Page 462 of 578
5
When trouble arises
461
IS350/250_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 3
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.
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 463 of 578

462
5-2. Steps to take in an emergency
IS350/250_U
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.
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
Charging system warning light Indicates a malfunction in the vehicle’s charging system.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Malfunction indicator lampIndicates 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 light
Indicates a malfunction in the EPS (Electric Power Steering)
system.
Page 468 of 578

5
When trouble arises
467
5-2. Steps to take in an emergency
IS350/250_U
CAUTION
■When the electric power steering warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, firmly hold and
operate it using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause loss of
vehicle control and result in death or serious injury.
●Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pres-
sure immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust-
ment, it is probable that you have a flat tire. Check the tires. If the tire is flat,
change to the spare tire and have the flat tire repaired by the nearest Lexus
dealer.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could
lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.
Page 475 of 578
474
5-2. Steps to take in an emergency
IS350/250_U
Indicates that the trunk is
not fully closed. flashes and a
buzzer sounds to indi-
cate that trunk is not fully
closed (with the vehicle
having reached a speed
of 3 mph [5 km/h]).
Close the trunk.
(Flashing)
(If equipped)
Indicates that the moon
roof is not fully closed
(with the “ENGINE
START STOP” switch
OFF and the driver’s
door opened).
Close the moon roof.
Indicates that the parking
brake is still engaged.
flashes and a
buzzer sounds to indi-
cate that the parking
brake is still engaged
(with the vehicle having
reached a speed of 3
mph [5 km/h]).
Release the parking
brake.
Indicates that the washer
fluid level is low.Add washer fluid.
Wa r n i n g m e s s a g eDetailsCorrection procedure
Page 480 of 578
5
When trouble arises
479
5-2. Steps to take in an emergency
IS350/250_U
Once
(Vehicles with an auto-matic transmission)
Indicates that a
door has been
opened or closed
and the “ENGINE
START STOP”
switch has been
switched twice to
ACCESSO RY
mode from OFF.
Press the
“ENGINE START
STOP” switch
while applying the
brakes.
Once
(Vehicles with a manual
transmission)
Indicates that a
door has been
opened or closed
and the “ENGINE
START STOP”
switch has been
switched twice to
ACCESSO RY
mode from OFF.
Press the
“ENGINE START
STOP” switch
while depressing
the clutch pedal.
(Flashing)
Indicates that the
steering lock has
not released
within 3 seconds
of pressing the
“ENGINE START
STOP” switch.Press the
“ENGINE START
STOP” switch
again while turn-
ing the steering
wheel with the
brake pedal
depressed.
InteriorbuzzerExterior buzzerWa r n i n g m e s s a g eDetailsCorrection
procedure
Page 482 of 578
5
When trouble arises
481
5-2. Steps to take in an emergency
IS350/250_U
If you have a flat tire
Remove the flat tire and replace it with the spare provided.
■Before jacking up the vehicle
●Stop the vehicle on a hard, flat surface.
● Set the parking brake.
● Shift the shift lever to P (vehicles with an automatic transmission)
or R (vehicles with a manual transmission).
● Stop the engine.
● Turn on the emergency flashers.
■ Location of the spare tire, jack and tools
Tool bag
(including towing eyelet) Jack
Jack handle
Spare tire
Ti g h t e nLoosen
Page 488 of 578

5
When trouble arises
487
5-2. Steps to take in an emergency
IS350/250_U
CAUTION
●Use a jack stand if it is necessary to get under the vehicle.
Take particular care when lowering the vehicle to ensure that no one working on or
near the vehicle may be injured.
■Replacing a flat tire
Observe the following precautions to reduce the risk of death or serious injury.
●Never use oil or grease on the wheel bolts or wheel nuts.
Oil and grease may cause the wheel nuts to be excessively tightened, leading to
bolt or disc wheel damage. In addition, the oil or grease can cause the wheel nuts
to loosen and the wheel may fall off, causing a serious accident. Remove any oil or
grease from the wheel bolts or wheel nuts.
●Have the wheel nuts tightened with a torque wrench to 76 ft•lbf (103 N•m, 10.5
kgf•m) as soon as possible after changing wheels.
Failure to follow these precautions could cause the nuts to loosen and the wheels
may fall off, which could lead to an accident causing death or serious injury.
■When using the spare tire
●Remember that your compact spare tire is specifically designed for use with your
vehicle. Do not use your compact spare tire on another vehicle.
●Do not use two compact spare tires simultaneously.
●Replace the compact spare tire with a standard tire as soon as possible.
●Avoid sudden acceleration, deceleration and braking, as well as sharp cornering.
■Speed limit when using the spare tire
Do not drive at speeds in excess of 50 mph (80 km/h) when a compact spare tire is
installed on the vehicle.
The compact spare tire is not designed for driving at high speeds. Failing to observe
this precaution may lead to an accident causing death or serious injury.
■When the spare tire is attached
The vehicle speed may not be correctly detected, and the following systems may
not operate correctly:
●ABS & brake assist
●VSC
●TRAC
Page 491 of 578
490
5-2. Steps to take in an emergency
IS350/250_U
Emergency start function
When the engine does not start, the following steps can be used as an
interim measure to start the engine if the “ENGINE START STOP” switch
is functioning normally.Vehicles with an automatic transmission Set the parking brake.
Put the shift lever in P.
Set the “ENGINE START STOP” switch to ACCESSORY mode.
Press and hold the “ENGINE START STOP” switch for about 15
seconds while depressing the brake pedal firmly.
Vehicles with a manual transmission Set the parking brake.
Put the shift lever in N.
Set the “ENGINE START STOP” switch to the ACCESSORY
mode.
Push and hold the “ENGINE ST ART STOP” switch for about 15
seconds while depressing the brake pedal and clutch pedal firmly.
Even if the engine can be started using the above steps, the system may
be malfunctioning. Have the vehicle checked by your Lexus dealer.
STEP1
STEP2
STEP3
STEP4
STEP1
STEP2
STEP3
STEP4