Page 451 of 586

450
4-3. Do-it-yourself maintenance
10_IS250C/350C_U
CAUTION
■Replacing light bulbs
●Turn off the lights. Do not attempt to replace the bulb immediately after turning
off the lights.
The bulbs become very hot and may cause burns.
●Do not touch the glass portion of the light bulb with bare hands. Hold the bulb by
the plastic or metal portion.
If the bulb is scratched or dropped it may blow out or crack.
●Fully install light bulbs and any parts used to secure them. Failing to do so may
result in heat damage, fire, or water entering the headlight unit. This may damage
the headlights or cause condensation to build up on the lens.
●Do not attempt to take apart or repair the low beam headlight bulbs, connectors,
power supply circuits, or related components.
Doing so could result in electric shock and serious injury or death.
■Discharge headlights (if equipped)
●Contact your Lexus dealer before replacing discharge headlights (including light
bulbs).
●Do not touch the high-intensity discharge headlight’s high voltage socket when
the headlights are turned on.
An extremely high voltage of 20000 V will be discharged and could result in
serious injury or death by electric shock.
■To prevent damage or fire
Make sure bulbs are fully seated and locked.
Page 452 of 586

When trouble arises5
451
10_IS250C/350C_U
5-1. Essential informationEmergency flashers............... 452
If your vehicle needs to be towed................................. 453
If you think something is wrong .................................. 459
Fuel pump shut off system.... 460
Event data recorder ............... 461 5-2. Steps to take in an
emergency
If a warning light turns on or a warning buzzer
sounds... ................................. 463
If a warning message is displayed ............................ 472
If you have a flat tire (vehicles with standard
tires) ........................................ 486
If you have a flat tire (vehicles with run-flat
tires) ........................................ 495
If the engine will not start ..... 497
If the shift lever cannot be shifted from P ................. 499
If you lose your keys .............. 500
If the electronic key does not operate properly........... 501
If the vehicle battery is discharged......................... 506
If your vehicle overheats ..... 509
If the vehicle becomes stuck......................................... 512
If the retractable hardtop does not close ....... 514
Page 453 of 586
452
10_IS250C/350C_U
5-1. Essential information
Emergency flashers
NOTICE
■To prevent battery discharge
Do not leave the emergency flashers on longer than necessary when the engine is
not running.
Use the emergency flashers if the vehicle malfunctions or is involved in an
accident.
Press the switch to flash all the
turn signal lights. To turn them
off, press the switch once again.
Page 464 of 586

5
When trouble arises
463
10_IS250C/350C_U
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer sounds...
Stop the vehicle immediately. Continuing to drive the vehicle may be dangerous.
The following warning indicates a possible problem in the brake system.
Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
*: Parking brake engaged warning buzzer
→P. 4 7 5
Stop the vehicle immediately.
The following warning indicates the possibility of damage to the vehicle
that may lead to an accident. Immediately stop the vehicle in a safe place
and contact your Lexus dealer.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Brake system warning light (warning buzzer)*
• Low brake fluid
• Malfunction in the brake booster system This light also comes on when the parking brake is not
released. If the light turns off after the parking brake is fully
released the system is operating normally.
Warning lightWarning light/Details
Charging system warning lightIndicates a malfunction in the vehicle’s charging system.
Calmly perform the following actions if any of the warning lights turn on or
flash. If a light turns on or flashes, but then turns off, this does not necessar-
ily indicate a malfunction in the system.
Page 465 of 586

464
5-2. Steps to take in an emergency
10_IS250C/350C_U
Have the vehicle inspected by your Lexus dealer immediately.Failing to investigate the cause of the following warnings may lead to the
system operating abnormally and possibly cause an accident. Have the
vehicle inspected by your Lexus dealer immediately.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The electronic engine control system;
• The electronic throttle control system; or
• The electronic automatic transmission control system.
SRS warning lightIndicates a malfunction in:
• The SRS airbag system; or
• The seat belt pretensioner system.
(U.S.A.)
(Canada)
“ABS” warning lightIndicates a malfunction in:
•The ABS;
• The brake assist system.
Electric power steering system warning lightIndicates a malfunction in the EPS (Electric Power Steering)
system.
Pre-collision system warning light (if equipped)Indicates a malfunction in the pre-collision system.
Page 466 of 586

5
When trouble arises
465
5-2. Steps to take in an emergency
10_IS250C/350C_U
Follow the correction procedures.After taking the specified steps to co rrect the suspected problem, check
that the warning light turns off.
Warning lightWarning light/DetailsCorrection procedure
Open door warning light
(warning buzzer)
*1
Indicates that a door or the
trunk is not fully closed.
Check that both side doors
and the trunk are closed.
Low fuel level warning light
Remaining fuel
(Approximately 2.9 gal. [11 L,
2.4 Imp. gal.] or less)
Refuel the vehicle.
(On the instru-
ment cluster)
Driver’s seat belt reminder
light (warning buzzer)
*2
Warns the driver to fasten
his/her seat belt.Fasten the seat belt.
(On the center panel)
Front passenger’s seat belt
reminder light
(warning buzzer)
*2
Warns the front passenger to
fasten his/her seat belt.
Fasten the seat belt.
Tire pressure warning light
When the light comes on:
Low tire inflation pressureAdjust the tire inflation pres-
sure.
When the light comes on after
blinking for 1 minute:
Malfunction in the tire pres-
sure warning system
Have the system checked by
your Lexus dealer.
Page 467 of 586
466
5-2. Steps to take in an emergency
10_IS250C/350C_U
*1:Open door warning buzzer
→P. 4 7 5
*2:Driver's and front passenger’s seat belt reminders buzzer
The driver’s and front passenger’s seat belts reminder sounds to alert the driver
and front passenger that his or her seat belt is not fastened. The buzzer sounds
intermittently for 10 seconds after the vehicle has reached a speed of at least 12
mph (20 km/h). Then, if the seat belt is still unfastened, the buzzer will sound in a
different tone for 20 more seconds.
Warning lightWarning light/DetailsCorrection procedure
Master warning light
A buzzer sounds and the
warning light comes on and
flashes to indicate that the
master warning system has
detected a malfunction.
→ P. 4 7 2
Page 468 of 586

5
When trouble arises
467
5-2. Steps to take in an emergency
10_IS250C/350C_U
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The lamp will go off after taking several driving trips.
If the lamp does not go off even after several trips, contact your Lexus dealer as
soon as possible.
■Electric power steering warning light
When the battery is low or when the voltage drops temporarily, the electric power
steering warning light may come on.
■Front passenger detection sensor and pass enger seat belt reminder and warning
buzzer
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash and the warning buzzer to sound,
even if a passenger is not sitting in the seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pressing the
satellite switch does not turn off the tire pressure warning light.