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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
Checking and replacing fuses
If any of the electrical components do not operate, a fuse may have blown.
If this happens, check and replace the fuses as necessary.
Turn the “ENGINE START STOP” switch OFF.
Engine compartment (type B fuse box): Remove the engine
compartment cover. ( →P. 388)
Open the fuse box cover.
Engine compartment (type A fuse box)
Push the tabs in and lift the lid
off.
Engine compartment (type B fuse box) Push the tabs in and lift the lid
off.STEP1
STEP2
STEP3
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4-3. Do-it-yourself maintenance
IS350/250_U
Removing the front controller (engine compartment: type B fuse box)
Lift the lid off while pushing the
tabs on either side.
Ty p e D Normal fuse
Blown fuse
Contact your Lexus dealer.
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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 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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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
Headlight aim
■Removing the engine compartment cover
→ P. 388
■ Vertical movement adjusting bolts
Adjustment bolt A
Adjustment bolt B
■ Before checking the headlight aim
Make sure the vehicle has a full tank of gas and the area around
the headlight is not deformed.
Park the vehicle on level ground.
Sit in the driver’s seat.
Bounce the vehicle several times.
STEP1
STEP2
STEP3
STEP4
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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
Light bulbs
You may replace the following bulbs yourself. For more information about
replacing other light bulbs, contact your Lexus dealer.
■Preparing a replacement light bulb
Check the wattage of the light bulb being replaced. ( →P. 5 2 4 )
■ Removing the engine compartment cover
→ P. 388
■ Front bulb locations
Parking lights (vehicles with
halogen headlights)
Headlight high beam and daytimerunning lights (vehicles with halogen headlights)
Headlight high beam
(vehicles with discharge
headlights)
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498
5-2. Steps to take in an emergency
IS350/250_U
If the vehicle battery is discharged
The following procedures may be used to start the engine if the vehicle’s
battery is discharged.
You can call your Lexus dealer or a qualified repair shop.
If you have a set of jumper (or booster) cables and a second vehicle
with a 12-volt battery, you can jump start your Lexus following the steps
below.
Remove the engine compartment covers. ( →P. 388)
Connecting the jumper cables.
Positive (+) battery terminal on your vehicle
Positive (+) battery terminal on the second vehicle
Negative (-) battery terminal on the second vehicle
Connect the jumper cable to ground on your vehicle as shown in the
illustration. Start the engine of the second vehicle. Increase the engine
speed slightly and maintain at that level for approximately 5
minutes to recharge the battery of your vehicle.
Open and close any of the doors with the “ENGINE START
STOP” switch OFF.
STEP1
STEP2
STEP3
STEP4
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When trouble arises
501
5-2. Steps to take in an emergency
IS350/250_U
If your vehicle overheats
If your engine overheats:
Stop the vehicle in a safe place and turn off the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: Stop the engine. Carefully lift the hood after the steam sub-
sides and then restart the engine.
If you do not see steam: Leave the engine running and carefully lift the hood.
Remove the engine compartment cover. ( →P. 388)
Check to see if the cooling fans are operating.
If the fans are operating: Wait until the temperature of the engine (shown on the
instrument cluster) begins to fall and then stop the engine.
If the fans are not operating: Stop the engine immediately and call your local Lexus
dealer.
After the engine has cooled
down sufficiently, check the
engine coolant level and inspect
the radiator core (radiator) for
any leaks.STEP1
STEP2
STEP3
STEP4
STEP5