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IS250C/350C_U
■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits, cracks deep enough to expose the
fabric or bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or
location of a cut or other damage
If you are not sure, consult with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered,
the tire pressure warning system will not work properly. After driving for about 20
minutes, the tire pressure warning light come s on after blinking for 1 minute to indi-
cate a system malfunction.
■Tire lif e
Any tire over 6 years old must be checked by a qualified technician even if they
have seldom or never been used or damage is not obvious.
■If the tread wears down below 0.16 in. (4 mm) on snow tires
The effectiveness of snow tires is lost.
■Low profile tires
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when compared to standard tires. Be sure to
use snow tires or tire chains
* on snowy and/or icy roads and drive carefully at a
speed appropriate for road and weather conditions.
*: Tire chains cannot be mounted on 18-inch tires.
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IS250C/350C_U
NOTICE
■To avoid damage to the tire pressure warning valves and transmitters
When a tire is repaired with liquid sealants, 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. 4 3 2 )
■Driving on rough roads
Take particular care when driving on roads with loose surfaces or pot holes.
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 and wheels
Low profile tires may cause greater damage than usual to the tire wheel when
receiving impact from the road surface. Therefore 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 pot holes, uneven pavement, curbs and other road hazards.
Failure to do so may lead to severe tire and wheel damage.
■If tire inflation pressures become low while driving
Do not continue driving, or your tires and/or wheels may be ruined.
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IS250C/350C_U
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 reinstall the tire valve caps.
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 have been lost, replace them as
soon as possible.
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4
Maintenance and care
IS250C/350C_U
Air conditioning filter
The air conditioning filter must be changed regularly to maintain air condi-
tioning efficiency.
■ Removal method
Set the air conditioning system to recirculated mode.
(→P. 2 4 2 )
The air conditioning filter case cannot be removed with the system in
the outside air mode.
Turn the “ENGINE START STOP” switch OFF.
Open the glove box. Lift and
remove the partition.
Remove the filter cover.
Remove the filter case.
STEP1
STEP2
STEP3
STEP4
STEP5
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IS250C/350C_U
■Checking interval
Inspect and replace the air conditioning filter according to the maintenance sched-
ule. In dusty areas or areas with heavy traffic flow, early replacement may be
required. (For scheduled maintenance information, please refer to the “Owner's
Manual Supplement/Scheduled Maintenance”.)
■If air flow from the vents decreases dramatically
The filter may be clogged. Check the filter and replace if necessary.
NOTICE
■When using the air conditioning system
Make sure that a filter is always installed.
Using the air conditioning system without a filter may cause damage to the system.
■Replacement method
Remove the air conditioning fil-
ter from the filter case and
replace it with a new one.
The “↑UP” marks shown on the
filter and the filter case should
be pointing up.
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4
Maintenance and care
IS250C/350C_U
Fuse layout and amperage ratings■ Engine compartment (type A fuse box)
FuseAmpereCircuit
1TURN-HAZ15 AEmergency flashers, turn signals
2IG2 MAIN20 AIG2, IGN, GAUGE
3RAD NO.230 AAudio
4D/C CUT20 ADOME, MPX-B
5RAD NO.130 AAudio
6MPX-B10 A
Headlights, front fog lights, parking
lights, license plate lights, windshield
washer, power windows, power seats,
electric tilt and telescopic steering
column, meter, smart access system
with push-button start, outside rear
view mirrors, air conditioning system,
retractable hardtop, clock
7DOME10 AInterior lights, meter, outer foot lights
8CDS10 APo w e r s o u rc e
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9E/G-B60 AFR CTRL-B, ETCS, ALT-S, A/F, TEL,
STR LOCK
10ABS150 AVDIM
11RH J/B-B30 AFR DOOR RH, AM2
12MAIN30 AH-LP R LWR, H-LP L LWR
13STARTER30 ASmart access system with push-button
start
14LH J/B-B30 AFR DOOR LH, SECURITY
15P/ I - B60 AINJ, F/PMP, EFI
16EPS80 APo w e r s t e e r i n g
17ALT150 A
LH J/B-AM, E/G-AM, GLW PLG2,
HEATER, FAN1, FAN2, ABS2, RH
J/B-AM, GLW PLG1, RR R/B-AM
18RR R/B-AM80 A
DEFOG, PSB, ROOF RH, ROOF
LH, LGG RH, LGG LH, LGG LCK
RH, LGG LCK LH, P-TRAY MAIN,
P-T R AY S I D E
19GLW PLG150 APTC heater
20RH J/B-AM80 A
OBD, STOP SW, TI&TE, FR P/SEAT
RH, RAD NO.3, ECU-IG RH,
RH-IG, FR S/HTR RH, ACC, CIG,
PWR OUTLET, DOOR DL
21ABS230 AVDIM
22FA N 240 AElectric cooling fans
23FA N 140 AElectric cooling fans
24HEATER50 AAir conditioning system
25GLW PLG250 APTC heater
FuseAmpereCircuit
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Engine compartment (type B fuse box)
FuseAmpereCircuit
1SPARE30 ASpare fuse
2SPARE25 ASpare fuse
3SPARE10 ASpare fuse
4FR CTRL-B25 AHeadlight high beam, HORN
5A/F15 AExhaust system
6ETCS10 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
7ALT-S7. 5 ACharging system
8TEL10 ALexus Enform
9STR LOCK25 ASteering lock system
10H-LP CLN30 AHeadlight cleaner
11A/C COMP7. 5 AAir conditioning system
12DEICER25 AWindshield wiper de-icer
13FR CTRL-AM30 AWASHER, FR TAIL, FR FOG