flashes and a buzzer sounds.
■Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
pressure level.
The ABS and VSC systems will not function correctly if different tires are fitted on
the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will affect the
VDIM, and may cause the system to malfunction.
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Maintenance and care
RX400h_U
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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Maintenance and care
RX400h_U
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.
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Maintenance and care
RX400h_U■
How to initialize the tire pressure warning system
Park the vehicle in safe place and turn off the hybrid system.
While the vehicle is moving, initialization is not performed.
Adjust the tire inflation pressure to the specified cold tire inflation
pressure level. (→ P. 4 3 9 )
Make sure to adjust the tire pressure to the specified cold tire inflation
pressure level. The tire pressure warning system will operate based on
this pressure level.
Turn the engine switch to the ON position.
Push and hold the tire pressure
warning reset switch until the tire
pressure warning light blinks
slowly three times.
Wait for a few minutes with the engine switch is in the ON posi-
tion, and then turn the engine switch to the OFF position.
STEP1
STEP2
STEP3
STEP4
STEP5
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Maintenance and care
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Selecting ID codes
When replacing tires, make sure to select the ID code set that matches
the new tire set. If the tire pressure select switch is set to the wrong tire
setting, the tire pressure warning system will not operate properly.
After driving for about 20 minutes, the tire pressure warning light
comes on after blinking for 1 minute to indicate a system malfunction.
“MAIN”
“2nd”
■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits, cracks deep enough to expose the fab-
ric or bulges indicating internal damage.
●A tire goes flat repeatedly or cannot be properly repaired due to the size or loca-
tion of a cut or other damage.
If you are not sure, consult with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered,
the tire pressure warning system will not work properly. After driving for about 20
minutes, the tire pressure warning light comes on after blinking for 1 minute to indi-
cate a system malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if they
have seldom or never been us ed or damage is not obvious.
■If the tread wears down below 0. 16 in. (4 mm) on snow tires
The effectiveness of snow tires is lost.
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■If you push the tire pressure warning reset switch accidentally
If initialization is performed, adjust the tire inflation pressure to the specified level
and initialize the tire pressure warning system again.
■When the initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following cases,
the settings have not been recorded and the system will not operate properly. If
repeated attempts to record tire inflation pressure settings are unsuccessful, have
the vehicle inspected by your Lexus dealer.
●When operating the tire pressure warning reset switch, the tire pressure warning
light does not flash 3 times.
●After carrying out the initialization procedure, the tire pressure warning light
blinks for 1 minute then stays on after driving for about 20 minutes.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.
■Tire pressure warning system certificationFor vehicles sold in the U.S.A.
This device complies with Part 15 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) this device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
NOTICE:
This equipment has been tested and found to comply with the limits for a Class B
digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference in a residential installa-
tion. This equipment generates, uses and can radiate radio frequency energy and, if
not installed and used in accordance with the instructions, may cause harmful inter-
ference to radio communications. However, there is no guarantee that interference
will not occur in a particular installation. If this equipment does cause harmful inter-
ference to radio or television reception, which can be determined by turning the
equipment off and on, the user is encouraged to try to correct the interference by
one or more of the following measures:
●Reorient or relocate the receiving antenna.
●Increase the separation between the equipment and receiver.
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●Connect the equipment into an outlet on a circuit different from that to which the
receiver is connected.
●Consult the dealer or an experienced radio/TV technician for help.
FCC WARNING:
Changes or modifications not expressly approved by the party responsible for
compliance could void the user's authority to operate the equipment. For vehicles sold in Canada
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must accept any interference, including interfer-
ence that may cause undesired operation of the device.
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train, as well as dangerous
handling characteristics, which may lead to fatal or injury accidents.
●Do not mix tires of different makes, models, tread patterns or treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix radial, bias-belted, or bias-ply tires.
●Do not mix summer, all season and winter tires.
■When initializing the tire pressure warning system
Do not push the tire pressure warning reset switch without first adjusting the tire
inflation pressure to the specified level. Otherwise, the tire pressure warning light
may not come on even if the tire inflation pressure is low, or it may come on when
the tire inflation pressure is actually normal.