tire pressure Lexus GS250 2012 User Guide

2804-5. Using the driving support
GS350/250_EE (OM30C36E)
After the vehicle has been parked in the sun
The LKA system functions may not be available and a warning message
(P. 767) will be displayed for a while after driving has started. In such
cases, turn the LKA system off and turn it on again after normal temperature
returns. When the temperature in the cabin decreases and the temperature
around the camera sensor (P. 274) becomes suitable for its operation, the
functions will begin to operate.
If there are lane markers on only one side of the vehicle
The lane keeping assist function will not operate. Also, the lane departure
warning will not operate for the side on which lane markers could not be rec-
ognized.
Conditions in which the function may not operate correctly
In the following conditions, the LKA system functions may not operate, or it
may not be possible to ensure adequate performance. Also, the camera sensor
may be unable to recognize lane lines causing the lane departure warning
function to operate incorrectly, or the lane keeping assist function may not
operate properly. However, this does not indicate a malfunction.
When driving through an area with no lane markers, such as a tollbooth, a
crossing or before a ticket checkpoint
When driving on a sharp curve
When lanes are extremely narrow or extremely wide
When the vehicle leans to one side an unusual amount due to a heavy load
or improper tire inflation pressure
When the following distance between your vehicle and the vehicle ahead is
extremely short
When the lane markers are yellow (These may be more difficult for the sys-
tem to recognize compared to white markers.)
When the lane markers are broken, “Raised pavement marker” or stones
When lane markers are obscured or partially obscured by sand, dirt, etc.
When there are shadows on the road running parallel with lane markers, or
if a shadow covers the lane markers
When driving on a particularly bright road surface, such as concrete
When driving on a road surface that is bright due to reflected light
When driving in a location where the light level changes rapidly, such as the
entrance to or exit from a tunnel
When sunlight or the headlights of oncoming vehicles are shining directly
into the camera lens

2824-5. Using the driving support
GS350/250_EE (OM30C36E)
CAUTION
Situations unsuitable for LKA
Do not use LKA in any of the following situations.
Otherwise, the system may not function correctly and could result in an
accident.
When driving with snow tires, tire chains, a spare tire, or similar equip-
ment
When the tires have been excessively worn, or when the tire inflation
pressure is low
When there are objects or structures along the roadside that might be mis-
interpreted as lane markers (such as guardrails, curb, reflector posts, etc.)
When driving on snowy roads
When pavement lane markers are difficult to see due to rain, snow, fog,
etc.
When there are visible lines on the pavement from road repairs, or if the
remains of old lane markers are still visible on the road
When driving on slippery roads, such as those covered with rain, ice or
snow
When driving in a lane other than the driving or passing lanes on a free-
way or highway
When driving on a road with lane closures due to maintenance, or when
driving in a temporary lane
When towing a trailer
NOTICE
To prevent damage to or incorrect operation of the LKA system
Do not modify the headlights or attach stickers to the surface of the lights.
Do not modify the suspension, or replace them with non-genuine parts.
Do not install or place anything on the hood or the grille. Also, do not
install a grille guard (bull bars, kangaroo bar etc.).
Do not modify the sun visor or replace it with anything other than a genu-
ine Lexus product.
If your windshield needs repairs, contact any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.

3404-5. Using the driving support
GS350/250_EE (OM30C36E)
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.

3634-6. Driving tips
4
Driving
GS350/250_EE (OM30C36E)
CAUTION
Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of vehicle control and cause death or
serious injury.
Use tires of the specified size.
Maintain the recommended level of air pressure.
Do not drive at speeds in excess of the speed limit or the speed limit spec-
ified for the snow tires being used.
Use snow tires on all, not just some wheels.
Do not use LKA (Lane-Keeping Assist) system.
Driving with tire chains (vehicles without 19 inch tires)
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in the vehicle being unable to be driven safely,
and may cause death or serious injury.
Do not drive in excess of the speed limit specified for the tire chains being
used, or 50 km/h (30 mph), whichever is lower.
Avoid driving on bumpy road surfaces or over potholes.
Avoid sudden acceleration, abrupt steering, as well as sudden braking and
shifting operation to engine braking.
Slow down sufficiently before entering a curve to ensure that vehicle con-
trol is maintained.
Do not use LKA (Lane-Keeping Assist) system.

3644-6. Driving tips
GS350/250_EE (OM30C36E)
NOTICE
Repairing or replacing snow tires
Request repairs or replacement of snow tires from Lexus dealers or legiti-
mate tire retailers.
This is because the removal and attachment of snow tires affects the opera-
tion of the tire pressure warning valves and transmitters.
Fitting tire chains (vehicles without 19 inch tires)
The tire pressure warning valves and transmitters may not function cor-
rectly when tire chains are fitted.
When standing the windshield wipers up
Raise the wipers in line with the windshield. (P. 362)
Failure to do so may result in damage to the wipers and/or the hood.

643
6Maintenance and care
GS350/250_EE (OM30C36E)
6-1. Maintenance and care
Cleaning and protecting
the vehicle exterior ......... 644
Cleaning and protecting
the vehicle interior .......... 648
6-2. Maintenance
Maintenance
requirements ................... 651
6-3. Do-it-yourself maintenance
Do-it-yourself service
precautions...................... 654
Hood ................................. 657
Positioning a floor jack ..... 658
Engine compartment ......... 660
Tires .................................. 672
Tire inflation pressure ....... 689
Wheels .............................. 691
Air conditioning filter ....... 693
Electronic key battery ....... 695
Checking and replacing
fuses ................................ 698
Light bulbs ........................ 720

655 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS350/250_EE (OM30C36E)
Light bulbs (P. 722)
• Bulb with same number and watt-
age rating as original
• Phillips-head screwdriver
• Flathead screwdriver
•Wrench
Radiator and condenser (P. 667)
Tire inflation pressure (P. 691)• Tire pressure gauge
• Compressed air source
Wa s h e r f l u i d (P. 671)
• 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
Keep hands, clothing and tools away from the moving fan and engine
drive belt.
Be careful not to touch the engine, 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 or the battery.
Fuel and battery fumes are flammable.
Be extremely cautious when working on the battery. It contains poisonous
and corrosive sulfuric acid.
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 discomfort, consult a doctor.
ItemsParts and tools

6726-3. Do-it-yourself maintenance
GS350/250_EE (OM30C36E)
Tires
New tread
Treadwear indicator
Worn tread
The location of treadwear indica-
tors is shown by the “TWI” or “”
marks, etc., molded on the sidewall
of each tire.
Check spare tire condition and
pressure if not rotated.
Replace or rotate tires in accordance with maintenance schedules
and treadwear.
Checking tires
1
2
3

673 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS350/250_EE (OM30C36E)Rotate the tires in the order shown.
To equalize tire wear and help extend tire life, Lexus recommends
that tire rotation is carried out approximately every 10000 km
(6000 miles) for 2WD models or 5000 km (3000 miles) for AWD
models.
Do not fail to initialize the tire pressure warning system after tire
rotation. (vehicle with the tire pressure warning system)
Tire rotation
Vehicles with front and rear
tires of the same size and
without a full-size spare tireVehicles with front and rear
tires of the same size and
with a full-size spare tire
Vehicles with front and rear
tires of differing sizes and
without a full-size spare tireVehicles with front and rear
tires of differing sizes and
with a full-size spare tire
FrontFront
FrontFront

6746-3. Do-it-yourself maintenance
GS350/250_EE (OM30C36E)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. 753)
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. 772)
The tire pressure detected by the tire pressure warning system
can be displayed on the multi-information display. (P. 106)
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. 676)
Tire pressure warning system (if equipped)