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When trouble arises
489
5-1. Essential information
IS250C/350C_U
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temperature gauge needle continually points
higher than normal
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the engine
■ Operational symptoms
●Engine missing, stumbling or running rough
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, sp ongy feeling, pedal almost touches
the floor
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5-1. Essential information
IS250C/350C_U
Fuel pump shut off system
NOTICE
■Before starting the engine
Inspect the ground under the vehicle.
If you find that fuel has leaked on to the ground, the fuel system has been damaged
and is in need of repair. Do not restart the engine.
To minimize the risk of fuel leakage when the engine stalls or an airbag
inflates upon collision, the fuel pump shut off system stops supplying fuel to
the engine.
Follow the procedure below to restart the engine after the system is
activated.
Turn the “ENGINE START STOP” switch to the ACCESSORY
mode or OFF.
Restart the engine.
STEP1
STEP2
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492
5-2. Steps to take in an emergency
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.
The warning light will operate as follows, even when the sys-
tem is not malfunctioning:
• The light will flash quickly when the system is operating. (→ P. 222)
• The light will flash when the pre-collision braking is dis-
abled. ( →P. 223)
• The light will flash when the system cannot temporarily be used. ( →P. 5 0 3 )
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5-2. Steps to take in an emergency
IS250C/350C_U
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire (vehicles with a spare tire)
The compact spare tire is not equipped with the tire pressure warning valve and
transmitter. If a tire goes flat, the tire pressure warning light will not turn off even
though the flat tire is replaced with the spare tire. Replace the spare tire with the
repaired tire and adjust the proper tire inflation pressure. The tire pressure warning
light will turn off after a few minutes.
■If the tire pressure warning system is inoperative
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer
●If a different set of tires has been selected using the satellite switch.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby
●If a radio set at similar frequencies is in use in the vehicle
●If there is a lot of snow or ice on the vehicle, in particular around the wheels or
wheel housings
●If non-genuine Lexus wheels are used (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used
■If the tire pressure warning light frequently comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute
when the “ENGINE START STOP” switch is turned to IGNITION ON mode, have
it checked by your Lexus dealer.
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5-2. Steps to take in an emergency
IS250C/350C_U
If a warning message is displayed
Stop the vehicle immediately.
A buzzer sounds and a warning message is shown on the multi-informa-
tion display. The following warnings indicate 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.
MessageDetails
(U.S.A)
(Canada) (Flashing)Indicates an abnormal engine oil pressure.The warning light may turn on if the engine oil pres-
sure is too low.
If a warning is shown on the multi-information display, stay calm and per-
form the following actions:
Master warning light
The master warning light also
comes on or flashes in order to
indicate that a message is cur-
rently being displayed on the
multi-information display.
Multi-information display
If any of the warning lights turns on again after performing the follow-
ing actions, contact your Lexus dealer.
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504
5-2. Steps to take in an emergency
IS250C/350C_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.
The vehicle was driven
with the retractable hard-
top partially open.
When the vehicle speed
exceeds 1.6 mph
(3 km/h), flashes
and a buzzer will sound.
Stop the vehicle in a safe
place and open or close
the retractable hardtop
completely. ( →P. 8 6 )
(Flashing)
The “ENGINE START
STOP” switch was turned
off while the retractable
hardtop was partially
open.
Open or close the retract-
able hardtop completely.
(→ P. 8 6 )
MessageDetailsCorrection procedure
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When trouble arises
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5-2. Steps to take in an emergency
IS250C/350C_U
• The roof switch was operated when there
was an obstacle behind
the vehicle.
•Operation of the retractable hardtop was
suspended due to an
obstacle being detected
behind the vehicle.
When the roof switch is
pressed again within two
seconds of message
being displayed, message will be displayed.
(→ P. 8 6 )
The roof switch was
pressed while the trunk lid
was open.
Close the trunk lid.
The roof switch was
pressed while the trunk lid
opener main switch was
turned off.
Turn the trunk lid opener
main switch on. ( →P. 5 1 )
The roof switch was
pressed while the vehicle
was moving.
(→ P. 8 6 )
The roof switch was
pressed while there was
not enough power.
Start the engine
MessageDetailsCorrection procedure
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5-2. Steps to take in an emergency
IS250C/350C_U
The roof switch was
pressed while the lug-
gage cover was not in the
correct position.
(→ P. 8 6 )
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.
Indicates that engine oil
level is low.Check the level of engine
oil, and add if necessary.
MessageDetailsCorrection procedure