Page 462 of 626
461
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS250C/350C_U
10ECU-IG LH10 A
Cruise control, air conditioning sys-
tem, power steering, rain sensor, anti-
glare inside rear view mirror, shift lock
system, tire inflation pressure warning
system, vehicle stability control
11FR S/HTR LH15 ASeat heaters and ventilators, air condi-
tioning system
12FR DOOR LH20 APower windows, outside rear view
mirrors
13SECURITY7. 5 ASmart access system with push-button
start
14H-LP LVL7. 5 AAutomatic head light leveling system
15LH-IG10 A
Charging system, headlight cleaner,
rear window defogger, electric cool-
ing fans, emergency flashers, turn sig-
nal lights, back-up lights, stop lights,
mirror heaters, seat belt pretensioner,
intuitive parking assist, cruise control,
PTC heater, exhaust system, smart
access system with push-button start
16FR WIP30 AWindshield wipers
FuseAmpereCircuit
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4-3. Do-it-yourself maintenance
4
Maintenance and care
IS250C/350C_U
10CIG15 ACigarette lighter
11PWR OUTLET15 APo w e r o u t l e t
12FR DOOR RH20 APo w e r w i n d o w s , o u t s i d e r e a r v i e w
mirrors
13AM27. 5 AStarting system
14RH-IG7. 5 A
Seat belt pretensioner, intuitive park-
ing assist, automatic transmission, seat
heater and ventilator
15FR S/HTR RH15 ASeat heaters and ventilators, air condi-
tioning system
16ECU-IG RH10 A
Power seats, headlights, front fog
lights, parking lights, license plate
lights, front side marker lights, wind-
shield washer, outside rear view mir-
rors, VDIM, air conditioning system,
pre-collision seat belt, electric tilt and
telescopic steering, power windows,
navigation system, vehicle stability
control, retractable hardtop, clock
FuseAmpereCircuit
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4-3. Do-it-yourself maintenance
IS250C/350C_U■
Tr u n k
FuseAmpereCircuit
1DEFOG30 ARear window defogger
2ROOF RH30 ARetractable hardtop
3ROOF LH30 ARetractable hardtop
4LGG RH30 ARetractable hardtop
5LGG LH30 ARetractable hardtop
6LGG LCK RH30 ARetractable hardtop
7LGG LCK LH30 ARetractable hardtop
8P-T R AY M A I N30 ARetractable hardtop
9P-T R AY S I D E7. 5 ARetractable hardtop
10PSB30 APre-collision seat belt
■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 6 8 )
●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, protecting the wiring harness from damage.
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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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When trouble arises
493
5-2. Steps to take in an emergency
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.
Slip indicator
Indicates a malfunction in:
• The VSC system;
• The TRAC system; or
• The hill-start assist control 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 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.
Warning lightWarning light/Details
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494
5-2. Steps to take in an emergency
IS250C/350C_U
*1: Open door warning buzzer
→P. 5 0 3
*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.
Tire pressure warning light
When the light comes on:
Low tire inflation pressure
such as
• Natural causes (→ P. 4 9 6 )
• Flat tire ( →P. 513, 522)
Adjust the tire inflation pres-
sure 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 your Lexus
dealer.
When the light comes on after
blinking for 1 minute:
Malfunction in the tire pres-
sure warning system
(→ P. 4 9 6 )
Have the system checked by
your Lexus dealer.
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. 5 0 0
Warning lightWarning light/DetailsCorrection procedure
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5
When trouble arises
495
5-2. Steps to take in an emergency
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 system warning light
When the voltage is low or drops, the electric power steering system 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.
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5
When trouble arises
535
5-2. Steps to take in an emergency
IS250C/350C_U
NOTICE
■To prevent damaging the vehicle
Do not pull- or push-start the vehicle, because the three-way catalytic converter
may overheat and become a fire hazard.
■When handling jumper cables
Be careful that the jumper cables do not become tangled in the cooling fan or any
of the belts when connecting or disconnecting them.