inflation pressure Lexus GS350 2015 Refueling / LEXUS 2015 GS350 (OM30E15U) Owner's Manual

GS350_OM_OM30E15U_(U)
4216-3. Do-it-yourself maintenance
6
Maintenance and care
Ti r e v a l v e
Tire pressure gauge
Remove the tire valve cap.
Press the tip of the tire pressure gauge onto the tire valve.
Read the pressure using the gauge gradations.
If the tire inflation pressure is not at the recommended level, adjust the
pressure.
If you add too much air, press the center of the valve to deflate.
After completing the tire inflation pressure measurement and adjust-
ment, apply soapy water to the valve and check for leakage.
Put the tire valve cap back on.
■Tire inflation pressure check interval
You should check tire inflation pressure every two weeks, or at least once a month.
Do not forget to check the spare.
■Effects of incorrect tire inflation pressure
Driving with incorrect tire inflation pressure may result in the following:
●Reduced fuel efficiency
●Reduced driving comfort and tire life
●Reduced safety
●Damage to the drive train
If a tire needs frequent inflating, have it checked by your Lexus dealer.
Inspection and adjustment procedure
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6-3. Do-it-yourself maintenance
■Instructions for checking tire inflation pressure
When checking tire inflation pressure, observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at least 3 hours or has not been driven for more
than 1 mile or 1.5 km, you will get an accurate cold tire inflation pressure reading.
●Always use a tire pressure gauge.
The appearance of the tire can be misleading. In addition, tire inflation pressure that
is even just a few pounds off can affect ride quality and handling.
●Do not reduce tire inflation pressure after driving. It is normal for tire inflation pres-
sure to be higher after driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle is balanced.
CAUTION
■Proper inflation is critical to save tire performance
Keep your tires properly inflated. Otherwise, the following conditions may occur
and result in an accident causing death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overheated tires
●Poor sealing of the tire bead
●Wheel deformation and/or tire separation
●A greater possibility of tire damage from road hazards
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to put the tire valve caps back on.
Without the valve caps, dirt or moisture could get into the valve and cause air leak-
age, which could result in an accident. If the caps are lost, replace them as soon as
possible.

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6-3. Do-it-yourself maintenance
■When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning valves and trans-
mitters that allow the tire pressure warnin g system to provide advance warning in the
event of a loss in tire inflation pressure. Whenever wheels are replaced, tire pressure
warning valves and transmitte rs must be installed. (P. 4 1 2 )
CAUTION
■When replacing wheels
●Do not use wheels that are a different size from those recommended in the
Owner’s Manual, as this may result in a loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a tubeless tire.
Doing so may result in an accident, causing death or serious injury.
●2WD F SPORT models: Do not install steel wheels.
The wheel contact surface could be da maged, and the wheel could come off
while driving, which could lead to an accid ent resulting in death or serious injury.
■Use of defective wheels prohibited
Do not use cracked or deformed wheels.
Doing so could cause the tire to leak air during driving, possibly causing an acci-
dent.
NOTICE
■Replacing tire pressure warning valves and transmitters
●Because tire repair or replacement may affect the tire pressure warning valves
and transmitters, make sure to have tires serviced by your Lexus dealer or other
qualified service shop. In addition, make sure to purchase your tire pressure
warning valves and transmitters at your Lexus dealer.
●Ensure that only genuine Lexus wh eels are used on your vehicle.
Tire pressure warning valves and transmitters may not work properly with non-
genuine wheels.

4747-2. Steps to take in an emergency
GS350_OM_OM30E15U_(U)
*1: Open door warning buzzer: P. 4 8 7
*2: Driver’s seat belt buzzer:
The driver’s seat belt buzzer sounds to al ert the driver that his or her seat belt is
not fastened. Once the engine switch is turned to IGNITION ON mode, the
buzzer sounds for 6 seconds. If the vehicle reaches a speed of 12 mph (20 km/h),
the buzzer sounds once. If the seat belt is still unfastened after 24 seconds, the
buzzer will sound intermittently for 10 seco nds. Then, if the seat belt is still unfas-
tened, the buzzer will sound in a different tone for 20 more seconds.
Front passenger’s seat belt buzzer:
The front passenger’s seat belt buzzer soun ds to alert the front passenger that his
or her seat belt is not fastened. The buzzer sounds once if the vehicle reaches a
speed of 12 mph (20 km/h). If the seat belt is still unfastened after 24 seconds, the
buzzer will sound intermittently for 10 seco nds. Then, if the seat belt is still unfas-
tened, the buzzer will sound in a different tone for 20 more seconds.
Tire pressure warning light
When the light comes on:
Low tire inflation pressure such
as • Natural causes ( P. 4 76 )
• Flat tire ( P. 5 0 4 )
Adjust the tire inflation pressure
to the specified level.
The light will turn off after a
few minutes. In case the light
does not turn off even if the
tire inflation pressure is
adjusted, have the system
checked by your Lexus
dealer.
When the light comes on after
blinking for 1 minute:
Malfunction in the tire pressure
warning system
Have the system checked by
your Lexus dealer.
Warning lightWarning light/DetailsCorrection procedure

4757-2. Steps to take in an emergency
GS350_OM_OM30E15U_(U)
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When trouble arises
■SRS warning light
This warning light system monitors the airbag sensor assembly, front impact sensors,
side impact sensors (front door), side impact sensors (front), side impact sensors
(rear), driver’s seat position sensor, driver’s seat belt buckle switch, front passenger
occupant classification system, “AIR BAG ON” indicator light, “AIR BAG OFF” indi-
cator light, front passenger’s seat belt buckle switch, seat belt pretensioner assem-
blies, airbags, interconnectin g wiring and power sources. ( P. 38)
■Front passenger detection sensor, seat belt reminder and warning buzzer
If luggage is placed on the front passen ger seat, the front passenger detection sen-
sor may cause the warning light to flash and the warning buzzer to sound even if a
passenger is not sitting in the seat.
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving trips.
If the light does not go off even after several trips, contact your Lexus dealer as soon
as possible.
■Electric power steering system warning light (warning buzzer)
When the 12-volt battery charge becomes insufficient or the voltage temporarily
drops, the electric power steering system warning light may come on and the warn-
ing buzzer may sound.
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pushing the tire
pressure warning reset switch will not turn off the tire pressure warning light.

