Page 488 of 588

4888-2. Steps to take in an emergency
IS250_EE(OM53C51E)
Indicates that the engine switch is turned off or turned to
ACCESSORY mode and the driver’s door is opened
while the lights are turned on
A buzzer also sounds.
→Turn the lights off.
(If equipped)
Indicates that the moon roof is not fully closed (with the
engine switch off, and the driver’s door open)
A buzzer also sounds.
→Close the moon roof.
Indicates that the windows are not fully closed (with the
engine switch off, and the driver’s door open)
A buzzer also sounds.
→Close all the windows.
(If equipped)
Indicates that the windows and the moon roof are not
fully closed (with the engine switch off, and the driver’s
door open)
A buzzer also sounds.
→Close all the windows and the moon roof.
Indicates a malfunction in the brake override system
A buzzer also sounds.
→Have the vehicle inspected by any authorized Lexus
dealer or repairer, or another duly qualified and
equipped professional.
Indicates that engine oil level is low
A buzzer also sounds.
→Check the level of engine oil, and add if necessary.
Indicates a malfunction in:
• The automatic headlight leveling system; or
• The Automatic High Beam system (if equipped)
• The LED headlight system (if equipped)
A buzzer also sounds.
→Have the vehicle inspected by any authorized Lexus
dealer or repairer, or another duly qualified and
equipped professional.
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)
(Flashes)
(Flashes)
(Flashes)
Page 489 of 588

4898-2. Steps to take in an emergency
8
When trouble arises
IS250_EE(OM53C51E)
Indicates that the accelerator and brake pedal are being
depressed simultaneously
→Release the accelerator or brake pedal.
Indicates that the washer fluid level is low
→Add washer fluid.
Indicates that remaining fuel is approximately 10 L (2.6
gal., 2.2 Imp. gal.) or less
→Refuel the vehicle.
Indicates that the TRC (Traction Control) system has
been deactivated
→Tu r n t h e T R C o n . (→P. 2 6 7 )
(If equipped)
Indicates that the fuel injectors require maintenance
soon
→Have any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional
add injector cleaner to the fuel tank and reset the
message as necessary.
(If equipped)
Indicates that the fuel injectors require maintenance
→Have any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional
add injector cleaner to the fuel tank and reset the
message.
(If equipped)
Indicates that the Automatic High Beam switch is
pressed while the headlights are in low beam.
→Turn the high beam on and press the Automatic
High Beam switch again.
(If equipped)
Indicates that, since the VSC (Vehicle Stability Control)
system was turned off, the pre-crash brake system oper-
ation is stopped
→Tu r n t h e V S C o n . (→P. 2 6 7 )
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)
Page 521 of 588

5218-2. Steps to take in an emergency
8
When trouble arises
IS250_EE(OM53C51E)
One of the following may be the cause of the problem:
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●The engine may be flooded.
Try to restart the engine again following correct starting procedures.
(→P. 1 9 2 )
●There may be a malfunction in the engine immobilizer system.
(→P. 77)
One of the following may be the cause of the problem:
●The battery terminal connections may be loose or corroded.
●The battery may be discharged. (→P. 5 2 7 )
The engine starting system may be malfunctioning due to an electrical problem
such as electronic key battery depletion or a blown fuse. However, an interim
measure is available to start the engine. (→P. 522)
If the engine will not start
If the engine will not start even though correct starting procedures are being
followed (→P. 192), consider each of the following points:
The engine will not start even though the starter motor operates nor-
mally.
The starter motor turns over slowly, the interior lights and headlights
are dim, or the horn does not sound or sounds at a low volume.
The starter motor does not turn over
Page 522 of 588

5228-2. Steps to take in an emergency
IS250_EE(OM53C51E)
One of the following may be the cause of the problem:
●One or both of the battery terminals may be disconnected.
●The battery may be discharged. (→P. 5 2 7 )
●There may be a malfunction in the steering lock system.
Contact any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional if the problem cannot be repaired, or if repair procedures are
unknown.
When the engine does not start, the following steps can be used as an interim
measure to start the engine if the engine switch is functioning normally:
Set the parking brake.
Shift the shift lever to P.
Turn the engine switch to ACCESSORY mode.
Press and hold the engine switch for about 15 seconds while depressing the
brake pedal firmly.
Even if the engine can be started using the above steps, the system may be mal-
functioning. Have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
The starter motor does not turn over, the interior lights and headlights
do not turn on, or the horn does not sound.
Emergency start function
1
2
3
4
Page 529 of 588

