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439
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS250C/350C_U
CAUTION
■Tire pressure warning system operation
The tire pressure warning system may not provide warning immediately if a tire
bursts or if sudden air leakage occurs.
■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 serious 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 (radial, bias-belted or bias-ply tires).
●Do not mix summer, all season and winter 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 press the satellite 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.
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.
●When replacing tire valve caps, do not use tire valve caps other than those speci-
fied. The cap may become stuck.
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496
5-2. Steps to take in an emergency
IS250C/350C_U
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire (vehicles with a spare tire)
The compact spare tire is not equipped with the tire pressure warning valve and
transmitter. If a tire goes flat, the tire pressure warning light will not turn off even
though the flat tire is replaced with the spare tire. Replace the spare tire with the
repaired tire and adjust the proper tire inflation pressure. The tire pressure warning
light will turn off after a few minutes.
■If the tire pressure warning system is inoperative
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 a different set of tires has been selected using the satellite switch.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher
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 frequencies is in use in the vehicle
●If there is a lot of snow or ice on the vehicle, in particular 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 frequently comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute
when the “ENGINE START STOP” switch is turned to IGNITION ON mode, have
it checked by your Lexus dealer.
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510
5-2. Steps to take in an emergency
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.
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5
When trouble arises
511
5-2. Steps to take in an emergency
IS250C/350C_U
Once3 times
(Flashing)
Indicates that the
driver’s door has
been opened or
closed with the
shift lever in P, the
“ENGINE START
STOP” switch in
any mode other
than OFF and the
electronic key
outside of the
detection area.
Tu r n t h e
“ENGINE START
STOP” switch
OFF or confirm
the location of the
electronic key.
OnceCon-
tinuous
(Displayed alternately)(Flashing)
Indicates that the
driver’s door has
been opened or
closed (with the
shift lever out of in
P, t h e “ E N G I N E
START STOP”
switch in any
mode other than
OFF and the elec-
tronic key outside
of the detection
area).
• Shift the shift lever to P.
•Confirm the
location of the
electronic key.
Once
(Flashing)
Indicates that the
key battery is low.Replace the bat-
tery. ( →P. 4 4 9 )
Interior
buzzerExterior buzzerMessageDetailsCorrection
procedure
Page 513 of 626
512
5-2. Steps to take in an emergency
IS250C/350C_U
*: If the engine does not start when the electronic key is inside the vehicle, theelectronic key battery may be depleted or there may be difficulties receiving the
signal from the key. ( →P. 36)
Once
Indicates that a
door has been
opened or closed
and the “ENGINE
START STOP”
switch has been
switched twice to
ACCESSORY
mode from OFF.
Press the
“ENGINE START
STOP” switch
while applying the
brakes.
(Flashing)
Indicates that the
steering lock has
not released
within 3 seconds
of pressing the
“ENGINE START
STOP” switch.Press the
“ENGINE START
STOP” switch
again while turn-
ing the steering
wheel with the
brake pedal
depressed.
OnceIndicates that the
electronic key
does not operate
properly.
→P. 5 3 0
Interior
buzzerExterior buzzerMessageDetailsCorrection
procedure
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5
When trouble arises
531
5-2. Steps to take in an emergency
IS250C/350C_U
■Stopping the engine
Shift the shift lever to P and press the “ENGINE START STOP” switch as you nor-
mally do when stopping the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immediately when the battery depletes. (→P. 4 4 9 )
■Changing “ENGINE START STOP” switch modes
Within 10 seconds of the buzzer sounding, release the brake pedal and press the
“ENGINE START STOP” switch.
The engine does not start and modes w ill be changed each time the switch is
pressed. ( →P. 1 4 8 )
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5
When trouble arises
533
5-2. Steps to take in an emergency
IS250C/350C_U
■Avoiding a discharged battery
●Turn off the headlights and the audio system while the engine is off.
●Turn off any unnecessary electrical components when the vehicle is running at a
low speed for an extended period, such as in heavy traffic, etc.
■Charging the battery
The electricity stored in the battery will discharge gradually even when the vehi-
cle is not in use, due to natural discharge and the draining effects of certain
electrical appliances. If the vehicle is left for a long time, the battery may dis-
charge, and the engine may be unable to start. (The battery recharges automat-
ically during driving.)
■When the battery is removed or discharged
Make sure that the key is not inside the vehicle when recharging or replacing the
battery. The key may be locked in the vehicle if the alarm is activated. (→P. 1 0 1 )
Maintain the engine speed of the second vehicle and turn the
“ENGINE START STOP” switch to IGNITION ON mode,
then start the vehicle’s engine.
Once the vehicle’s engine has started, remove the jumper
cables in the exact reverse order in which they were con-
nected.
Once the engine starts, have the vehicle checked at your Lexus dealer
as soon as possible.STEP5
STEP6
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583
6-1. Specifications
6
Vehicle specifications
IS250C/350C_U
Intended outboard side-
wall
(a) The sidewall that contains a whitewall, bears white lettering, or bears manufacturer, brand,
and/or model name molding that is higher or
deeper than the same molding on the other side-
wall of the tire, or
(b) The outward facing sidewall of an asymmetrical
tire that has a particular side that must always
face outward when mounted on a vehicle
Light truck (LT) tire
A tire designated by its manufacturer as primarily
intended for use on lightweight trucks or multipur-
pose passenger vehicles
Load ratingThe maximum load that a tire is rated to carry for a
given inflation pressure
Maximum load ratingThe load rating for a tire at the maximum permissible
inflation pressure for that tire
Maximum permissible
inflation pressureThe maximum cold inflation pressure to which a tire
may be inflated
Measuring rimThe rim on which a tire is fitted for physical dimension
requirements
Open spliceAny parting at any junction of tread, sidewall, or
innerliner that extends to cord material
Outer diameterThe overall diameter of an inflated new tire
Overall width
The linear distance between the exteriors of the side-
walls of an inflated tire, including elevations due to
labeling, decorations, or protective bands or ribs
Passenger car tire
A tire intended for use on passenger cars, multipur-
pose passenger vehicles, and trucks, that have a
gross vehicle weight rating (GVWR) of 10000 lb. or
less.
PlyA layer of rubber-coated parallel cords
Tire related termMeaning