4767-2. Steps to take in an emergency
GS350_OM_OM30E15U_(U)
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural
air leaks and tire inflation pressure changes caused by temperature. In this case,
adjusting the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with a tire pressure warning valve and trans-
mitter. If a tire goes flat, the tire pressure warning light will not turn off even though
the flat tire has been replaced with the spare tire.
■Conditions that the tire pressure warning system may not function properly
 P. 4 1 6
■If the tire pressure warning light freque ntly comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute when
the engine switch is turned to IGNITION ON mode, have it checked by your Lexus
dealer.
■Warning buzzer
In some cases, the buzzer may not be he ard because of noisy place or an audio
sound.
■Customization
The vehicle speed linked seat belt reminder buzzer can be disabled.
(Customizable features: P. 5 6 1 )

4777-2. Steps to take in an emergency
GS350_OM_OM30E15U_(U)
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When trouble arises
CAUTION
■If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact your Lexus dealer. The
vehicle will become extremely unstable during braking, and the ABS system may
fail, which could cause an accident resulting in death or serious injury.
■When the electric power steering system warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, hold firmly and
operate using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause a loss of
vehicle control and result in death or serious injury.
●Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pres-
sure immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust-
ment, it is probable that you have a flat tire. Check the tires. If a tire is flat, change
it with the spare tire and have the flat tire repaired by the nearest Lexus dealer.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could
lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.

4787-2. Steps to take in an emergency
GS350_OM_OM30E15U_(U)
CAUTION
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold
and inflated to the inflation pressure re commended by the vehicle manufacturer on
the vehicle placard or tire inflation pressu re label (tire and load information label).
(If your vehicle has tires of a different size than the size indicated on the vehicle
placard or tire inflation pressure label [t ire and load information label], you should
determine the proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire pressure
monitoring system (TPMS-tire pressure wa rning system) that illuminates a low tire
pressure telltale (tire pressure warning light ) when one or more of your tires is sig-
nificantly under-inflated. Accordingly, when the low tire pressure telltale (tire pres-
sure warning light) illuminates, you should stop and check your tires as soon as
possible, and inflate them to the proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can lead to tire failure. Under-inflation
also reduces fuel efficiency and tire tread life, and may affect the vehicle’s handling
and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a substitute for
proper tire maintenance, and it is the driver’s responsibility to maintain correct tire
pressure, even if under-inflation has not re ached the level to trigger illumination of
the TPMS low tire pressure telltale (tire pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warning system)
malfunction indicator to indicate when th e system is not operating properly. The
TPMS (tire pressure warning system) malfunction indicator is combined with the
low tire pressure telltale (tire pressure warning light). When the system detects a
malfunction, the telltale will flash for approximately one minute and then remain
continuously illuminated. This sequence will continue upon subsequent vehicle
start-ups as long as the malfunction exists . When the malfunction indicator is illumi-
nated, the system may not be able to detect or signal low tire pressure as intended.

4957-2. Steps to take in an emergency
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When trouble arises
Wa r n i n g m e s s a g eDetailsCorrection procedure
(If equipped)
Indicates that the tire
inflation pressure is lowCheck the tire inflation
pressure, and adjust to
the appropriate level.
(If equipped)
Indicates a malfunction in
the tire pressure warning
system
Stop the vehicle in a safe
place and turn the engine
switch off then on again.If the tire pressure
warning indicator
flashes for 1 minute
then illuminates, there
is a malfunction in the
system. Have the vehi-
cle inspected at your
Lexus dealer.
(If equipped)
Indicates that the tire
position information can-
not be recognized
Drive for a short while
and check if the display
updates.If the radio wave condi-
tions improve, the dis-
play may return to
normal. If the tire pres-
sure is still not dis-
played after driving for
several minutes, stop
the vehicle in a safe
place, turn the engine
switch off then on
again, and start driving.
If the tire pressure is still
not displayed even
after repeating this sev-
eral times, have the
vehicle inspected at
your Lexus dealer.

5147-2. Steps to take in an emergency
GS350_OM_OM30E15U_(U)
■The compact spare tire
●The compact spare tire is identified by the label “TEMPORARY USE ONLY” on
the tire sidewall.
Use the compact spare tire temporarily, and only in an emergency.
●Make sure to check the tire inflation pressure of the compact spare tire.
( P. 5 4 3 )
■When using the compact spare tire
As the compact spare tire is not equipped with a tire pressure warning valve and
transmitter, low inflation pressure of the spare tire will not be indicated by the tire
pressure warning system. Also, if you replace the compact spare tire after the tire
pressure warning light comes on, the light remains on.
■When the compact spare tire is equipped
The vehicle becomes lower when driving wi th the compact spare tire compared to
when driving with standard tires.
■If you have a flat rear tire on a road covered with snow or ice (vehicles with front
and rear tires of the same size)
Install the compact spare tire on one of th e front wheels of the vehicle. Perform the
following steps and fit tire chains to the rear tires:
Replace a front tire with the compact spare tire.
Replace the flat rear tire with the tire removed from the front of the vehicle.
Fit tire chains to the rear tires.
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