
4718-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
CAUTION
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold and
inflated to the inflation pressure recommended by the vehicle manufacturer on the
vehicle placard or tire inflation pressure label (tire and load information label). (If your
vehicle has tires of a different size than the size indicated on the vehicle placard or tire
inflation pressure label [tire and load in formation label], you should determine the
proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire pressure moni-
toring system (TPMS-tire pressure warning system) that illuminates a low tire pressure
telltale (tire pressure warning light) when on e or more of your tires is significantly
under-inflated. Accordingly, when the low ti re pressure telltale (tire pressure warning
light) illuminates, you should stop and check yo ur tires as soon as possible, and inflate
them to the proper pressure. Driving on a significantly under-inflated tire causes the
tire to overheat and can lead to tire failure. Under-inflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle’s handling and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a substitute for proper
tire maintenance, and it is the driver’s responsibility to maintain correct tire pressure,
even if under-inflation has not reached the level to trigger illumination of the TPMS low
tire pressure telltale (tire pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warning system) mal-
function indicator to indicate when the system is not operating properly. The TPMS
(tire pressure warning system) malfunction indicator is combined with the low tire pres-
sure telltale (tire pressure warning light). When the system detects a malfunction, the
telltale will flash for approximately one minu te and then remain continuously illumi-
nated. This sequence will continue upon su bsequent vehicle start-ups as long as the
malfunction exists. When the malfunction indicator is illuminated, the system may not
be able to detect or signal low tire pressure as intended.
TPMS (tire pressure warning system) malfun ctions may occur for a variety of reasons,
including the installation of replacement or alternate tires or wheels on the vehicle that
prevent the TPMS (tire pressure warning system) from functioning properly. Always
check the TPMS (tire pressure warning syst em) malfunction telltale after replacing one
or more tires or wheels on your vehicle to ensure that the replacement or alternate
tires and wheels allow the TPMS (tire pressure warning system) to continue to function
properly.
NOTICE
■To ensure the tire pressure warning system operates properly
Do not install tires with different specificatio ns or makers, as the tire pressure warning
system may not operate properly.

4898-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
Remove the luggage mat.
Take out the jack handle from the
reverse side of the luggage mat.
Remove the spacer.
Take out the jack.For tightening
For loosening
If the jack is too ti ghtly installed to be
removed by hand, insert a tool, such
as the screwdriver included with the
vehicle, into the hole of the jack (por-
tion “A”) and loosen the jack.
Taking out the jack and jack handle
1
2
3
1
2

4988-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
Set the parking brake.
Turn the engine switch to ACCESSORY mode.
Depress the brake pedal.
Pry the cover up with a flathead
screwdriver or equivalent tool.
To prevent damage to the cover, cover
the tip of the screwdriver with a rag.
Press the shift lock override button.
The shift lever can be shifted while the
button is pressed.
If the shift lever cannot be shifted from P
If the shift lever cannot be shifted with your foot on the brake pedal, 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 imme-
diately.
The following steps may be used as an emergency measure to ensure that the
shift lever can be shifted:
1
2
3
4
5

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

5048-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
■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
●Make sure that the key is not inside the vehicle when recharging or replacing the bat-
tery. The key may be locked in the vehicle if the alarm is activated. ( →P. 7 2 )
●In some cases, it may not be possible to unlock the doors using the smart access system
with push-button start when the battery is discharged. Use the wireless remote control
or the mechanical 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.

5058-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
CAUTION
■Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable gas
that may be emitted from the battery:
●Make sure each jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any other than the intended terminal.
●Do not allow the other end of the jumper cable connected to the “+” terminal to come
into contact with any other parts or metal surfaces in the area, such as brackets or
unpainted metal.
●Do not allow the + and - clamps of the jumper cables to come into contact with each
other.
●Do not smoke, use matches, cigarette lighters or allow open flame near the battery.
■Battery precautions
The battery contains poisonous and corrosive acidic electrolyte, while related parts
contain lead and lead compounds. Observe the following precautions when handling
the battery:
●When working with the battery, always wear safety glasses and take care not to allow
any battery fluids (acid) to come into contact with skin, clothing or the vehicle body.
●Do not lean over the battery.
●In the event that battery fluid comes into contact with the skin or eyes, immediately
wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention can be
received.
●Always wash your hands after handling the battery support, terminals, and other bat-
tery-related parts.
●Do not allow children near the battery.
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in the
cooling fans or engine drive belt.

5088-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
CAUTION
■When inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
●If steam is seen coming from under the hood, do not open the hood until the steam
has subsided. The engine compartment may be very hot.
●Keep hands and clothing (especially a tie, a scarf or a muffler) away from the fans and
belts. Failure to do so may cause the hands or clothing to be caught, resulting in seri-
ous injury.
NOTICE
■When adding engine coolant
Add coolant slowly after the engine has cooled down sufficiently. Adding cool coolant
to a hot engine too quickly can cause damage to the engine.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust etc.).
●Do not use any coolant additive.
●While the engine and radiator are hot, do not
loosen or remove the coolant reservoir cap
or radiator cap. (The radiator cap is located
under the engine cover.)
High temperature steam or coolant could
spray out.

5229-1. Specifications
IS350/250_U (OM53C50U)
■Fuel tank opening for unleaded gasoline
To help prevent incorrect fueling, your vehicle has a fuel tank opening that only accom-
modates the special nozzle on unleaded fuel pumps.
■Gasoline quality
In very few cases, driveability problems may be caused by the brand of gasoline you are
using. If driveability problems persist, try chan ging the brand of gasoline. If this does not
correct the problem, consult your Lexus dealer.
■Gasoline quality standards
●Automotive manufacturers in the U.S.A., Europe and Japan have developed a specifi-
cation for fuel quality called the World-Wide Fuel Charter (WWFC), which is expected
to be applied worldwide.
●The WWFC consists of four categories that are based on required emission levels. In
the U.S., category 4 has been adopted.
●The WWFC improves air quality by lowering emissions in vehicle fleets, and improves
customer satisfaction through better performance.
Fuel information
You must only use unleaded gasoline in your vehicle.
XIS250
Select premium unleaded gasoline with an octane rating of 91 (Research
Octane Number 96) or higher required for optimum engine performance. If
91 octane cannot be obtained, you may use unleaded gasoline with an octane
rating as low as 87 (Research Octane Number 91). Use of unleaded gasoline
with an octane rating lower than 91 may result in engine knocking. Persistent
knocking can lead to engine damage and should be corrected by refueling
with higher octane unleaded gasoline.
XIS350
Select premium unleaded gasoline with an octane rating of 91 (Research
Octane Number 96) or higher required for optimum engine performance. If
91 octane cannot be obtained, you may use unleaded gasoline with an octane
rating as low as 87 (Research Octane Number 91). Use of unleaded gasoline
with an octane rating lower than 91 may result in engine knocking and signifi-
cantly reduced performance. Persistent knocking can lead to engine damage
and should be corrected by refueling with higher octane unleaded gasoline.
At minimum, the gasoline you use should meet the specifications of ASTM
D4814 in the U.S.A..