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4-3. Do-it-yourself maintenance
4
Maintenance and care
08_IS350/250_U_(L/O_0708)
Fuse layout and amperage ratings■ Engine compartment (type A)
FuseAmpereCircuit
1ABS NO.325 AVDIM
2PWR HTR25 A
3TURN-HAZ15 AEmergency flashers, turn signals
4IG2 MAIN20 AIG2, IGN, GAUGE
5RAD NO.230 AAudio
6D/C CUT20 ADOME, MPX-B
7RAD NO.130 AAudio
8MPX-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, security sys-
tem
9DOME10 AInterior lights, meter
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4-3. Do-it-yourself maintenance
08_IS350/250_U_(L/O_0708)
FuseAmpereCircuit
10E/G-B60 AFR CTRL-B, ETCS, ALT-S, steering
lock system, exhaust system
11DIESEL GLW80 A
12ABS150 AVSC, VDIM
13RH J/B-B30 APower door lock system, smart access
system with push-button start
14MAIN30 AHeadlight low beams
15STARTER30 ASmart access system with push-button
start
16LH J/B-B30 APower door lock system, SECURITY
17P/ I - B60 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
18EPS80 APo w e r s t e e r i n g
19ALT150 A
LH J/B-AM, E/G-AM, GLW PLG2,
HEATER, FAN1, FAN2, DEFOG,
ABS2, RH J/B-AM, GLW PLG1,
LH J/B-B, RH J/B-B
20GLW PLG150 APTC heater
21RH 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
22ABS230 AVSC
23DEFOG50 ARear window defogger
24FA N 240 AElectric cooling fans
25FA N 140 AElectric cooling fans
26HEATER50 AAir conditioning system
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4-3. Do-it-yourself maintenance
4
Maintenance and care
08_IS350/250_U_(L/O_0708)
FuseAmpereCircuit
14RR DOOR LH20 APo w e r w i n d o w s
15FR DOOR LH20 APo w e r w i n d o w s
16SECURITY7. 5 ASmart access system with push-button
start
17H-LP LVL7. 5 AAFS
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, sun shade, seat belts,
Intuitive parking assist, cruise control,
air conditioning system, PTC heater
19FR WIP30 AWindshield wipers
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4-3. Do-it-yourself maintenance
4
Maintenance and care
08_IS350/250_U_(L/O_0708)
FuseAmpereCircuit
13FR DOOR RH20 APo 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
14AM215 ASmart access system with push-button
start
15RH-IG7. 5 A
Seat belts, intuitive parking assist,
automatic transmission, seat heater
and ventilator
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, VSC,
air conditioning system, pre-collision
seat belt, electric tilt and telescopic
steering, power windows, navigation
system
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may
need replacement. (
→P. 3 4 2 )
●If the replaced fuse blows again, have the vehicle inspected by your Lexus
dealer.
■If there is an overload in the circuits
The fuses are designed to blow before the entire wiring harness is damaged.
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5-2. Steps to take in an emergency
08_IS350/250_U_(L/O_0708)
If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk and key linked functions
Doors
Remove the cover on the driver’s
door handle using the mechanical
key in order to perform the follow-
ing operations.
Locks all doors
Closes the windows/moon roof
(turn and hold)
Unlocks the door
Turning the key rearward unlocks
the driver's door. Turning the key
once again unlocks the other
doors.
Opens the windows/moon roof
(turn and hold)
Return the cover to the original
position after use.
If communication between the electronic key and vehicle is interrupted
(
→P. 26) or the electronic key cann ot be used because the battery is
depleted, the smart access system with push-button start and wireless
remote control cannot be used. In such cases, the doors and trunk can be
opened or the engine can be started by following the procedure below.
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5-2. Steps to take in an emergency
08_IS350/250_U_(L/O_0708)
■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.
■When the battery is removed or discharged
The power windows must be initialized.
(→ P. 6 4 )
CAUTION
■Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable
gas that may be emitted from the battery.
●Make sure the jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any part other than the intended terminal.
●Do not allow the jumper cables to come into contact with the “+” and “-” termi-
nals.
●Do not allow open flame or use matches, cigarette lighters or smoke near the
battery.
Maintain the engine speed on 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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6-1. Specifications
6
Vehicle specifications
08_IS350/250_U_(L/O_0708)■
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. 109.
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
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Alphabetical index
08_IS350/250_U_(L/O_0708)
Bottle holders .......................................... 241
BrakeFluid ............................................................301
Parking brake ........................................ 129
Brake assist ............................................... 170
Care Exterior ....................................................274
Interior...................................................... 277
Seat belts ............................................... 278
Cargo capacity ....................................... 179
Cargo hooks ............................................ 261
CD changer ...............................................211
CD player....................................................211
Chains.........................................................183
Child restraint system Booster seats, definition.................... 95
Booster seats, installation ................. 99
Convertible seats, definition ........... 95
Convertible seats, installation ........ 99
Front passenger occupant classification system ........................ 90
Infant seats, definition ......................... 95
Infant seats, installation....................... 99
Installing CRS with lower anchorages ......................................... 102
Installing CRS with seatbelts .......... 99
Installing CRS with top straps .......103 Child safety
Airbag precautions ............................. 85
Battery precautions ............. 304, 399
Child restraint system .........................95
Child-protectors ...................................38
How your child should wear
the seatbelt............................................55
Installing child restraints.....................98
Moon roof precautions......................68
Power window lock switch .............. 64
Power window precautions ............65
Removed electronic key battery
precautions........................................326
Seat belt comfort guide ..................... 53
Seat belt extender precautions...... 57
Seat belt precautions ..........................56
Seat heater precautions......252, 254
Trunk precautions................................. 43
Child-protectors ......................................38
Cigarette lighter.................................... 249
Cleaning Exterior.................................................... 274
Interior ..................................................... 277
Seat belts ................................................278
Clock ......................................................... 244
Coat hooks ..............................................259
Compass .................................................. 269
Condenser ............................................... 301
Console box ........................................... 237
Cooling system Engine overheating.......................... 400
Cornering assist sensors .................... 164
Cruise control Cruise control....................................... 152
Dynamic radar cruise control....... 155
C