
5077-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53D56E)
■Replacing the following bulbs
If any of the lights listed below has burnt out, have it replaced by any autho-
rized Lexus dealer or repairer, or another duly qualified and equipped profes-
sional.
●Headlights
●Front position lights and daytime running lights
●Side turn signal lights
●Front fog lights (if equipped)
●Stop/tail lights
●Tail lights
●Rear fog light
●High mounted stoplight
●License plate lights
■Discharge headlights (if equipped)
If voltage to the discharge bulbs is insufficient, the bulbs may not come on, or may go out
temporarily. The discharge bulbs will come on when normal power is restored.
■LED Lights
The lights other than the discharge headlights (if equipped), front turn signal lights, rear
turn signal lights, back-up light and outer foot lights each consist of a number of LEDs. If
any of the LEDs burn out, take your vehicle to any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional to have the light replaced.
■Condensation build-up on the inside of the lens
Temporary condensation build-up on the inside of the headlight lens does not indicate a
malfunction. Contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional for more information in the following situations:
●Large drops of water have built up on the inside of the lens.
●Water has built up inside the headlight.
■When replacing the front turn signal lights (vehicles with LED headlights)
When the washer fluid filler opening is remove d with a large amount of washer fluid con-
tained in the washer tank, washer fluid may spill onto the vehicle and cleaning may be
required.
■When replacing light bulbs
→ P. 4 9 4

5218-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
If a warning light turns on or a warning buzzer
sounds
Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, but then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspected by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
Brake system warning light (warning buzzer)*1
Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning
→ Immediately stop the vehicle in a safe place and contact any
authorized Lexus dealer or repairer, or another duly qualified
and equipped professional. Continuing to drive the vehicle may
be dangerous.
Brake system warning light
Indicates a malfunction in:
• The regenerative braking system; or
• The electronically controlled brake system
→ Have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional
immediately.
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
→ Immediately stop the vehicle in a safe place and contact any
authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
Malfunction indicator lamp
Indicates a malfunction in:
• The hybrid system;
• The emission control system (if equipped);
• The electronic engine control system; or
• The electronic throttle control system
→ Have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional
immediately.

5238-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
Automatic headlight leveling system warning lightIndicates a malfunction in the au tomatic headlight leveling system
→ Have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional
immediately.
Open door warning light (warning buzzer)*2
Indicates that a door or the trunk is not fully closed
→ Check that all the doors and the trunk are closed.
Low fuel level warning light
Indicates that remaining fuel is a pproximately 10 L (2.6 gal., 2.2 Imp.
gal.) or less
→ Refuel the vehicle.
Driver’s and front passenger’s seat belt reminder light (warning
buzzer)
*3
Warns the driver and/or front passenger to fasten their seat belts
→ Fasten the seat belt.
If the front passenger’s seat is occupied, the front passenger’s
seat belt also needs to be fastened to make the warning light
(warning buzzer) turn off.
Rear passengers’ seat belt reminder lights (warning buzzer)*3
Warns the rear passengers to fasten their seat belts
→ Fasten the seat belt.
Master warning light
A buzzer sounds and the warning light comes on and flashes to
indicate that the master warning system has detected a malfunc-
tion.
→ P. 5 2 7
Tire pressure warning light
When the light comes on:
Low tire inflation pressure such as
• Natural causes ( →P. 5 2 4 )
• Flat tire ( →P. 545, 559)
→ Adjust the tire inflation pre ssure to the specified level.
The light will turn off after a few minutes. In case the light does
not turn off even if the tire inflation pressure is adjusted, have the
system checked by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
When the light comes on af ter blinking for 1 minute:
Malfunction in the tire pressure warning system
→ Have the system checked by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
Warning lightWarning light/Details/Actions

