2010 Lexus IS250C warning

5
When trouble arises
481
5-2. Steps to take in an emergency
10_IS250C/350C_U
■Changing the engine oil (U.S.A. only)
Make sure to reset the oil change system. (→P. 3 9 5 )
■Warning light display in radar cruise mode
In the following cases, the warning light may not be displayed even if vehicle-to-
vehicle distance closes.
●When your vehicle and the vehicle ahead are traveling at the same speed or the
vehicle ahead is traveling more quickly than your vehicle
●When the vehicle ahead is traveling at a very low speed
●Immediately after cruise control speed is set
●At the instant the accelerator pedal is depressed

482
5-2. Steps to take in an emergency
10_IS250C/350C_U
Follow the correction procedures.After taking the specified steps to correct the suspected problem, check
that the warning light turns off.
InteriorbuzzerExterior buzzerMessageDetailsCorrection
procedure
Once
(Comes on for 10 seconds.)
(Flashing)
Indicates that an
attempt was made
to start the engine
without the elec-
tronic key being
present, or the
electronic key was
not functioning
normally.
Start the engine
with the elec-
tronic key
present.
*
Once3 times
(Flashing)
Indicates that a
door other than
the driver’s door
has been opened
or closed with the
“ENGINE START
STOP” switch in
any mode other
than OFF and the
electronic key
outside of the
detection area.
Confirm the loca-
tion of the elec-
tronic key.

5
When trouble arises
491
5-2. Steps to take in an emergency
10_IS250C/350C_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 only in an emergency.
●Make sure to check the tire pressure of the compact spare tire. (→P. 5 3 6 )
■When using the compact spare tire
As the compact spare tire is not equipped with the tire pressure warning valve and
transmitter, low inflation pressure of the spare tire will not be warned. Also, if you
replace the compact spare tire after the tire pressure warning light comes on, the
light remains on.
■If you have a flat rear tire on a road covered with snow or ice
Install the compact spare tire on the front 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 vehi-
cle.
Fit tire chains to the rear tires.
■After completing the tire change
The tire pressure warning system must be reset. ( →P. 4 0 7 )
STEP1
STEP2
STEP3

494
5-2. Steps to take in an emergency
10_IS250C/350C_U
NOTICE
■Do not drive the vehicle with a flat tire.
Do not continue driving with a flat tire.
Driving even a short distance with a flat tire can damage the tire and the wheel
beyond repair.
■Be careful when driving over bumps with the compact spare tire installed on the
vehicle.
The vehicle becomes lower when driving with the compact spare tire compared to
when driving with standard tires. Be careful when driving over uneven road sur-
faces.
■Driving with tire chains and the compact spare tire
Do not fit tire chains to the compact spare tire.
Tire chains may damage the vehicle body and adversely affect driving performance.
■When replacing the tires
When removing or fitting the wheels, tires or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and trans-
mitter may be damaged if not handled correctly.
■To avoid damaging the tire pressure warning valves and transmitters
When a tire is repaired with the emergency tire puncture repair kit, the tire pressure
warning valve and transmitter may not operate properly. If the emergency tire
puncture repair kit is used, replace the tire pressure warning valve and transmitter
when replacing the tire.

5
When trouble arises
495
5-2. Steps to take in an emergency
10_IS250C/350C_U
If you have a flat tire (vehicles with run-flat tires)
■In some condition (such as at high temperatures)
You cannot continue driving for up to 100 miles (160 km).
■If you cannot distinguish between the standard tires and run-flat tires
Consult your Lexus dealer.
■Spare tire
A spare tire is not provided on the vehicle with run-flat tires.
■For the detailed information on run-flat tires
See the tire warranty book.
Take your vehicle to the nearest Lexus dealer or authorized tire dealer as
soon as possible.
■ Run-flat tires (A “RFT” or “DSST” mark is molded on the sidewall)
You can continue driving a vehi-
cle with run-flat tires even if any
tire goes flat.
It is able to run for a maximum of
100 miles (160 km) at a speed
below 50 mph (80 km/h) after
the tire pressure warning light
comes on. ( →P. 4 6 5 )

496
5-2. Steps to take in an emergency
10_IS250C/350C_U
NOTICE
■When replacing the tires
When removing or fitting the wheels, tires or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and trans-
mitter may be damaged if not handled correctly.
■To avoid damaging the tire pressure warning valves and transmitters
When a tire is repaired with the emergency tire puncture repair kit, the tire pressure
warning valve and transmitter may not operate properly. If the emergency tire
puncture repair kit is used, replace the tire pressure warning valve and transmitter
when replacing the tire.

549
6-1. Specifications
6
Vehicle specifications
10_IS250C/350C_U■
DOT quality grades
All passenger vehicle tires must conform to Federal Safety Require-
ments in addition to these grades. Quality grades can be found where
applicable on the tire sidewall between tread shoulder and maximum
section width.
For example: Treadwear 200 Traction AA Temperature A
■Treadwear
The treadwear grade is a comparative rating based on the wear rate of
the tire when tested under controlled conditions on a specified gov-
ernment test course.
For example, a tire graded 150 would wear one and a half (1 - 1 /2) times as
well on the government course as a tire graded 100.
The relative performance of tires depends upon the actual conditions of
their use, however, and may depart sign ificantly from the norm due to varia-
tions in driving habits, service practices and differences in road characteris-
tics and climate.
■ Traction AA, A, B, C
The traction grades, from highest to lowest, are AA, A, B and C, and
they represent the tire's ability to stop on wet pavement as measured
under controlled conditions on specified government test surfaces of
asphalt and concrete.
A tire marked C may have poor traction performance.
Warning: The traction grade assigned to this tire is based on braking
(straight ahead) traction tests and does not include cornering (turning) trac-
tion.

550
6-1. Specifications
10_IS250C/350C_U■
Temperature A, B, C
The temperature grades are A (the highest), B, and C, representing
the tire's resistance to the generation of heat and its ability to dissipate
heat when tested under controlled conditions on a specified indoor
laboratory test wheel.
Sustained high temperature can cause the material of the tire to degenerate
and reduce tire life, and excessive temperature can lead to sudden tire fail-
ure.
The grade C corresponds to a level of performance which all passenger car
tires must meet under the Federal Motor Vehicle Safety Standard No. 139.
Grades B and A represent higher levels of performance on the laboratory
test wheel than the minimum required by law.
Warning: The temperature grades for this tire are established for a tire that
is properly inflated and not overloaded.
Excessive speed, underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
Glossary of tire terminology
Tire related termMeaning
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of automatic transmis-
sion, power steering, power brakes, power windows,
power seats, radio and heater, to the extent that these
items are available as factory-installed equipment
(whether installed or not)
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Curb weight
The weight of a motor vehicle with standard equip-
ment, including the maximum capacity of fuel, oil and
coolant, and if so equipped, air conditioning and
additional weight optional engine