Page 489 of 594
488
5-2. Steps to take in an emergency
IS350/250_U
Follow the correction procedures.After taking the specified steps to correct the suspected problem, check
that the warning light turns off.
InteriorbuzzerExterior buzzerWarning messageDetailsCorrection
procedure
Once
(Comes on for 10 seconds.)
(Flashing)
Indicates that an
attempt was made
to start the engine
without the elec-
tronic key being
present, or the
electronic key was
not functioning
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
or closed with the
“ENGINE START
STOP” switch in
any mode other
than OFF and the
electronic key
outside of the
detection area.
Confirm the loca-
tion of the elec-
tronic key.
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5
When trouble arises
497
5-2. Steps to take in an emergency
IS350/250_U
■When using the compact spare tire
As the compact spare tire is not equipped with the tire pressure warning valve and
transmitter, low inflation pressure of the spare tire will not be indicated. Also, if you
replace the compact spare tire after the tire pressure warning light comes on, the
light remains on.
■If you have a flat rear tire on a road covered with snow or ice
Install the compact spare tire on the front of the vehicle. Perform the following steps
and fit tire chains to the rear tires.Replace a front tire with the compact spare tire.
Replace the flat rear tire with the tire removed from the front of the vehi-
cle.
Fit tire chains to the rear tires.
■After completing the tire change
The tire pressure warning system must be reset. ( →P. 4 1 4 )
CAUTION
■Using the tire jack
Improper use of the tire jack may lead to death or serious injuries due to the vehicle
suddenly falling off the jack.
●Do not use the tire jack for any purpose other than replacing tires or installing and
removing tire chains.
●Only use the tire jack that comes with this vehicle for replacing a flat tire.
Do not use it on other vehicles, and do not use other tire jacks for replacing tires
on this vehicle.
●Always check that the tire jack is securely set to the jack point.
●Do not put any part of your body under the vehicle while it is supported by a jack.
●Do not start or run the engine while your vehicle is supported by the jack.
●Do not raise the vehicle while someone is in it.
●When raising the vehicle, do not put an object on or under the jack.
●Do not raise the vehicle to a height greater than that required to replace the tire.
STEP1
STEP2
STEP3
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5
When trouble arises
511
5-2. Steps to take in an emergency
IS350/250_U
■Avoiding a discharged battery
●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 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.)
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 the jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any part other than the intended terminal.
●Do not allow the jumper cables to come into contact with the “+” and “-” termi-
nals.
●Do not allow open flame or use matches, cigarette lighters or smoke near the
battery.
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.STEP5
STEP6
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5
When trouble arises
513
5-2. Steps to take in an emergency
IS350/250_U
If your vehicle overheats
If your engine overheats:
Stop the vehicle in a safe place and turn off the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: Stop the engine. Carefully lift the hood after the steam sub-
sides and then restart the engine.
If you do not see steam: Leave the engine running and carefully lift the hood.
Check to see if the cooling fans are operating.
If the fans are operating: Wait until the temperature of the engine (shown on the
instrument cluster) begins to fall and then stop the engine.
If the fans are not operating: Stop the engine immediately and call your local Lexus
dealer.
After the engine has cooled
down sufficiently, check the
engine coolant level and inspect
the radiator core (radiator) for
any leaks.
If the engine compartment
cover needs to be removed:
→P. 3 9 9
STEP1
STEP2
STEP3
STEP4
Page 515 of 594
514
5-2. Steps to take in an emergency
IS350/250_U
■Overheating
If you observe the following, your vehicle may be overheating.
●The engine coolant temperature gauge enters the red zone or a loss of power is
experienced.
●Steam is coming from under the hood.
CAUTION
■To prevent an accident or injury when inspecting under the hood of your vehicle
●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, causing serious
injury such as burns.
●Keep hands and clothing away from the fans and other belts while the engine is
running.
●Do not loosen the radiator cap while the engine and radiator are hot.
Serious injury, such as burns, may result from hot coolant and steam released
under pressure.