5348-2. Steps to take in an emergency
IS300h_EE(OM53D56E)
Indicates that the hybrid system was stopped while driv-
ingA buzzer also sounds.
→ Operate the steering wheel with more force than
usual.
Indicates that the power switch is turned off or turned to
ACCESSORY mode and the driver’s door is opened
while the lights are turned on
A buzzer also sounds.
→ Turn the lights off.
(If equipped)
Indicates that the moon roof is not fully closed (with the
power switch off, and the driver’s door open)
A buzzer also sounds.
→ Close the moon roof.
Indicates that the windows are not fully closed (with the
power switch off, and the driver’s door open)
A buzzer also sounds.
→ Close all the windows.
(If equipped)
Indicates that the windows and the moon roof are not
fully closed (with the power switch off, and the driver’s
door open)
A buzzer also sounds.
→ Close all the windows and the moon roof.
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)
(Flashes)
(Flashes)
(Flashes)

5368-2. Steps to take in an emergency
IS300h_EE(OM53D56E)
Indicates that remaining fuel is approximately 10 L (2.6
gal., 2.2 Imp. gal.) or less
→Refuel the vehicle.
Indicates that the TRC (Tr action Control) system has
been deactivated
→ Tu r n t h e T R C o n . ( →P. 2 9 8 )
Indicates that the engine oil is scheduled to be changed.
(The indicator will not work properly unless the message
has been reset.)
→ Check the engine oil, and change if necessary.
After changing the engine oil, the message should
be reset.
Indicates that the engine oil should be changed. (After
the engine oil is changed and the message has been
reset.)
→Check and change the engine oil, and oil filter by
any authorized Lexus dealer or repairer, or another
duly qualified and equipped professional. After
changing the engine oil, the message should be
reset.
(If equipped)
Indicates that the Automatic High Beam switch is
pressed while the headlights are in low beam.
→ Turn the high beam on and press the Automatic
High Beam switch again.
(If equipped)
Indicates that, since the VSC (Vehicle Stability Control)
system was turned off, the pre-crash brake system oper-
ation is stopped
→Tu r n t h e V S C o n . ( →P. 2 9 8 )
(If equipped)
Indicates that the PCS (Pre-Crash Safety system) is not
currently functional because the grille cover or the sen-
sor is dirty
→ Check the grille cover and the sensor and clean
them if they are dirty.
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)

624Alphabetical index
IS300h_EE(OM53D56E)
Outside rear view mirror switches.................................................. 181
Paddle shift switches .......................... 221
PCS OFF switch ................................303
Power door lock switch ...................139
Power switch ......................................... 212
Power window switches ................. 185
Rear sunshade switch...................... 437
Rear window and outside rear view mirror defoggers
switch..................................................... 418
Seat heater switches ........................ 424
Seat ventilator switches .................. 424
Snow mode switch ........................... 220
Talk switch ...............................................391
Telephone switches............................391
Tilt and telescopic steering control switch ..................................... 177
Tire pressure warning reset switch....................................................469
Trunk opener main switch ..............145
Trunk opener switch ..........................143
Vehicle-to-vehicle distance button ...................................................258
VSC OFF switch ...............................298
Window lock switch.......................... 185
Windshield wiper de-icer switch......................................................419
Windshield wiper and washer switch ......................... 238 Tachometer ............................................. 109
Tachometer settings .............................. 117
Tail lights................................................... 229
Light switch............................................229
Replacing light bulbs ....................... 507
Talk switch .................................................391
Telephone switches ...............................391
Theft deterrent system Alarm .......................................................... 96
Double locking system...................... 95
Immobilizer system ............................. 90
Intrusion sensor and tilt sensor...... 99
Tire inflation pressure ......................... 482
Maintenance data .............................586
Tire inflation pressure display function ............................................... 468
Warning light....................................... 523
Tire pressure warning system ......... 468 Function.................................................. 468
Initializing ............................................... 468
Installing tire pressure warning
valves and transmitters ............... 468
Registering ID codes....................... 469
Tire pressure warning reset switch ................................................... 469
Warning light....................................... 523T