Page 484 of 584

4848-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
Once
• When the doors were unlockedwith the mechanical key and then
the engine switch was pressed,
the electronic key could not be
detected in the vehicle.
• The electronic key could not be detected in the vehicle even after
the engine switch was pressed
two consecutive times.
Touch the electronic key to the
engine switch while depressing
the brake pedal.
Once
During an engine starting proce-
dure in the event that the electronic
key was not functioning properly
( P. 500), the engine switch was
touched with the electronic key.
Press the engine switch within
10 seconds of the buzzer sound-
ing.
Indicates that:
• With the engine switch off, the
doors were unlocked and then the
driver's door was opened and
closed
• The engine switch was turned to ACCESSORY mode without
starting the engine
• The shift lever was shifted to P or N from another shift position with
the engine switch in IGNITION
ON mode.
Press the engine switch while
depressing the brake pedal.
Once
The engine switch has been turned
off with the shift lever in a position
other than P or N.
Shift the shift lever to P.
Once
After the engine switch has been
turned off with the shift lever in a
position other than P, the shift lever
has been shifted to P.
Turn the engine switch off.
Interior
buzzerExteriorbuzzerWa r n i n g m e s s a g eDetails/Actions
(Flashes)
(Flashes)
(Flashes)
Page 485 of 584
4858-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
*: The engine may not be restarted depending on the vehicle condition.
■Wa r n i n g m e s s a g e s
P. 4 8 1
■Warning buzzer
P. 4 6 9
Power was turned off due to the
automatic power off function.
Next time when starting the
engine, increase the engine
speed slightly and maintain that
level for approximately 5 min-
utes to recharge the battery.
Con-
tinuous
Indicates that the engine was
stopped in an emer gency while driv-
ing
To restart the engine, shift the
shift lever to N and turn the
engine switch to IGNITION
ON mode.
*
Once
Indicates that the engine switch has
been pressed while driving
Except when emergency stop-
ping of the vehicle is needed,
immediately release the engine
switch.
Interior
buzzerExteriorbuzzerWa r n i n g m e s s a g eDetails/Actions
(Flashes)
(Flashes)
Page 500 of 584
5008-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Lexus emblem side of the
electronic key to the engine switch.
When the electronic key is detected, a
buzzer sounds and the engine switch
will turn to IGNITION ON mode.
When the smart access system with
push-button start is deactivated in cus-
tomization setting, the engine switch will
turn to ACCESSORY mode.
Firmly depress the brake pedal and check that is shown on the multi-
information display.
Press the engine switch.
In the event that the engine still cannot be started, contact your Lexus dealer.
Starting the engine
1
2
3
4
Page 503 of 584

5038-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
Connect the jumper cables according to the following procedure:Connect a positive jumper cable clamp to the positive (+) battery terminal
on your vehicle.
Connect the clamp on the other end of the positive cable to the positive (+)
battery terminal on the second vehicle.
Connect a negative cable clamp to the negative (-) battery terminal on the
second vehicle.
Connect the clamp at the other end of the negative cable to a solid, station-
ary, unpainted metallic point away from the battery and any moving parts,
as shown in the illustration.
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 your Lexus dealer as soon
as possible.3
1
2
3
4
4
5
6
7
Page 516 of 584
5169-1. Specifications
IS350/250_U (OM53C50U)
■Spark plug
Cooling system
IS250IS350
Capacity 11.1 qt. (10.5 L, 9.2 Imp. qt.) 9.8 qt. (9.3 L, 8.2 Imp. qt.)
Coolant type
Use either of the following:
• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-silicate,
non-amine, non-nitrite, and non-borate coolant with long-
life hybrid organic acid technology
Do not use plain water alone.
Ignition system
Make DENSO FK20HBR11
Gap0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.
Electrical system
Battery
Open voltage at 68F
(20 C):12.6 12.8 V Fully charged
12.2
12.4 V Half charged
11.8
12.0 V Discharged
(Check the voltage 20 minutes after the engine and all
lights are turned off.)
Charging rates5 A max.
Page 560 of 584

