Page 416 of 1014
4054-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and
total load capacity. In addition, make sure that the tires are inflated to the
recommended tire inflation pressure level.
The ABS, TRC and VSC systems will not function correctly if different
tires are installed on the vehicle.
Contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional for further information when replacing tires or
wheels.
Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspension will
affect the driving assist systems, and may cause a system to malfunction.
Page 450 of 1014

4334-6. Driving tips
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
the accelerator and gently apply the brakes. A greater amount of
electrical energy can be retained when slowing down.
Air conditioning
Use the air conditioning only when necessary. Doing so can help
control excessive gasoline consumption.
In summer: In high temperatures, use the recirculated air mode.
Doing so will help to reduce the burden on the air conditioner
and reduce fuel consumption as well.
In winter: Because the gasoline engine will not automatically cut
out until the gasoline engine and the interior of the vehicle are
warm, it will consume fuel. Also, fuel consumption can be
improved by avoiding overuse of the heater.
Checking tire inflation pressure
Make sure to check the tire inflation pressure frequently.
Improper tire inflation pressure can cause poor fuel consumption.
Also, as snow tires can cause large amounts of friction, their use
on dry roads can lead to poor fuel consumption. Use a tire that is
appropriate for the season.
Luggage
Carrying heavy luggage can lead to poor fuel consumption.
Avoid carrying unnecessary luggage. Installing a large roof rack
can also cause poor fuel consumption.
Warming up before driving
Since the gasoline engine starts up and cuts out automatically
when cold, warming up the engine is unnecessary. Moreover, fre-
quently driving short distances will cause the engine to repeat-
edly warm up, which can lead to poor fuel consumption.
Page 743 of 1014
719
6Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)6-1. Maintenance and care
Cleaning and protecting
the vehicle exterior ......... 720
Cleaning and protecting
the vehicle interior .......... 724
6-2. Maintenance
Maintenance
requirements ................... 728
6-3. Do-it-yourself maintenance
Do-it-yourself service
precautions...................... 731
Hood ................................. 734
Positioning a floor jack ..... 735
Engine compartment ......... 737
12-volt battery................... 748
Tires .................................. 753
Tire inflation pressure ....... 770
Wheels .............................. 772
Air conditioning filter ....... 775
Electronic key battery ....... 777
Checking and replacing
fuses ................................ 780
Light bulbs ........................ 800
Page 756 of 1014

7326-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Light bulbs (P. 803)
• Bulb with same number and watt-
age rating as original
• Phillips-head screwdriver
• Flathead screwdriver
•Wrench
Radiator and condenser (P. 747)
Tire inflation pressure (P. 772)• Tire pressure gauge
• Compressed air source
Wa s h e r f l u i d (P. 748)
• Water or washer fluid containing
antifreeze (for winter use)
• Funnel (used only for adding
water or washer fluid)
CAUTION
The engine compartment contains many mechanisms and fluids that may
move suddenly, become hot, or become electrically energized. To avoid death
or serious injury, observe the following precautions.
When working on the engine compartment
Make sure that the “POWER ON” on the multi-information display and
the “READY” indicator are both off.
Keep hands, clothing and tools away from the moving fan and engine
drive belt.
Be careful not to touch the engine, power control unit, 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 and rags, in the
engine compartment.
Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes
are flammable.
Take care because brake fluid can harm your hands or eyes and damage
painted surfaces. If fluid gets on your hands or in your eyes, flush the
affected area with clean water immediately. If you still experience dis-
comfort, consult a doctor.
ItemsParts and tools
Page 780 of 1014

7566-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Your vehicle is equipped with a tire pressure warning system that
uses tire pressure warning valves and transmitters to detect low tire
inflation pressure before serious problems arise.
Vehicles without the tire inflation pressure display function
If the tire pressure drops below a predetermined level, the driver is
warned by a warning light. (P. 834)
Vehicles with the tire inflation pressure display function
If the tire pressure drops below a predetermined level, the driver
is warned by a screen display and a warning light. (P. 859)
The tire pressure detected by the tire pressure warning system
can be displayed on the multi-information display. (P. 117)
Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and
transmitters must also be installed.
When new tire pressure warning valves and transmitters are
installed, new ID codes must be registered in the tire pressure
warning computer and the tire pressure warning system must be
initialized. Have tire pressure warning valve and transmitter ID
codes registered by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional. (P. 758)
Tire pressure warning system (if equipped)
Page 781 of 1014
757 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
Initializing the tire pressure warning system
The tire pressure warning system must be initialized in the fol-
lowing circumstances:
When rotating the tires.
When the tire inflation pressure is changed such as when
changing traveling speed.
When the tire pressure warning system is initialized, the current
tire inflation pressure is set as the benchmark pressure.
How to initialize the tire pressure warning system
Park the vehicle in a safe place and turn the power switch off.
Initialization cannot be performed while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire infla-
tion pressure level. (P. 936)
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 ON mode.
1
2
3
Page 783 of 1014

759 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
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, and 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 any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Replacing tires and wheels (vehicles with the tire pressure warning system)
If the ID code of the tire pressure warning valve and transmitter is not regis-
tered, the tire pressure warning system will not work properly. After driving
for about 10 minutes, the tire pressure warning light blinks for 1 minute and
stays on to indicate a system malfunction.
Tire life
Any tire over 6 years old must be checked by a qualified technician even if it
has seldom or never been used or damage is not obvious.
Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pres-
sure checks. Make sure to check tire inflation pressure as part of your routine
of daily vehicle checks.
When rotating the tires (vehicles with the tire pressure warning system featur-
ing a tire inflation pressure display function)
Make sure that the power switch is off. If the tires are rotated while the power
switch is in ON mode, the tire position information will not be updated.
If this accidentally occurs, either turn the power switch to off and then to ON
mode, or initialize the system after checking that the tire pressure is properly
adjusted.
Page 784 of 1014

7606-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Low profile tires (except 225/50R17 tires)
Generally, low profile tires will wear more rapidly and tire grip performance
will be reduced on snowy and/or icy roads when compared to standard tires.
Be sure to use snow tires or tire chains on snowy and/or icy roads and drive
carefully at a speed appropriate for road and weather conditions. (P. 436)
If the tread on snow tires wears down below 4 mm (0.16 in.)
The effectiveness of the tires as snow tires is lost.
Situations in which the tire pressure warning system may not operate properly
(vehicles with the tire pressure warning system)
In the following cases, the tire pressure warning system may not operate
properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equip-
ment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• Lock nuts are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the
wheels or wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large
display, airport or other facility that generates strong radio waves or elec-
trical noise
• When carrying a portable radio, cellular phone, cordless phone or other
wireless communication device
Vehicles with the tire inflation pressure display function: If tire position
information is not correctly displayed due to the radio wave conditions, the
display may be corrected by driving and changing the radio wave condi-
tions.
When the vehicle is parked, the time taken for the warning to start or go off
could be extended.
When tire inflation pressure declines rapidly for example when a tire has
burst, the warning may not function.