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■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
Electronic key battery
Replace the battery with a new one if it is discharged.
■You will need th e following items:
● Flathead screwdriver
● Small Phillips-head screwdriver
● Lithium battery (CR1632)
■ Replacing the battery
Take out the mechanical key.
Remove the cover.
Remove the depleted battery.
Insert a new battery with the “+”
terminal facing up.
STEP1
STEP2
STEP3
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■If the electronic key battery is discharged
The following symptoms may occur.
●The smart access system with push-button start and wireless remote control will
not function properly.
●The operational range is reduced.
■Use a CR1632 lithium battery
●Batteries can be purchased at your Lexus dealer, jewelers, or camera stores.
●Replace only with the same or equivalent type recommended by a Lexus dealer.
●Dispose of used batteries according to the local laws.
■When the card key battery needs to be replaced (if equipped)
The battery for the card key is available only at Lexus dealers. Your Lexus dealer
can replace the battery for you.
CAUTION
■Removed battery and other parts
These parts are small and if swallowed by a child, they can cause choking. Keep
away from children. Failure to do so could result in death or serious injury.
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents.
●Always work with dry hands.
Moisture may cause the battery to rust.
●Do not touch or move any other components inside the remote control.
●Do not bend either of the battery terminals.
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4
Maintenance and care
IS250C/350C_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. 4 1 8 )
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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Driver's side instrument panelRemove the lid.
Passenger's side instrument panel Remove the lid.
Tr u n k Remove the lid.
After a system failure, see “Fuse layout and amperage ratings”
(→ P. 455) for details about which fuse to check.
STEP4
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Maintenance and care
IS250C/350C_U
Remove the fuse with the pull-
out tool.
Check if the fuse has blown.
Ty p e A
Normal fuse
Blown fuse
Replace it with one of an appro-
priate amperage rating. The
amperage rating can be found
on the fuse box lid.
Ty p e BNormal fuse
Blown fuse
Replace it with one of an appro-
priate amperage rating. The
amperage rating can be found
on the fuse box lid.
STEP5
STEP6
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Removing the front controller (engine compartment: type B fuse box)
Lift the lid off while pushing the
tabs on either side.
Ty p e C Normal fuse
Blown fuse
Contact your Lexus dealer.
Ty p e DNormal fuse
Blown fuse
Contact your Lexus dealer.
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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