Lexus GS450h 2007 Using the hands-free system (for cellular phone) / LEXUS 2007 GS450H FROM JULY 2006 PROD. OWNER'S MANUAL (OM30A05U)

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Maintenance and care
CAUTION
■Chemicals in the 12 volt battery
A battery contains poisonous and corrosive sulfuric acid and may produce hydro-
gen gas which is flammable and explosive. To reduce the risk of death or serious
injury, take the following precautions while working on or near battery:
●Do not cause sparks by touching the battery terminals with tools.
●Do not smoke or light a match near the battery.
●Avoid contact with eyes, skin and clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when working near the battery.
●Keep children away from the battery.
■Where to safety charge the 12 volt battery
Always charge the battery in an open area. Do not charge the battery in a garage or
closed room where there is not sufficient ventilation.
■How to recharge the 12 volt battery
Only perform a slow charge (5A or less). The 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.
●If electrolyte gets on your skin 
Wash the affected area thoroughly. If you feel pain or a burning sensation, seek
medical attention 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. Fo llow with milk of magnesia, beaten raw
egg or vegetable oil. Get emergency medical attention immediately.

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Washer fluidIf any washer does not work or the
warning message appears on the
multi-information display, the
washer tank may be empty. Add
washer fluid.
NOTICE
■When recharging the 12 volt battery
Never recharge the battery while the hybrid system is on. Also, be sure all accesso-
ries are turned off.
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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Maintenance and care
Tires
Replace or rotate tires in accordance with maintenance schedule 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 tr ansmitters to detect low tire infla-
tion pressure before serious problems arise. ( P. 440, 445)
Front

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4-3. Do-it-yourself maintenance
Installing tire pressure warning valves and transmittersWhen replacing tires or wheels, tire pressure warning valves and trans-
mitters must also be installed.
When new tire pressure warning va lves 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 code registered by your Lexus dealer. ( P. 386)
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 or load weight, etc.
● When changing the tire size.
When the tire pressure warning sys tem is initialized, the current tire
inflation pressure is set as the pressure benchmark.

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Maintenance and care
■How to initialize the tire pressure warning system
Park the vehicle in safe place and turn the power switch to “OFF”
mode.
While the vehicle is moving, initialization is not performed.
Adjust the tire inflation pressure to the specified cold tire inflation
pressure level. ( P. 493)
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 power switch to “IG-ON” mode.
Push and hold the tire pressure
warning reset switch until the tire
pressure warning light blinks
slowly three times and the mes-
sage “PRESSURE INITIAL”
appears on the multi-information
display.
Wait for a few minutes with the “IG-ON” mode, and then turn
power switch to the “OFF” mode.
STEP1
STEP2
STEP3
STEP4
STEP5

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4-3. Do-it-yourself maintenance
Registering and selecting ID codes■ Registering ID codes
2 sets of tire pressure warning va lve and transmitter ID codes can be
registered. Once a second set of ti res 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 inst alled on the vehicle is registered.
“2nd” position: The ID code is not registered. When you replace a new
set of tires, purchase tire pressu re warning valves and transmitters
from your Lexus dealer and have the new ID code registered by your
Lexus dealer.
■ Selecting ID codes
When replacing tires, make sure to select the ID code set that matches
the new tire set. If the tire pressu re warning select switch is set to
wrong tire setting, the tire pressu re warning system will not operate
properly. After about 20 minutes, the tire pressure warning light
comes on after blinking for 1 minu te to indicate a system malfunction.
“MAIN”
“2nd”

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Maintenance and care
■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
fabric or bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or
location 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 warn ing valve and transmitter is not registered,
the tire pressure warning system will not work properly. After about 20 minutes, the
tire pressure warning light comes on after bl inking for 1 minute to indicate 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 used 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.
■Low profile tires (245/40R18, P245/40R18 and 245/40ZR18 tires)
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when co mpared to standard tires. Be sure to
use snow tires or snow chains on snowy and/or icy roads and drive carefully at a
speed appropriate for road and weather conditions.

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4-3. Do-it-yourself maintenance
■Maximum load of tire
Check that the maximum load of the replaced tire is greater than 1 /2 of the Gross
Axle Weight Ratings (GAWR) of either the front axle or the rear axle, whichever is
greater. 
As for the maximum load of the tire, see the load limit at maximum cold tire inflation
pressure mentioned on the sidewall of the tire, and as for the Gross Axle Weight
Ratings (GAWR), see the Certification Label. (
P. 393, 498).
■Tire types
1 Summer tires
Summer tires are high-speed performance tires best suited to highway driving
under dry conditions. Since summer tires do not have the same traction perfor-
mance as snow tires, summer tires are in adequate for driving on snow-covered
or icy roads. For driving on snow-covered roads or icy roads, the use of snow tires
is recommended. When installing snow tires, be sure to replace all four tires.
2 All season tires All season tires are designed to provide better traction in snow and to be ade-
quate for driving in most winter conditions , as well as for use year round. All sea-
son tires, however, do not have adequa te traction performance compared with
snow tires in heavy or loos e snow. Also, all season tires fall short in acceleration
and handling performance compared with summer tires in highway driving.
3Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires.
If you need snow tires, select tires of the same size, construction and load capac-
ity as the originally installed tires. Since your vehicle has radial tires as original
equipment, make sure your snow tires also have radial construction. Do not install
studded tires without first checking loca l regulations for possible restriction.
Snow tires should be installed on all wheels. ( P. 1 76 )
■Initializing the tire pressure warning system
Initialize the tires with the tire inflatio n pressure adjusted to the specified level.

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Maintenance and care
■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 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 warnin g reset switch, the tire pressure warn-
ing light does not flash 3 times and the setting message does not appear on the
multi-information display.
●After carrying out the initia lization procedure, the tire pressure warning light
blinks for 1 minute after driving for 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.

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■Tire pressure warning system certificationFor vehicles sold in the U.S.A.
NOTE:
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 th e FCC Rules. These limits are designed to
provide reasonable protection against harmful interference in a residential installa-
tion. This equipment generate s, 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.
●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
NOTE:
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.