2008 LEXUS RX400H Owners Manual

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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.

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CAUTION
■When refilling washer fluid
Do not refill washer fluid when the hybrid system is hot or operating, as the washer
fluid contains alcohol and may catch fire if spilled on the engine etc.
NOTICE
■Do not use any fluid other than washer fluid
Do not use soapy water or engine antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle’s painted surfaces.
■Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures listed on the washer fluid tank.

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Tires
Replace or rotate tires in accordance with maintenance schedules and
treadwear.
■Checking tires
New tread
Treadwear indicator
Worn tread
The location of treadwear indi-
cators is shown by the “TWI” or
“∆ ” marks, etc., molded on the
sidewall of each tire.
Check spare tire condition and
inflation pressure if not rotated.
■ Tire rotation
Rotate the tires in the order
shown.
To equalize tire wear and extend
tire life, Lexus recommends that
tire rotation is carried out at the
same interval as tire inspection.
■The tire pressure warning system
Your Lexus is equipped with a tire pressure warning system that uses
tire pressure warning valves and transmitters to detect low tire infla-
tion pressure before serious problems arise. ( →P. 391, 398)
Front

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Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and trans-
mitters must also be installed.
When new tire pressure warning valves and transmitters are installed,
new tire pressure warning valve and transmitter ID codes must be regis-
tered in the tire pressure warning computer and tire pressure warning
system must be initialized. Have tire pressure warning valve and transmit-
ter ID codes registered by your Lexus dealer. ( →P. 3 3 4 )
Initializing the tire pressure warning system
■ The tire pressure warning system must be initialized in the following
circumstances:
● When changing the tire inflation pressure by changing traveling
speed.
● When changing the tire size.
When the tire pressure warning system is initialized, the current tire
inflation pressure is set as the pressure benchmark.

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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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Registering and selecting ID codes■ Registering ID codes
2 sets of tire pressure warning valve and transmitter ID codes can be
registered. Once a second set of tires is registered at “2nd”, you can
switch between tire set settings simply by pressing the tire pressure
warning select switch.
There are 2 settings:
“MAIN” position: The ID code of the tire pressure warning valve and
transmitter on the tires originally installed on the vehicle is registered.
“2nd” position: The ID code is not registered. When you replace a new
set of tires, purchase tire pressure warning valves and transmitters
from your Lexus dealer and have the new ID code registered by your
Lexus dealer.