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5-2. Steps to take in an emergency
IS350/250_UInstall the spare tire and loosely
tighten each nut by hand to
approximately the same amount.
Tighten the wheel nuts until the
tapered portion comes into loose
contact with the disc wheel seat.
Lower the vehicle.
Firmly tighten each nut two or
three times in the order shown in
the illustration.
Tightening torque:
76 ft•lbf (103 N•m, 10.5 kgf•m)
Stow the flat tire, tire jack and all tools.
STEP2
Disc wheel
seat
Tapered portion
STEP3
STEP4
STEP5
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5-2. Steps to take in an emergency
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■The compact spare tire
●The compact spare tire is identified by the label “TEMPORARY USE ONLY”
on the tire sidewall.
Use the compact spare tire temporarily only in an emergency.
●Make sure to check the tire pressure of the compact spare tire. (→P. 5 2 8 )
■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 6 )
STEP1
STEP2
STEP3
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5-2. Steps to take in an emergency
IS350/250_U
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.
●Use a jack stand if it is necessary to get under the vehicle.
Take particular care when lowering the vehicle to ensure that no one working on or
near the vehicle may be injured.
■Replacing a flat tire
Observe the following precautions to reduce the risk of death or serious injury.
●Never use oil or grease on the wheel bolts or wheel nuts.
Oil and grease may cause the wheel nuts to be excessively tightened, leading to
bolt or disc wheel damage. In addition, the oil or grease can cause the wheel nuts
to loosen and the wheel may fall off, causing a serious accident. Remove any oil or
grease from the wheel bolts or wheel nuts.
●Have the wheel nuts tightened with a torque wrench to 76 ft•lbf (103 N•m, 10.5
kgf•m) as soon as possible after changing wheels.
Failure to follow these precautions could cause the nuts to loosen and the wheels
may fall off, which could lead to an accident causing death or serious injury.
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5-2. Steps to take in an emergency
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CAUTION
■When using the spare tire
●Remember that your compact spare tire is specifically designed for use with your
vehicle. Do not use your compact spare tire on another vehicle.
●Do not use two compact spare tires simultaneously.
●Replace the compact spare tire with a standard tire as soon as possible.
●Avoid sudden acceleration, deceleration and braking, as well as sharp cornering.
■Speed limit when using the spare tire
Do not drive at speeds in excess of 50 mph (80 km/h) when a compact spare tire is
installed on the vehicle.
The compact spare tire is not designed for driving at high speeds. Failing to observe
this precaution may lead to an accident causing death or serious injury.
■When the spare tire is attached
The vehicle speed may not be correctly detected, and the following systems may
not operate correctly:
●ABS & brake assist
●VSC
●TRAC
●EPS
●VDIM
●Navigation system (if equipped)
●Intuitive parking assist (if equipped)
●Dynamic radar cruise control (if equipped)
●Cruise control (if equipped)
●PCS (if equipped)
●AFS (if equipped)
Also, not only can the following system not be utilized fully, it may actually negatively
effect the drive-train components:
●AWD system (if equipped)
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5-2. Steps to take in an emergency
IS350/250_U
NOTICE
■Do not drive the vehicle with a flat tire.
Do not continue driving with a flat tire.
Driving even a short distance with a flat tire can damage the tire and the wheel
beyond repair.
■Be careful when driving over bumps with the compact spare tire installed on the
vehicle.
The vehicle becomes lower when driving with the compact spare tire compared to
when driving with standard tires. Be careful when driving over uneven road sur-
faces.
■Driving with tire chains and the compact spare tire
Do not fit tire chains to the compact spare tire.
Tire chains may damage the vehicle body and adversely affect driving performance.
■When replacing the tires
When removing or fitting the wheels, tires or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and trans-
mitter may be damaged if not handled correctly.
■To avoid damaging the tire pressure warning valves and transmitters
Do not use liquid sealants on flat tires.
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5-2. Steps to take in an emergency
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If the engine will not start
If the engine will not start even though correct starting procedures are
being followed (
→P. 134), consider each of the following points.
■The engine will not start even when the starter motor operates
normally.
One of the following may be the cause of the problem.
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
● The engine may be flooded.
Try to restart the engine once more following correct starting
procedures. ( →P. 1 3 4 )
● There may be a malfunction in the engine immobilizer system.
(→ P. 8 6 )
■ The starter motor turns over slowly, the interior lights and head-
lights are dim, or the horn does not sound or sounds at a low vol-
ume.
One of the following may be the cause of the problem.
● The battery may be discharged. ( →P. 509)
● The battery terminal connections may be loose or corroded.
■ The starter motor does not turn ov er, the interior lights and head-
lights do not turn on, or the horn does not sound.
One of the following may be the cause of the problem.
● One or both of the battery terminals may be disconnected.
● The battery may be discharged. ( →P. 509)
● There may be a malfunction in the steering lock system.
Contact your Lexus dealer if the problem cannot be repaired, or if
repair procedures are unknown.
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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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5-2. Steps to take in an emergency
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If the shift lever cannot be shifted from P∗
If the shift lever cannot be shifted with your foot on the brake, 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
immediately.
The following steps may be used as an emergency measure to ensure that
the shift lever can be shifted.
Set the parking brake.
Turn the “ENGINE START STOP” switch to ACCESSORY
mode.
Depress the brake pedal.
Pry the cover up with a flathead
screwdriver or equivalent.
Press the shift lock override but-
ton.
The shift lever can be shifted
while the button is pressed.
STEP1
STEP2
STEP3
STEP4
STEP5
∗: If equipped