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440
4-3. Do-it-yourself maintenance
10_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. 444)
●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 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
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5
When trouble arises
469
5-2. Steps to take in an emergency
10_IS250C/350C_U
■If the open retractable hardtop warning buzzer sounds
Immediately stop the vehicle in a safe place and open or close the retractable hard-
top fully.
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.Vehicles with run-flat tires
• Decelerate to the lowest appropriate speed as soon as possible. Do not drive over 50 mph (80 km/h).
• Check and adjust the tire inflation pressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, it is probable that you have a flat tire. Have the tire replaced 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.
Vehicles with standard tires
• Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, 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 586
474
5-2. Steps to take in an emergency
10_IS250C/350C_U
MessageDetails
(Flashing)
(If equipped)
Indicates a malfunction in the radar cruise control
system.
Indicates a malfunction in the retractable hardtop
system.
Page 477 of 586
476
5-2. Steps to take in an emergency
10_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 1 )
(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 1 )
MessageDetailsCorrection procedure
Page 478 of 586
5
When trouble arises
477
5-2. Steps to take in an emergency
10_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 1 )
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. 4 7 )
The roof switch was
pressed while the vehicle
was moving.
(→ P. 8 1 )
The roof switch was
pressed while there was
not enough power.
Start the engine
MessageDetailsCorrection procedure
Page 487 of 586
486
5-2. Steps to take in an emergency
10_IS250C/350C_U
If you have a flat tire (vehicles with standard tires)
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).
● Close the retractable hardtop. ( →P. 8 1 )
● Stow the luggage cover. ( →P. 8 2 )
● 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
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514
5-2. Steps to take in an emergency
10_IS250C/350C_U
If the retractable hardtop does not close
Unlock the trunk. (→P. 4 7 )
Open the trunk fully.
If the retractable hardtop does not clos e when the switch is pressed, check
that all operating conditions are met. ( →P. 8 6 )
If the retractable hardtop will not close even though all operating condi-
tions have been met, there may be a malfunction. Immediately have the
vehicle inspected by your Lexus dealer.
As a temporary measure, the following procedure can be performed to
manually close the retractable hardtop.
■ Notes for manually closin g the retractable hardtop
● This procedure requires 2 people.
● There is some risk of damage to the vehicle during the procedure,
such as when applying considerable force or removing and
installing various parts. If you are unsure of how to perform this
procedure properly, it is recommended that you contact your
Lexus dealer.
● Protect your hands with gloves etc. when placing them in narrow
spaces.
● Before starting the procedure, turn the “ENGINE START STOP”
switch off.
STEP1
STEP2