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432
4-3. Do-it-yourself maintenance
IS350/250_U
■Checking interval
Inspect and replace the air conditioning filter according to the maintenance sched-
ule. In dusty areas or areas with heavy traffic flow, early replacement may be
required. (For scheduled maintenance information, please refer to the “Owner's
Manual Supplement/Scheduled Maintenance”.)
■If air flow from the vents decreases dramatically
The filter may be clogged. Check the filter and replace if necessary.
■Cleaning method
If the filter is dirty, clean by blow-
ing compressed air through the
filter from the downward side.
Hold the air gun 2 in. (5 cm)
from the filter and blow for
approximately 2 minutes at
72 psi (500 kPa, 5.0 kgf/cm
2
or bar).
If it is not available, have the
filter cleaned by your Lexus
dealer.
■ Replacement method
Remove the air conditioning fil-
ter from the filter case and
replace it with a new one.
The “↑UP” marks shown on the
filter and the filter case should
be pointing up.
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4-3. Do-it-yourself maintenance
IS350/250_U
FuseAmpereCircuit
13FR DOOR RH20 APower windows, outside rear view
mirrors
14AM27. 5 ASmart access system with push-button
start
15RH-IG7. 5 A
Seat belts, intuitive parking assist,
automatic transmission, seat heater
and ventilator
16FR S/HTR RH15 ASeat heaters and ventilators
17ECU-IG RH10 A
Power seats, smart access system with
push-button start, AWD system, out-
side rear view mirrors, VDIM, air con-
ditioning system, pre-collision seat
belt, electric tilt and telescopic steer-
ing, power windows, navigation sys-
tem
■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. 4 5 2 )
●If the replaced fuse blows again, have the vehicle inspected by your Lexus
dealer.
■If there is an overload in the circuits
The fuses are designed to blow before the entire wiring harness is damaged.
Page 469 of 578
468
5-1. Essential information
IS350/250_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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When trouble arises
469
5-1. Essential information
IS350/250_U
Event data recorder
In a crash or a near car crash eventThe SRS airbag sensor assembly contains the EDR. In a crash or a near
car crash event, this device may record some or all of the following infor-
mation:
● Engine speed
● Whether the brake pedal was applied or not
● Ve h i c l e s p e e d
● To what extent the accelerator pedal was depressed
● Position of the transmission shift lever
● Whether the driver and front passenger wore seat belts or not
● Driver's seat position
● SRS airbag deployment data
● SRS airbag system diagnostic data
● Front passenger’s occupant classification
The information above is intended to be used for the purpose of improv-
ing vehicle safety performance. Unlike general data recorders, the EDR
does not record sound data such as conversation between passengers.
Your vehicle has computers that monitor and control certain aspects of
your vehicle. These computers assist in driving and maintaining optimal
vehicle performance.
Besides storing data useful for troubleshooting, there is an event data
recorder (EDR) that records data in a crash or a near car crash event.
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472
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.
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5-2. Steps to take in an emergency
IS350/250_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/Details
(U.S.A.)
(Canada)
ABS warning light
Indicates 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.
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 all 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.
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5-2. Steps to take in an emergency
IS350/250_U
NOTICE
■Precaution when installing a different tire
When a tire of a different specification or maker is installed, the tire pressure warn-
ing system may not operate properly.
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5-2. Steps to take in an emergency
IS350/250_U
Have the vehicle inspected by your Lexus dealer immediately.
A buzzer sounds and a warning message is shown on the multi-informa-
tion display. 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.
Wa r n i n g m e s s a g eDetails
(If equipped)
Indicates a malfunction in the AWD system.
(Flashing)
Indicates a malfunction in the steering lock system.
(If equipped)
Indicates a malfunction in the pre-collision system.