5298-2. Steps to take in an emergency
8
When trouble arises
IS250_EE(OM53C51E)
Start the engine of the second vehicle. Increase the engine speed slightly and
maintain at that level for approximately 5 minutes to recharge the battery of
your vehicle.
Open and close any of the doors of your vehicle with the engine switch off.
Maintain the engine speed of the second vehicle and start the engine of your
vehicle by turning the engine switch to IGNITION ON mode.
Once the vehicle’s engine has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the engine starts, have the vehicle inspected at any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional as soon
as possible.
■Starting the engine when the battery is discharged
The engine cannot be started by push-starting.
■To prevent battery discharge
●Turn off the headlights and the audio system while the engine is off.
●Turn off any unnecessary electrical components when the vehicle is running at a low
speed for an extended period, such as in heavy traffic.
■Charging the battery
The electricity stored in the battery will discharge gradually even when the vehicle is not
in use, due to natural discharge and the draining effects of certain electrical appliances. If
the vehicle is left for a long time, the battery may discharge, and the engine may be
unable to start. (The battery recharges automatically during driving.)
■When recharging or replacing the battery
●For vehicles with an alarm: Make sure that the key is not inside the vehicle when
recharging or replacing the battery. The key may be locked in the vehicle if the alarm is
activated. (→P. 8 5 )
●In some cases, it may not be possible to unlock the doors using the smart entry & start
system when the battery is discharged. Use the wireless remote control or the mechan-
ical key to lock or unlock the doors.
●The engine may not start on the first attempt after the battery has recharged but will
start normally after the second attempt. This is not a malfunction.
●The engine switch mode is memorized by the vehicle. When the battery is recon-
nected, the system will return to the mode it was in before the battery was discharged.
Before disconnecting the battery, turn the engine switch off.
If you are unsure what mode the engine switch was in before the battery discharged, be
especially careful when reconnecting the battery.
4
5
6
7
Page 548 of 588
5489-1. Specifications
IS250_EE(OM53C51E)
Light bulbs*1
Light bulbsWTy p e
Exterior
Discharge headlights*235A
Front turn signal lights21B
Rear turn signal lights21B
Back-up lights16C
Outer foot lights5C
Interior
Door courtesy lights5C
Vanity lights8C
Interior light8C
Personal lights8C
Footwell lights3.8C
Trunk light5C
A: D4S discharge bulbs
B: Wedge base bulbs (amber)
C: Wedge base bulbs (clear)
*1: Light bulbs not listed in this table are LED bulbs.
*2: If equipped
Page 557 of 588

557
9 9-2. Customization
Vehicle specifications
IS250_EE(OM53C51E)
■Tu r n s i g n a l l e v e r (→P. 2 0 3 )
*1: After flashing the turn signal lights when turning left or right while this function is off
and the turn signal lever is moved to the first position in the direction of the flashing
light, the turn signal lights can be selected to be flashing or off.
*2: The turn signal lights keep flashing if the turn signal lever is moved to the first position
in the direction of flashing light.
*3: The turn signal lights will be off if the turn signal lever is moved to the first position in
the direction of flashing light.
■Automatic light control system (→P. 2 0 6 )
FunctionDefault settingCustomized setting
The number of times the turn sig-
nal lights flash automatically
when the turn signal lever is
moved to the first position during
a lane change
*1
3
5
——O7
Off*2
Off*3
123
FunctionDefault settingCustomized setting
Light sensor sensitivityStandard-2 to 2O—O
Time elapsed before headlights
automatically turn off30 seconds
60 seconds
——O90 seconds
120 seconds
Welcome light illumination con-
trolOnOff——O
123
Page 559 of 588
559
9 9-2. Customization
Vehicle specifications
IS250_EE(OM53C51E)
■Illumination (→P. 3 8 9 )
FunctionDefault settingCustomized setting
Time elapsed before the interior
lights turn off15 seconds
Off
O—O7. 5 s e c o n d s
30 seconds
Operation after the engine
switch is turned offOnOff——O
Operation when the doors are
unlockedOnOff——O
Operation when you approach
the vehicle with the electronic
key on your person
OnOff——O
Inside door handle lightsOnOff——O
Time elapsed before the outer
foot lights turn off15 seconds
Off
O—O7. 5 s e c o n d s
30 seconds
Operation of the outer foot lights
when you approach the vehicle
with the electronic key on your
person
OnOff——O
Operation of the outer foot lights
when the doors are unlocked
with the power door lock switchOnOff——O
123