Add engine coolant if required.
Water can be used in an emer-
gency if engine coolant is
unavailable. (→P. 5 2 7 )
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP5
Page 525 of 594
524
6-1. Specifications
IS350/250_U
Lubrication system
*: 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.
IS250
■ Engine oil selection
“Toyota Genuine Motor Oil” is used in your Lexus vehicle. Use Lexus
approved “Toyota Genuine Motor Oil” or equivalent to satisfy the follow-
ing grade and viscosity.
Oil grade: ILSAC multigrade engine oil
Recommended viscosity: SAE 0W-20
SAE 0W-20 is the best choice for
good fuel economy and good
starting in cold weather.
If SAE 0W-20 is not available,
SAE 5W-20 oil may be used.
However, it must be replaced with
SAE 0W-20 at the next oil
change.
Oil capacity
(Drain and refill
reference*)
without filter
2WD models
AWD models
6.2 qt. (5.9 L, 5.2 Imp. qt.)
6.3 qt. (6.0 L, 5.3 Imp. qt.)
with filter
2WD models
AWD models
6.6 qt. (6.3 L, 5.5 Imp. qt.)
6.7 qt. (6.4 L, 5.6 Imp. qt.)
Outside temperature
Page 529 of 594
528
6-1. Specifications
IS350/250_U
Electrical system
Differential
Front
Rear
*: Your Lexus vehicle is filled with “Toyota Genuine Differential Gear Oil” at the factory. Use Lexus approved “Toyota Genuine Differential Gear Oil” or an
equivalent of matching quality to satisfy the above specification. Please contact
your Lexus dealer for further details.
Battery
Open voltage* at
68 °F (20 °C):12.6 12.8 V Fully charged
12.2
12.4 V Half charged
11.8
12.0 V Discharged
(*: Voltage checked 20 minutes after
the engine and all the lights are turned
off)
Charging rates5 A max.
Oil capacity0.74 qt. (0.70 L, 0.61 Imp. qt.)
Oil typeHypoid gear oil API GL-5
Oil viscosityAbove 0 °F (-18 °C): SAE90
Below 0 °F (-18 °C): SAE80W or SAE80W-90
Oil capacity
IS350:
1.42 qt. (1.35 L, 1.19 Imp. qt.)
IS250:
1.20 qt. (1.15 L, 1.01 Imp. qt.)
Oil type and viscosity*Toyota Genuine Differential Gear Oil LT 75W-85
GL-5 or equivalent
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581
Alphabetical index
IS350/250_U
If you have a flat tire ........................ 492
If you lose your keys ........................504
If you think something is wrong................................................... 469
If your vehicle becomes stuck ......516
If your vehicle has to be stopped in an emergency.............................. 518
If your vehicle needs to be
towed ................................................... 463
If your vehicle overheats..................513
Emergency flashers Switch ...................................................... 462
Engine Compartment ..................................... 397
Engine switch .......................................... 141
Hood ....................................................... 394
How to start the engine...................... 141
Identification number......................... 521
If the engine will not start ................ 501
Ignition switch.......................................... 141
Overheating...........................................513
Engine compartment cover............. 399
Engine coolant Capacity..................................................527
Checking ............................................... 404
Preparing and checking
before winter .................................... 206 Engine coolant temperature
gauge....................................................... 158
Engine immobilizer system..................90
Engine oil Capacity .................................................524
Checking ................................................ 401
Preparing and checking before winter ................................... 206
EPS .............................................................. 196
Event data recorder .................................21
First-aid kit storage belt ..................... 357
Floor mat ..................................................356
Fluid Brake ....................................................... 406
Washer ...................................................... 411
Fog lights Switch.........................................................176
Wattage ................................................. 536
Footwell lights ........................................325
Front fog lights Switch.........................................................176
Wattage ................................................. 536
Front passenger occupant
classification system .......................... 109
Front passenger's seat belt
reminder light...................................... 473
F
*: For vehicles with a navigation system, refer to the “Navigation System Owner’s Manual”.