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5
When trouble arises
477
5-2. Steps to take in an emergency
IS350/250_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 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.
Page 487 of 578

486
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 0 2 )
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
Page 491 of 578
490
5-2. Steps to take in an emergency
IS350/250_U
Emergency start function
When the engine does not start, the following steps can be used as an
interim measure to start the engine if the “ENGINE START STOP” switch
is functioning normally.Vehicles with an automatic transmission Set the parking brake.
Put the shift lever in P.
Set the “ENGINE START STOP” switch to ACCESSORY mode.
Press and hold the “ENGINE START STOP” switch for about 15
seconds while depressing the brake pedal firmly.
Vehicles with a manual transmission Set the parking brake.
Put the shift lever in N.
Set the “ENGINE START STOP” switch to the ACCESSORY
mode.
Push and hold the “ENGINE ST ART STOP” switch for about 15
seconds while depressing the brake pedal and clutch pedal firmly.
Even if the engine can be started using the above steps, the system may
be malfunctioning. Have the vehicle checked by your Lexus dealer.
STEP1
STEP2
STEP3
STEP4
STEP1
STEP2
STEP3
STEP4
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5
When trouble arises
499
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.
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
501
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.
Remove the engine compartment cover. ( →P. 388)
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.STEP1
STEP2
STEP3
STEP4
STEP5
Page 503 of 578
502
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 1 5 )
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP6
Page 517 of 578
516
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
Page 568 of 578

567
Alphabetical index
IS350/250_U
Engine compartment cover............. 388
Engine coolantCapacity...................................................515
Checking ............................................... 392
Preparing and checking before winter ......................................195
Engine coolant temperature gauge ........................................................ 151
Engine immobilizer system ................. 85
Engine oil Capacity................................................... 512
Checking ............................................... 389
Preparing and checking before winter ......................................195
Engine oil maintenance data ............. 391
EPS...............................................................185
Event data recorder............................ 459
First-aid kit storage belt......................347
Floor mat.................................................. 346
Fluid Brake ....................................................... 394
Washer ................................................... 399
Fog lights
Switch ........................................................168
Wattage ................................................. 524
Footwell lights.......................................... 315
Front fog lights Switch ........................................................168
Wattage ................................................. 524 Front passenger occupant
classification system .......................... 104
Front passenger's seat belt reminder light...................................... 463
Front seats Adjustment .................................................51
Driving position memory ..................53
Front turn signal lights
Switch.........................................................147
Wattage ..................................................524
Fuel Capacity .................................................... 511
Fuel gauge................................................ 151
Fuel pump shut off system............ 458
Gas station information ..................576
Information ............................................525
Refueling.................................................... 82
Fuel door ..................................................... 82
Fuel filler door ........................................... 82
Fuel pump shut off system.................458
Fuses .......................................................... 423
Garage door opener ......................... 350
Gas station information...................... 576
Gauges ........................................................151
Glove box ................................................320
Glove box light ......................................320
F
G