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419
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_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.
■Cleaning method
If the filter is dirty, clean by blow-
ing compressed air through the
filter from the downward side.
Hold the air gun 2 in. (5 cm)
from the filter and blow for
approximately 2 minutes at
72 psi (500 kPa, 5.0 kgf/cm
2
or bar).
If it is not available, have the
filter cleaned by your Lexus
dealer.
■ 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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420
4-3. Do-it-yourself maintenance
IS350/250_U
NOTICE
■To prevent damage to the system
●When using the air conditioning system, make sure that a filter is always installed.
●When cleaning the filter, do not clean the filter with water.
Page 431 of 578
430
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 ALexus Enform
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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433
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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526
6-1. Specifications
IS350/250_U
■Gasoline quality
In very few cases, driveability problems may be caused by the brand of gasoline you
are using. If driveability problems persist, try changing the brand of gasoline. If this
does not correct the problem, consult your Lexus dealer.
■Gasoline quality standards
●Automotive manufacturers in the US, Europe and Japan have developed a
specification for fuel quality called World-Wide Fuel Charter (WWFC) that is
expected to be applied worldwide.
●The WWFC consists of four categories that are based on required emission
levels. In the US, category 4 has been adopted.
●The WWFC improves air quality by lowering emissions in vehicle fleets, and
customer satisfaction through better performance.
■Lexus recommends the use of gasoline containing detergent additives
●Lexus recommends the use of gasoline that contains detergent additives to
avoid build-up of engine deposits.
●All gasoline sold in the US contains detergent additives to clean and/or keep
clean intake systems.
■Lexus recommends the use of cleaner burning gasoline
Cleaner burning gasoline, including reformulated gasoline that contains oxygen-
ates such as ethanol or MTBE (Methyl Tertiary Butyl Ether) is available in many
areas.
Lexus recommends the use of cleaner burning gasoline and appropriately blended
reformulated gasoline. These types of gasoline provide excellent vehicle perfor-
mance, reduce vehicle emissions and improve air quality.
■Lexus does not recommend blended gasoline
●Lexus allows the use of oxygenate blended gasoline where the oxygenate con-
tent is up to 10% ethanol or 15% MTBE.
●If you use gasohol in your Lexus, be sure that it has an octane rating no lower
than 87.
●Lexus DOES NOT recommend the use of gasoline containing methanol.
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565
Alphabetical index
IS350/250_U
Bluetooth® phone ............................... 284
Brake
Fluid .......................................................... 394
Parking brake ........................................148
Brake assist ...............................................185
Care Exterior ...................................................368
Interior....................................................... 371
Seat belts ................................................372
Cargo capacity ........................................ 191
Cargo hooks ...........................................347
CD changer ............................................ 227
CD player................................................. 227
Chains......................................................... 195
Child restraint system Booster seats, definition...................109
Booster seats, installation ..................116
Convertible seats, definition ..........109
Convertible seats, installation .........116
Front passenger occupant classification system .......................104
Infant seats, definition ........................109
Infant seats, installation........................116
Installing CRS with LATCH anchors ................................................... 114
Installing CRS with seat belts ..........116
Installing CRS with top straps .........119 Child safety
Airbag precautions ..............................99
Battery precautions ............ 398, 500
Child restraint system ....................... 109
Child-protectors ................................... 44
How your child should wear
the seat belt .......................................... 63
Installing child restraints..................... 113
Moon roof precautions....................... 81
Power window lock switch .............. 75
Power window precautions .............77
Removed electronic key
battery precautions ....................... 422
Seat belt comfort guide .......................61
Seat belt extender precautions......65
Seat belt precautions .......................... 64
Seat heater precautions..... 337, 340
Trunk precautions................................. 49
Child-protectors ...................................... 44
Cigarette lighter....................................333
Cleaning Exterior................................................... 368
Interior .......................................................371
Seat belts ................................................ 372
Clock .........................................................328
Coat hooks ..............................................345
Compass ..................................................356
Condenser .............................................. 394
Console box ...........................................320
Cooling system Engine overheating............................ 501
Cornering assist sensors .....................179
C