Page 486 of 628
4727-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
Flathead screwdriver
Small flathead screwdriver
Lithium battery CR2032
Take out the mechanical key.
Remove the cover.
To prevent damage to the key, wrap
the tip of the screwdriver with tape.
Remove the battery cover.
To prevent damage to the key, wrap
the tip of the screwdriver with tape.
Electronic key battery
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
1
2
3
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4737-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
Remove the depleted battery.
Insert a new battery with the “+” ter-
minal facing up.
Use a CR2032 lithium battery
Batteries can be purchased at any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional, local electrical appliance
shops or camera stores.
Replace only with the same or equivalent type recommended by the manufac-
turer.
Dispose of used batteries according to 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.
If the electronic key battery is depleted
The following symptoms may occur:
The smart entry & start system and wireless remote control will not function
properly.
The operational range will be reduced.
Certification for the key battery
Replace only with the same or equivalent type recommended by the manufac-
turer.
Dispose of used batteries according to local laws.
4
Page 488 of 628
4747-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
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.
Lithium battery precautions
RISK OF EXPLOSION IF BATTERY IS REPLACED BY AN INCORRECT
TYPE.
DISPOSE OF USED BATTERIES ACCORDING TO THE INSTRUCTIONS
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 component inside the remote control.
Do not bend either of the battery terminals.
Page 489 of 628
4757-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
Turn the power switch off.
Open the fuse box cover.
Engine compartment:
Remove the clips.
Push the tabs on either side to
detach the lock and lift the lid off
while pulling the lock plate.
When installing the lid, check that
the lock plate and the tabs on
either side are connected cor-
rectly.
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.
1
2
Page 490 of 628
4767-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
Left side instrument panel (left-hand drive vehicles)
Remove the lid.
Left side instrument panel (right-hand drive vehicles)
Remove the lid.
Remove the fuse with the pullout
tool.
Only type A fuses can be removed
using the pullout tool.
3
Page 491 of 628
4777-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
Check if the fuse is blown.
Normal fuse
Blown fuse
Type A and B:
Replace the blown fuse with a new fuse of an appropriate amperage rating.
The amperage rating can be found on the fuse box lid.
Ty p e C a n d D :
Contact any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
4
1
2
Ty p e ATy p e B
Ty p e CTy p e D
Page 492 of 628

4787-3. Do-it-yourself maintenance
IS300h_EE(OM53B95E)
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. 479)
If the replaced fuse blows again, have the vehicle inspected by any authorized
Lexus dealer or repairer, or another duly qualified and equipped professional.
If there is an overload in a circuit
The fuses are designed to blow, protecting the wiring harness from damage.
When replacing light bulbs
Lexus recommends that you use genuine Lexus products designed for this vehi-
cle. Because certain bulbs are connected to circuits designed to prevent overload,
non-genuine parts or parts not designed for this vehicle may be unusable.
CAUTION
To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failure to do so may cause damage to the vehicle, and possibly a fire or injury.
Never use a fuse of a higher amperage rating than that indicated, or use any
other object in place of a fuse.
Always use a genuine Lexus fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
Do not modify the fuses or fuse boxes.
Fuse box near the power control unit
Never check or replace the fuses as there are high voltage parts and wiring near
the fuse box.
Doing so may cause electric shock, resulting in death or serious injury.
NOTICE
Before replacing fuses
Have the cause of electrical overload determined and repaired by any autho-
rized Lexus dealer or repairer, or another duly qualified and equipped profes-
sional as soon as possible.
Page 493 of 628
4797-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53B95E)
Check the wattage of the light bulb to be replaced. (P. 572)
Front
Vehicles with discharge headlights
Light bulbs
You may replace the following bulbs by yourself. The difficulty level of
replacement varies depending on the bulb. As there is a danger that com-
ponents may be damaged, we recommend that replacement is carried out
by any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
Preparing for light bulb replacement
Bulb locations
Front turn signal light
Halogen front fog light (if equipped)1
2