Page 479 of 578
478
5-2. Steps to take in an emergency
IS F_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.
(Flashing)
(If equipped)
Indicates that the moon
roof is not fully closed
(with the “ENGINE
START STOP” switch
OFF and the driver’s
door opened).
Close the moon roof.
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.
(Flashing)
Indicates that the auto-
matic transmission fluid
temperature is too high
→ P. 1 4 6
Wa r n i n g m e s s a g eDetailsCorrection procedure
Page 484 of 578
5
When trouble arises
483
5-2. Steps to take in an emergency
IS F_U
Follow the correction procedures.After taking the specified steps to co rrect the suspected problem, check
that the warning light turns off.
Interior
buzzerExterior buzzerWa r n i n g m e s s a g eDetailsCorrection
procedure
Once
(Comes on for 10 sec- onds.)
Indicates that an
attempt was
made to start the
engine without
the electronic
key being
present, or the
electronic key
was not function-
ing normally.
Start the engine
with the elec-
tronic key
present.
*
Once3 times
(Flashing)
Indicates that a
door other than
the driver’s door
has been opened
and closed with
the “ENGINE
START STOP”
switch in any
mode other than
OFF and the
electronic key
has been taken
out of the detec-
tion area.
Confirm the loca-
tion of the elec-
tronic key.
Page 485 of 578
484
5-2. Steps to take in an emergency
IS F_U
Once3 times
Indicates that the
driver’s door has
been opened and
closed with the
shift lever in P, the
“ENGINE START
STOP” switch in
any mode other
than OFF and the
electronic key
has been taken
out of the detec-
tion area.
Tu r n t h e
“ENGINE START
STOP” switch
OFF or confirm
the location of the
electronic key.
Con-
tinuousCon-
tinuous
(Displayed alternately)(Flashing)
Indicates that the
driver’s door has
been opened and
closed with the
shift lever out of
in P, the
“ENGINE START
STOP” switch in
any mode other
than OFF and the
electronic key
has been taken
out of the detec-
tion area.
• Shift the shift lever to P.
•Confirm the
location of the
electronic key.
InteriorbuzzerExterior buzzerWarning messageDetailsCorrection
procedure
Page 486 of 578
5
When trouble arises
485
5-2. Steps to take in an emergency
IS F_U
Once(Comes on for 10 sec-onds.)
(Flashing)
Indicates that the
key battery is low.Replace the bat-
tery. ( →P. 4 2 9 )
Indicates that the
“ENGINE START
STOP” switch has
been turned
twice to ACCES-
SORY mode
without starting
the engine when
a closed door is
opened.
Press the
“ENGINE START
STOP” switch
while applying the
brakes.
(Flashing)
Indicates that the
steering lock has
not released
within 3 seconds
of pressing the
“ENGINE START
STOP” switch.Press the
“ENGINE START
STOP” switch
again while turn-
ing the steering
wheel with the
brake pedal
depressed.
Interior
buzzerExterior buzzerWa r n i n g m e s s a g eDetailsCorrection
procedure
Page 498 of 578
5
When trouble arises
497
5-2. Steps to take in an emergency
IS F_U
If the shift lever cannot be shifted from P
If the shift lever cannot be shifted with your foot on the brake, there may be
a problem with the shift lock system (a system to prevent accidental opera-
tion of the shift lever). Have the vehicle inspected by your Lexus dealer
immediately.
The following steps may be used as an emergency measure to ensure that
the shift lever can be shifted.
Set the parking brake.
Turn the “ENGINE START STOP” switch to IGNITION ON
mode.
Depress the brake pedal.
Pry the cover up with a flathead
screwdriver or equivalent.
Press the shift lock override but-
ton.
The shift lever can be shifted
while the button is pressed.
STEP1
STEP2
STEP3
STEP4
STEP5
Page 501 of 578
500
5-2. Steps to take in an emergency
IS F_UAfter the operation is completed,
reinstall the cover.
Hook the upper claw of the cover
onto the upper catch on the vehi-
cle side, and then push on the
lower side of the cover.
Make sure that the lower claw of
the cover is securely fastened to
the lower catch on the vehicle side.
If the cover is not securely
attached, it may fall off while driv-
ing.
Tr u n k
Turn the mechanical key clock-
wise to open.
Changing “ENGINE START STOP” switch modes and starting the engine
Shift the shift lever to P and apply the brakes.
STEP3
STEP1
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5
When trouble arises
501
5-2. Steps to take in an emergency
IS F_UTouch the Lexus emblem side of
the electronic key to the
“ENGINE START STOP” switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
the “ENGINE START STOP”
switch if any of the doors is opened
and closed while the key is touched
to the switch.
To change “ENGINE START STOP” switch modes: Within 10
seconds of the buzzer sounding, release the brake pedal and
press the “ENGINE START STOP” switch. Modes can be
changed each time the switch is pressed. (
→P. 1 3 4 )
To start the engine: Press the “ENGINE START STOP” switch
within 10 seconds after the buzzer sounds, keeping the brake
pedal depressed.
In the event that the engine still cannot be started, contact your Lexus
dealer.
STEP2
■Stopping the engine
Shift the shift lever to P and press the “ENGINE START STOP” switch as you nor-
mally do when stopping the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immediately when the battery depletes.
( → P. 429)
STEP3
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5
When trouble arises
503
5-2. Steps to take in an emergency
IS F_U
■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, etc.
■Charging the battery
The electricity stored in the battery will discharge gradually even when the vehi-
cle 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 dis-
charge, and the engine may be unable to start. (The battery recharges automat-
ically during driving.)
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 with the “ENGINE START
STOP” switch OFF.
Maintain the engine speed of the second vehicle and turn the
“ENGINE START STOP” switch to IGNITION ON mode,
then start the vehicle’s engine.
Once the vehicle’s engine has started, remove the jumper
cables in the exact reverse order in which they were con-
nected.
Once the engine starts, have the vehicle checked at your Lexus dealer
as soon as possible.STEP2
STEP3
STEP4
STEP5