560
IS350/250_U (OM53C50U)What to do if... (Troubleshooting)
What to do if... (Troubleshooting)
●If you lose your mechanical keys, ne
w genuine mechanical keys can be made
by your Lexus dealer. ( P. 100)
●If you lose your electronic keys, the risk of vehicle theft increases significantly.
Contact your Lexus dealer immediately. ( P. 1 0 2 )
●Is the electronic key battery weak or depleted? ( P. 4 3 9 )
●Is the engine switch in IGNITION ON mode?
When locking the doors, turn the engine switch off. ( P. 1 6 0 )
●Is the electronic key left inside the vehicle?
When locking the doors, make sure that you have the electronic key on your
person.
●The function may not operate properly du e to the condition of the radio wave.
( P. 1 1 6 )
●Is the child-protector lock set?
The rear door cannot be opened from inside the vehicle when the lock is set.
Open the rear door from outside and then unlock the child-protector lock.
( P. 1 0 6 )
●The function to prevent the electronic ke y from being left inside the trunk will
operate and you can open the trunk as usual. Take the key out from the trunk.
( P. 111)
If you have a problem, check the following before contacting your Lexus
dealer.
The doors cannot be locked, unlocked, opened or closed
You lose your keys
The doors cannot be locked or unlocked
The rear door cannot be opened
The trunk lid is closed with the electronic key left inside
Page 561 of 584

561What to do if... (Troubleshooting)
IS350/250_U (OM53C50U)
●Did you press the engine switch while firmly depressing the brake pedal?
(P. 1 5 9 )
●Is the shift lever in P? ( P. 161)
●Is the electronic key anywhere detectable inside the vehicle? ( P. 1 1 4 )
●Is the steering wheel unlocked? ( P. 161)
●Is the electronic key battery weak or depleted?
In this case, the engine can be started in a temporary way. (P. 500)
●Is the battery discharged? ( P. 5 0 2 )
●Is the engine switch in IGNITION ON mode?
If you cannot release the shift lever by depressing the brake pedal with the
engine switch in IGNITION ON mode. ( P. 4 9 8 )
●It is locked automatically to prevent theft of the vehicle. ( P. 1 6 1 )
●Is the window lock switch pressed?
The power window except for the one at the driver’s seat cannot be operated
if the window lock switch is pressed. ( P. 1 3 8 )
●The auto power off function will be oper ated if the vehicle is left in ACCES-
SORY or IGNITION ON mode (the engine is not running) for a period of
time. ( P. 161)
If you think something is wrong
The engine does not start
The shift lever cannot be shifted from P even if you depress the brake
pedal
The steering wheel cannot be turned after the engine is stopped
The windows do not open or close by operating the power window
switches
The engine switch is turned off automatically
Page 562 of 584
562What to do if... (Troubleshooting)
IS350/250_U (OM53C50U)
●The seat belt reminder light is flashing
Are the driver and the front passenger wearing the seat belts? ( P. 4 6 7 )
●The parking brake indicator is on
Is the parking brake released? ( P. 1 7 2 )
Depending on the situation, other type s of warning buzzer may also sound.
( P. 466, 472)
●Did anyone inside the vehicle open a door during setting the alarm?
The sensor detects it and the alarm sounds. ( P. 7 1 )
To stop the alarm, turn the engine switch to IGNITION ON mode or start the
engine.
●Is the electronic key left inside the vehicle or the moon roof opened?
Check the message on the multi-information display. ( P. 4 7 2 )
●When a warning light turns on or a warning message is displayed, refer to
P. 4 6 6 , 4 7 2 . A warning buzzer sounds during driving
An alarm is activated and the horn sounds
A warning buzzer sounds when leaving the vehicle
A warning light turns on or a warning message is displayed