Page 625 of 692

6258-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
■Run-flat tires (A “RFT” or “DSST” mark is molded on the sidewall)
Take your vehicle to the nearest
Lexus dealer or authorized tire
dealer as soon as possible if any tire
goes flat.
The vehicle can be driven for a maxi- mum of 300 km (186 miles) at a
speed below 60 km/h (37 mph)
after the tire pressure warning light comes on. ( P. 578)
■In some conditions (such as at high temperatures)
You cannot continue driving for up to 300 km (186 miles).
■For the detailed informat ion on run-flat tires
See the tire warranty booklet.
If you have a flat tire (vehicles with run-flat tires)
Your vehicle is not equipped with a sp are tire, but instead you can continue
driving the vehicle with run-flat tires even if any tire goes flat.In this case, slow
down and drive with extra caution.
NOTICE
■When replacing the tires
When removing or fitting the wheels, tires or the tire pressure warning valve and trans-
mitter, contact any authorized Lexus retailer or Lexus authorized repairer, or any reli- able repairer as the tire pressure warning valve and transmitter may be damaged if not
handled correctly.
■When driving over bumps
If a vehicle has a flat tire, the vehicle height will be lower than usual. Ensure that nothing
strikes the bottom of the vehicle.
■To avoid damage to the tire pressure warning valves and transmitters
When a tire is repaired with liquid sealants , the tire pressure warning valve and trans-
mitter may not operate properly. If a liqui d sealant is used, contact any authorized
Lexus retailer or Lexus authoriz ed repairer, or any reliable repairer or other qualified service shop as soon as possible. Make sure to replace the tire pressure warning valve
and transmitter when replacing the tire. ( P. 526)
Page 626 of 692

6268-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
One of the following may be the cause of the problem:
●The electronic key may not be functioning properly. (P. 629)
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●There may be a malfunction in the immobilizer system. ( P. 86)
●There may be a malfunction in the steering lock system.
●The hybrid system may be malfunctioning due to an electrical problem such
as electronic key battery depletion or a blown fuse. However, depending on
the type of malfunction, an interim meas ure is available to start the hybrid sys-
tem. ( P. 627)
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( P. 631)
●The 12-volt battery terminal connections may be loose or corroded.
( P. 522)
If the hybrid system will not start
Reasons for the hybrid system not starting vary depending on the situation.
Check the following and perfor m the appropriate procedure:
The hybrid system will not start even though the correct starting proce-
dure is being followed. ( P. 219)
The interior lights and headlights are dim, or the horn does not sound or
sounds at a low volume.
Page 627 of 692

6278-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. (P. 631)
●One or both of the 12-volt battery terminals may be disconnected.
( P. 522)
Contact any authorized Lexus retailer or Lexus authorized repairer, or any reliable
repairer if the problem canno t be repaired, or if repair procedures are unknown.
When the hybrid system does not start, the following steps can be used as an
interim measure to start the hybrid system if the power switch is functioning nor-
mally.
Do not use this starting procedur e except in cases of emergency.
Set the parking brake.
Shift the shift lever to P.
Turn the power switch to ACCESSORY mode.
Press and hold the power switch for ab out 15 seconds while depressing the
brake pedal firmly.
Even if the hybrid system can be starte d using the above steps, the system may
be malfunctioning. Have the vehicle insp ected by any authorized Lexus retailer
or Lexus authorized repairer , or any reliable repairer.
The interior lights and headlights do not turn on, or the horn does not
sound.
Emergency start function
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Page 628 of 692
6288-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
■Doors
Use the mechanical key ( P. 139)
in order to perform the following
operations:
Locks all the doors
Closes the windows and moon
roof (turn and hold)*
Unlocks all the doors
Opens the windows and moon roof (turn and hold)*
*: This setting must be customized at any authorized Lexus retailer or Lexus autho-
rized repairer, or an y reliable repairer.
■Trunk
Turn the mechanical key clockwise
to open.
If the electronic key does not operate properly
If communication between the electronic key and vehicle is interrupted ( P.
159) or the electronic key cannot be us ed because the battery is depleted, the
smart entry & start system and wireless remote control cannot be used. In
such cases, the doors and trunk can be opened and the hybrid system can be
started by following the procedure below.
Locking and unlocking the doors, unlocking the trunk and key linked
functions
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Page 629 of 692
6298-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Lexus emblem side of the
electronic key to the power switch.
When the electronic key is detected, a buzzer sounds and th e power switch will
turn to ON mode.
When the smart entry & start system is deactivated in custom ization setting, the
power switch will turn to ACCESSORY
mode.
Firmly depress the brake pedal and check that is shown on the multi-
information display.
Press the power switch.
In the event that the hybrid system still cannot be started, contact any authorized
Lexus retailer or Lexus authorized repairer, or any reliable repairer.
Starting the hybrid system
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Page 630 of 692

6308-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
■Stopping the hybrid system
Shift the shift lever to P and pr ess the power switch as you normally do when stopping the
hybrid system.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediately when the battery is depleted. (P. 549)
■Alarm (if equipped)
Using the mechanical key to lock th e doors will not set the alarm system.
If a door is unlocked using the mechanical key when the alarm system is set, the alarm may be triggered.
■Changing power switch modes
Release the brake pedal and press the power switch in step above. The hybrid system does not start and modes will be changed each time the switch is
pressed. ( P. 220)
■When the electronic key does not work properly
●Make sure that the smart entry & start system has not been deactivated in the
customization setting. If it is off, turn the function on.
(Customizable features: P. 657)
●Check if battery-saving mode is set. If it is set, cancel the function. (P. 158)
WARNING
■When using the mechanical key and operating the power windows or moon roof
Operate the power window or moon roof after 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 op erate the mechanical key. It is possible for children and other passengers to get caught in the power window or moon roof.
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Page 631 of 692
6318-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
If you have a set of jumper (or booster) cables and a second vehicle with a 12-volt
battery, you can jump start your ve hicle by following the steps below.
Confirm that the electronic key is
being carried.
When connecting the jumper (or booster) cables, depending on the situa-
tion, the alarm may activate and doors
locked. (P. 94)
Open the hood ( P. 513) and fuse
box cover.
Remove the clips.
Push the tabs on either side to
detach the lock and lift the lid off
while pulling the lock plate.
If the 12-volt battery is discharged
The following procedures may be used to start the hybrid system if the 12-volt
battery is discharged.
You can also call any authorized Lexus retailer or Lexus authorized repairer,
or any reliable repairer.
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2
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Page 632 of 692
6328-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
Open the exclusive jump starting
terminal cover.
Connect the jumper cables accordin g to the following procedure:
Connect a positive jumper cable clamp to the exclusive jump starting ter-
minal 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 exclusive jump starting terminal
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 approximatel y 5 minutes to recharge the 12-volt bat-
tery of your vehicle.
Open and close any of the doors of yo ur vehicle with the power switch off.
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