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IS350/250_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, ti re pressure warning valves, transmitters
and tire valve caps
●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
transmitter 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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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
Fuse layout and amperage ratings■ Engine compartment (type A fuse box)
FuseAmpereCircuit
1PWR HTR25 A
2TURN-HAZ15 AEmergency flashers, turn signals
3IG2 MAIN20 AIG2, IGN, GAUGE
4RAD NO.230 AAudio
5D/C CUT20 ADOME, MPX-B
6RAD NO.130 A
7MPX-B10 A
Headlights, front fog lights, parking
lights, license plate lights, windshield
washer, horn, power door lock system,
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, multiplex
communication system
8DOME10 AInterior lights, meter, outer foot lights
9CDS10 AElectric cooling fans
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4-3. Do-it-yourself maintenance
IS350/250_U■
Engine compartment (type B fuse box)
FuseAmpereCircuit
1SPARE30 ASpare fuse
2SPARE25 ASpare fuse
3SPARE10 ASpare fuse
4FR CTRL-B25 AH-LP UPR, HORN
5A/F15 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
6ETCS10 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
7ALT-S7. 5 ACharging system
8TEL10 ATEL
9STR LOCK25 ASteering lock
10H-LP CLN30 AHeadlight cleaner
11A/C COMP7. 5 AAir conditioning system
12DEICER25 AWindshield wiper de-icer
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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
13FR CTRL-AM30 AFR TAIL, FR FOG, WASHER
14IG210 AIgnition system
15EFI NO.210 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
16H-LP R LWR15 AHeadlight low beam (right)
17H-LP L LWR15 AHeadlight low beam (left)
18F/ P M P25 AFuel system
19EFI25 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem, EFI NO.2
20INJ20 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
21H-LP UPR15 AHeadlight high beams
22HORN10 AHorns
23WA S H E R20 AWindshield washer
24FR TAIL10 AParking lights
25FR FOG15 AFront fog lights
FuseAmpereCircuit
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4-3. Do-it-yourself maintenance
IS350/250_U■
Driver’s side instrument panel
FuseAmpereCircuit
1FR P/SEAT LH30 APo w e r s e a t
2A/C7. 5 AAir conditioning system
3MIR HTR15 AOutside rear view mirror defoggers
4TV NO.110 ADisplay
5FUEL OPEN10 AFuel filler door opener
6TV NO.27. 5 A
7PSB30 A
8S/ROOF25 AMoon roof
9TA I L10 ATail lights, license plate lights, parking
lights
10PA N E L7. 5 ASwitch illumination, air conditioning
system, display, audio
11RR FOG7. 5 A
12ECU-IG LH10 A
Cruise control, air conditioning sys-
tem, power steering, rain sensor, anti-
glare inside rear view mirror, shift lock
system, moon roof, tire inflation pres-
sure warning system, VSC
13FR S/HTR LH15 ASeat heaters and ventilators
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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
14RR DOOR LH20 APo w e r w i n d o w s
15FR DOOR LH20 APower windows, outside rear view
mirror
16SECURITY7. 5 ASmart access system with push-button
start
17H-LP LVL7. 5 AAutomatic headlight leveling system
18LH-IG10 A
Charging system, headlight cleaner,
rear window defogger, electric cool-
ing fans, emergency flashers, turn sig-
nal lights, back-up lights, stop lights,
mirror heaters, rear sun shade, seat
belts, intuitive parking assist, cruise
control, air conditioning system, PTC
heater, manual transmission, wind-
shield wiper de-icer
19FR WIP30 AWindshield wipers
FuseAmpereCircuit
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4-3. Do-it-yourself maintenance
IS350/250_U■
Passenger’s side instrument panel
FuseAmpereCircuit
1FR P/SEAT RH30 APo w e r s e a t
2DOOR DL15 A
3OBD7. 5 AOn-board diagnosis system
4STOP SW7. 5 A
Stop lights, multiport fuel injection sys-
tem/sequential multiport fuel injection
system, VDIM, shift lock system, high
mounted stop light
5TI & TE20 AElectric tilt and telescopic steering
column
6RAD NO.310 AAudio
7GAUGE7. 5 AMeter
8IGN10 A
SRS airbag system, steering lock sys-
tem, multiport fuel injection system/
sequential multiport fuel injection sys-
tem, stop lights
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4
Maintenance and care
IS350/250_U
9ACC7. 5 A
Clock, air conditioning system, audio,
navigation system, outside rear view
mirrors, Lexus parking assist monitor,
glove box light, console box light, mul-
tiplex communication system, display,
smart access system with push-but-
ton start
10CIG15 ACigarette lighter
11PWR OUTLET15 APo w e r o u t l e t
12RR DOOR RH20 APo w e r w i n d o w s
13FR DOOR RH20 A
Po w e r w i n d o w s , o u t s i d e r e a r v i e w
mirrors, multiplex communication sys-
tem
14AM27. 5 AStarting system
15RH-IG7. 5 A
Seat belts, intuitive parking assist,
automatic transmission, seat heater
and ventilator, windshield wiper de-
icer
16FR S/HTR RH15 ASeat heaters and ventilators
17ECU-IG RH10 A
Power seats, smart access system with
push-button start, AWD system, out-
side rear view mirrors, VDIM, air con-
ditioning system, electric tilt and
telescopic steering, power windows,
navigation system, multiplex commu-
nication system
FuseAmpereCircuit