2010 Lexus HS250h flat tire

447
4-3. Do-it-yourself maintenance
4
Maintenance and care
●Never exceed the vehicle capacity weight. 
Passengers and luggage weight should be placed so that the vehicle is bal-
anced.
CAUTION
■Proper inflation is critical to save tire performance
Keep your tires properly inflated. Otherw ise, the following conditions may occur
and result in an accident cau sing 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.

448
4-3. Do-it-yourself maintenance
Wheels
■When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning valves and
tr
ansmitters that allow the tire pressure warning system to provide advance warning
in the event of a loss in tire inflation pressure. Whenever wheels are replaced, tire
pressure warning valves and transmitters must be installed. ( P. 4 3 8 )
If a wheel is bent, cracked or heavily corroded, it should be replaced.
Otherwise, the tire may separate from the wheel or cause a loss of han
-
dling control.
■ Wheel selection
When replacing wheels, care should be taken to ensure that they
ar

e equivalent to those removed in load capacity, diameter, rim
width and inset*. 
Replacement wheels are available at your Lexus dealer.
*: Conventionally referred to as “offset”.
Lexus does not recommend using the following:
● Wheels of dif
ferent sizes or types
● Used wheels
● Bent wheels that ha
ve been straightened
■ Aluminum wheel pr
ecautions
● Use only L
exus wheel nuts and wr enches designed for use with
your aluminum wheels.
● When r
otating, repairing or changi ng your tires, check that the
wheel nuts are still tight after driving 1000 miles (1600 km).
● Be car
eful not to damage the aluminum wheels when using tire
chains.
● Use only L
exus genuine balance weights or equivalent and a
plastic or rubber hammer when balancing your wheels.

463
4-3. Do-it-yourself maintenance
4
Maintenance and care
3IGN10 A
Electronically controlled brake sys-
tem, multiport fuel injection system/
sequential multiport fuel injection sys-
tem, Lexus link system, smart access
system with push-button start, stop
lights
4MET7. 5 AMeters
5WIP30 AWindshield wipers
6WA S H E R15 AWindshield washer
7A/C10 AAir conditioning system
8GAUGE10 AAFS, turn signal lights, emergency
flasher lights
9AFS10 AAdaptive front-lighting system
10ECU-IG NO.210 A
Pre-collision system, LKA, dynamic
radar cruise control, air conditioning
system, outside rear view mirror,
HUD, navigation system, tire inflation
pressure warning system
FuseAmpereCircuit

When trouble arises5
481
5-1. Essential informationEmergency flashers .............. 482
If your vehicle needs to be 
towed ...................................... 483
If you think something is 
wrong ...................................... 489
Event data recorder.............. 490
5-2. Steps to take in an 
emergency
If a warning light turns on 
or a warning buzzer 
sounds..................................... 492
If a warning message is 
displayed................................. 501
If you have a flat tire................ 521
If the hybrid system will not 
start ......................................... 530
If you lose your keys .............. 532
If the electronic key does 
not operate properly.......... 533
If the vehicle 12-volt 
battery is discharged ......... 536
If your vehicle overheats ...... 541
If the vehicle becomes 
stuck........................................ 545

5
When trouble arises
489
5-1. Essential information
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■ Visible symptoms
●Fluid leaks under the v
ehicle
(Water dripping from the air conditioning after use is normal.)
● Flat
-looking tires or uneven tire wear
●High engine coolant temper
ature warning light flashes or comes
on
■ A
udible symptoms
●Changes in e
xhaust sound
● Ex
cessive tire squeal when cornering
●Str
ange noises related to the suspension system
●P
inging or other noises related to the hybrid system
■ Oper
ational symptoms
●Engine mis
sing, stumbling or running rough
●A
ppreciable loss of power
●V
ehicle pulls heavily to one side when braking
●V
ehicle pulls heavily to one side when driving on a level road.
● L
oss of brake effectiveness, sp ongy feeling, pedal almost touches
the floor

496
5-2. Steps to take in an emergency
*1: Open door warning buzzer:
P. 5 0 5
*2: Driver’s and front passenger’s seat belt buzzer:
The driver’s and front passenger’s seat belt buzzer sounds to alert the driver and
front passenger that his or her seat belt is not fastened. The buzzer sounds inter-
mittently for 10 seconds after the vehicle
reaches a speed of 12 mph (20 km/h).
Then, if the seat belt is still unfastened, the buzzer will sound in a different tone
for 20 more seconds.
Tire pressure warning light
When the light comes on: 
Low tire inflation pressureAdjust the tire inflation pres-
sure.
When the light comes on after
blinking for 1 minute: 
Malfunction in the tire pres-
sure warning system
Have the system checked by
your Lexus dealer.
■SRS warning light
This warning light system monitors the airb ag
sensor assembly, front airbag sensors,
side and curtain shield airbag sensors, curtain shield and rear side airbag sensors,
driver’s seat position sensor , driver’s seat belt buckle switch, front passenger occu -
pant classification system, “AIR BAG ON” indicator light, “
AIR BAG OFF” indicator
light, front passenger’s seat belt buckle switch, seat belt pretensioner assemblies,
inflators, interconnecting wiring and power sources. ( P. 1 0 5)
■Front passenger detection sensor, passenger seat belt reminder and warning
buzzer
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash and the warning buzzer to sound
even if a passenger is not sitting in the seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
Warning lightWarning light/DetailsCorrection procedure

5
When trouble arises
497
5-2. Steps to take in an emergency
■Electric power steering warning light (warning buzzer)
The electric power steering warning light comes on and the warning buzzer sounds
when the voltage is low or the voltage drops.
■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.
■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.
■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 chan ges caused by temperature. In this case,
adjusting the tire inflation pressure will turn off the warning light (after a few min-
utes).
■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. Replace the spare tire with the
repaired tire and adjust the tire inflatio n pressure. The tire pressure warning light
will go off after a few minutes.
■If the tire pressure warning system is not functioning
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used.
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher.

498
5-2. Steps to take in an emergency
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby.
●If a radio set at similar frequency is in use in the vehicle.
●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 non-genuine Lexus wheels are used (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used.
■If the tire pressure warning light comes on after flashing frequently for 1 minute
If the tire pressure warning light comes on after flashing frequently for 1 minute
when the “POWER” switch is turned to ON mode, have it checked by your Lexus
dealer.
■Customization that can be configured at Lexus dealer
The vehicle speed linked seat belt reminder buzzer can be disabled. 
(Customizable features P. 5 7 2 )
CAUTION
■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 it 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 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.