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 501 of 584

5018-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
■Stopping the engine
Shift the shift lever to P and press the engine switch as you normally do when stopping
the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediatel y when the battery is depleted. (P. 4 3 9 )
■Changing engine switch modes
Release the brake pedal and press the engine switch in step above.
The engine does not start and modes will be changed each time the switch is pressed.
( P. 1 6 0 )
■When the electronic key does not work properly
●Make sure that the smart access system wi th push-button start has not been deacti-
vated in the custom ization setting. If it is off, turn the function on.
(Customizable features P. 5 3 7 )
●Check if battery-saving mo de is set. If it is set, cancel the function. ( P. 115)
CAUTION
■When using the mechanical key and operating the power windows and moon roof
Operate the power window or moon roof afte r checking to make sure that there is no
possibility of any passenger having any of their body parts caught in the window or
moon roof.
Also, do not allow children to operate the mech anical key. It is possible for children and
other passengers to get caught in power window and moon roof.
3
Page 507 of 584
5078-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
The coolant level is satisfactory if it is
between the “FULL” and “LOW”
lines on the reservoir.Reservoir
“FULL”
“LOW”
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
Start the engine and turn the air conditioning system on to check that the radi-
ator cooling fans operate and to check for coolant leaks from the radiator or
hoses.
The fans operate when the air conditioning system is turned on immediately after a
cold start. Confirm that the fans are oper ating by checking the fan sound and air flow.
If it is difficult to check th ese, turn the air conditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
4
1
2
3
5
6
7
Page 514 of 584
5149-1. Specifications
IS350/250_U (OM53C50U)
■Oil capacity (Drain and refill [Reference*])
*: The engine oil capacity is a reference quantity to be used when changing the engine oil. Warm up and turn off the engine, wait more than 5 minutes, and check the oil level
on the dipstick.
Engine
IS250IS350
Model2.5 L 6-cylinder (4GR-FSE)
engine3.5 L 6-cylinder (2GR-FSE)
engine
Ty p e6-cylinder V type, 4-cycle, gasoline
Bore and stroke3.27 3.03 in.
(83.0 77.0 mm)3.70 3.27 in.
(94.0 83.0 mm)
Displacement152.5 cu. in. (2500 cm3)210.9 cu. in. (3456 cm3)
Valve clearance
(engine cold)Automatic adjustment
Drive belt tensionAutomatic adjustment
Fuel
Fuel typeUnleaded gasoline only
Octane Rating91 (Research Octane Number 96) or higher
Fuel tank capacity
(Reference)17.5 gal. (66.3 L, 14.6 Imp. gal.)
Lubrication system
2WDAW D
With filter6.6 qt. (6.2 L, 5.5 Imp. qt.)6.8 qt. (6.4 L, 5.6 Imp. qt.)
Without filter6.2 qt. (5.9 L, 5.2 Imp. qt.)6.3 qt. (6.0 L, 5.3 Imp. qt.)
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 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
Page 570 of 584

570Alphabetical index
IS350/250_U (OM53C50U)
Emergency flashers ............................. 456
Engine .........................................................514ACCESSORY mode....................... 160
Compartment....................................... 413
Engine switch ........................................ 159
Hood ........................................................... 411
How to start the engine ................... 159
Identification number ........................ 513
If the engine will not start............... 496
Ignition switch (engine switch)..... 159
Overheating ........................................ 506
Engine coolant......................................... 417 Capacity .................................................. 516
Checking..................................................417
Preparing and checking before winter ................................... 260
Engine coolant temperature gauge ..........................................................81
Engine immobilizer system ................. 69
Engine oil ...................................................414 Capacity .................................................. 514
Checking................................................. 414
Preparing and checking before winter ................................... 260
Engine switch .......................................... 159
Enhanced VSC ..................................... 240
EPS (Electronic Power Steering) ..........241 Function ....................................................241
Warning light ....................................... 467
Event data recorder (EDR) ...................10 First-aid kit storage belt......................374
Flat tire ...................................................... 486
Floor mats....................................................26
Fluid
Automatic transmission .................... 517
Brake......................................................... 518
Washer ................................................... 422
Fog lights..................................................... 181 Replacing light bulbs ....................... 452
Switch ......................................................... 181
Wattage ................................................... 521
Footwell light .......................................... 368 Wattage ................................................... 521
Front passenger occupant classification system ............................ 47
Front personal lights ........................... 369 Wattage ................................................... 521
Front seats ................................................. 120 Adjustment..............................................120
Cleaning................................................. 399
Correct driving posture .................... 28
Driving position memory................. 123
Head restraints .....................................128
Power easy access system ............. 123
Seat heaters .......................................... 367
Seat position memory ....................... 123
Seat ventilators.................................... 367F