2015 Lexus GS450h tire pressure

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Maintenance and care
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as dangerous
handling characteristics, which may lead to an accident resulting in death or seri-
ous injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix differently constructed tires (r adial, bias-belted or bias-ply tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
■When initializing the tire pressure warning system
Do not operate the tire pressure warning re set switch without first adjusting the tire
inflation pressure to the specified level. Otherwise, the tire pressure warning light
may not come on even if the tire inflation pressure is low, or it may come on when
the tire inflation pressure is actually normal.
■Caution regarding interference with elec tronic devices (vehicles with the tire
inflation pressure display function)
●Users of any electrical medical device other than implantable cardiac pacemak-
ers, cardiac resynchronization therapy-pacemakers or implantable cardioverter
defibrillators should consult the manufacturer of the device for information about
its operation under the influence of radio waves.
Radio waves could have unexpected effects on the operation of such medical
devices.
●People with implantable cardiac pacemak-
ers, cardiac resynchronization therapy-
pacemakers or implantable cardioverter
defibrillators should not come within 17.7 in.
(450 mm) of the tire pressure warning sys-
tem initiators. The radio waves may affect
the operation of such devices.

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6-3. Do-it-yourself maintenance
NOTICE
■Repairing or replacing tires, wheels, tire pressure warning valves, transmitters
and tire valve caps
●When removing or fitting the wheels, tires or the tire pressure warning valves and
transmitters, contact your Lexus dealer as the tire pressure warning valves and
transmitters may be damaged if not handled correctly.
●Make sure to install the tire valve caps. If the tire valve caps are not installed,
water could enter the tire pressure warning valves and the tire pressure warning
valves could be bound.
●When replacing tire valve caps, do not us e tire valve caps other than those speci-
fied. The cap may become stuck.
■To avoid damage to the tire pressu re warning valves and transmitters
When a tire is repaired with liquid seal ants, the tire pressure warning valve and
transmitter may not operate properly. If a liquid sealant is used, contact your Lexus
dealer or other qualified service shop as soon as possible. Make sure to replace
the tire pressure warning valve and transmitter when replacing the tire. ( P. 445)
■Driving on rough roads
Take particular care when driving on roads with loose surfaces or potholes.
These conditions may cause losses in tire inflation pressure, reducing the cushion-
ing ability of the tires. In addition, driving on rough roads may cause damage to the
tires themselves, as well as the vehicle’s wheels and body.
■Low profile tires (except 225/50R17 tires)
Low profile tires may cause greater damage than usual to the tire wheel when sus-
taining impact from the road surface. Th erefore, pay attention to the following:
●Be sure to use proper tire inflation pressure. If tires are under-inflated, they may
be damaged more severely.
●Avoid potholes, uneven pavement, curbs and other road hazards. Failure to do so
may lead to severe tire and wheel damage.
■If tire inflation pressure of each tire becomes low while driving
Do not continue driving, or your tires and/or wheels may be ruined.

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GS450h_OM_OM30F70U_(U)6-3. Do-it-yourself maintenance
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Maintenance and care
Tire inflation pressure
The recommended cold tire infla-
tion pressure and tire size are dis-
played on the tire and loading
information label. ( P. 582)
Tire inflation pressure

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6-3. Do-it-yourself maintenance
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 economy
●Reduced driving comfort and poor handling
●Reduced tire life due to wear
●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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Maintenance and care
■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.
It is difficult to judge if a tire is properly inflated based only on its appearance.
●It is normal for the tire inflation pressure to be higher after driving as heat is gener-
ated in the tire. Do not reduce tire inflation pressure 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.
If the tires are not properly inflated, the following conditions may occur which
could lead to an accident resulting in death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overheated tires
●Air leaking from between tire and wheel
●Wheel deformation and/or tire damage
●Greater possibility of tire damage while driving (due to road hazards, expansion
joints, sharp edges in the road, etc.)
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to put the tire valve caps back on.
If a valve cap is not installed, dirt or moisture may get into the valve and cause an air
leak, resulting in decreased tire inflation pressure.

GS450h_OM_OM30F70U_(U)
4576-3. Do-it-yourself maintenance
6
Maintenance and care
■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. 445)
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.
●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.

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6-3. Do-it-yourself maintenance
■Passenger’s side instrument panel
FuseAmpereCircuit
1P/ S E AT 1 F/ R30Po w e r s e a t s
2FR P/OUTLET15Po w e r o u t l e t ( f r o n t )
3RR P/OUTLET15Power outlet (rear)
4P/ S E AT 2 F/ R25Po w e r s e a t s
5AV S20AV S
6STRG HTR15Heated steering wheel
7WA S H20Windshield washer
8RH ECU-IG10
Navigation system, VGRS, pre-collision seat
belts, air conditioning system, brake system,
Lexus night view, yaw rate and G sensor,
capacitor, Dynamic rear steering
9RH-IG10
Tension reducer, seat heater/ventilator
switches, front right-hand door ECU, CAN
gateway ECU, tire pressure warning system,
power seats
10DOOR FR30
Front right-hand door control system (out-
side rear view mirror defoggers, power win-
dow)
11DOOR RR30Power window (rear right-hand)
12RAD NO.230Audio system
13AM27. 5Power management system

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■Trunk
FuseAmpereCircuit
1PSB30Pre-collision seat belts
2PTL25Power trunk opener and closer
3RR J/B-B10Smart access system with push-button start
4RR S/HTR20Seat heaters (rear)
5FR S/HTR10Seat heaters/ventilators (front)
6RR FOG10No circuit
7DC/DC-S (HV)7. 5DC/DC converter
8BATT FAN (HV)20Hybrid battery (traction battery) cooling fan
system
9SECURITY7. 5SECURITY
10ECU-B NO.37. 5Parking brake
11TRK OPN7. 5Power trunk opener and closer, trunk open
motor
12DCM (HV)7. 5DCM
13AC INV (HV )20Po w e r o u t l e t ( 1 2 0 V AC )
14RR-IG15Radar sensor, Blind Spot Monitor
15RR ECU-IG10
Power trunk opener and closer, parking
brake, tension reducer (rear left-hand), RR
CTRL SW, tire pressure warning system
16EPS-IG5Electric power steering system
17BACK UP7. 5Back-up lights, Remote Touch screen