Page 617 of 676

6178-2. Steps to take in an emergency
8
When trouble arises
IS200t_EE(OM53D77E)
■Stopping the engine
Shift the shift lever to P and press the engine switch as you normally do when stopping
the engine.
■Replacing the key battery
As the above procedure is a temporary measur e, it is recommended that the electronic
key battery be replaced immediately when the battery is depleted. ( P. 527)
■Alarm (if equipped)
Using the mechanical key to lock the 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 engine switch modes
Release the brake pedal and press the engine switch in step above.
The engine does not start an d modes will be changed each time the switch is pressed.
( P. 205)
■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. 641)
●Check if battery-saving mode is set. If it is set, cancel the function. (P. 142)
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 operate the me chanical key. It is possible for children and
other passengers to get caught in the power window or moon roof.
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Page 618 of 676
6188-2. Steps to take in an emergency
IS200t_EE(OM53D77E)
If you have a set of jumper (or booster) cables and a second vehicle with a 12-volt
battery, you can jump start your vehicle 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. 83)
Open the hood. ( P. 497)
If the vehicle battery is discharged
The following procedures may be used to start the engine if the vehicle’s bat-
tery is discharged.
You can also call any authorized Lexus retailer or Lexus authorized repairer,
or any reliable repairer.
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Page 619 of 676

6198-2. Steps to take in an emergency
8
When trouble arises
IS200t_EE(OM53D77E)
Connect the jumper cables according to the following procedure:
Left-hand drive vehicles
Right-hand drive vehicles 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.
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Page 620 of 676

6208-2. Steps to take in an emergency
IS200t_EE(OM53D77E)
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 any authorized Lexus
retailer or Lexus authorized repairer, or an y reliable repairer as soon as possible.
■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 stopped. (Vehicles with
a Stop & Start system: except when the engine is stopped by the Stop & Start system.)
●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
●In some cases, it may not be possible to unlock the doors using the smart entry & start
system when the battery is discharged. Us e the wireless remote control or the mechan-
ical 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.
●Vehicles with Stop & Start system:
For a while after the battery terminals have been disconnected or reconnected, for a
while after the battery has been replaced, the Stop & Start system may not automati-
cally stop the engine for approximately 5 to 60 minutes.
■When exchanging the battery (vehicles with Stop & Start system)
Use a battery specified for use with the Stop & Start system and equivalent to a genuine
battery. If an unsupported battery is used, Stop & Start system functions may be
restricted to protect the battery.
Also, battery performance may decrease and the engine may not be able to restart.
Contact any authorized Lexus retailers or Le xus authorized repairers, or any reliable
repairers.
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Page 621 of 676

6218-2. Steps to take in an emergency
8
When trouble arises
IS200t_EE(OM53D77E)
WARNING
■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.
Page 622 of 676

6228-2. Steps to take in an emergency
IS200t_EE(OM53D77E)
●The needle of the engine coolant temperature gauge (P. 93) enters the red
zone or a loss of engine power is experienced. (For example, the vehicle
speed does not increase.)
●“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” is
shown on the multi-information display.
●Steam comes out from under the hood.
Stop the vehicle in a safe place and turn off the air conditioning system, and
then stop the engine.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the engine has cooled down
sufficiently, inspect the hoses and
radiator core (radiator) for any
leaks.
Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact any authorized
Lexus retailer or Lexus authorized
repairer, or any reliable repairer.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
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Page 623 of 676
6238-2. Steps to take in an emergency
8
When trouble arises
IS200t_EE(OM53D77E)
Engine coolant reservoir:
The coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir.Reservoir cap
“FULL” line
“LOW” line
Intercooler coolant reservoir:
The coolant level is satisfactory if it is between the “F” and “L” lines on the res-
ervoir. Reservoir cap
“F” line
“L” line
Add coolant if necessary.
Water can be used in an emergency if coolant is unavailable.
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EngineIntercooler
Page 624 of 676

6248-2. Steps to take in an emergency
IS200t_EE(OM53D77E)
Start the engine and turn the air conditioning system on to check that the radi-
ator cooling fans operate and to check for coolant leaks from the radiator or
hoses.
The fans operate when the air conditioning system is turned on immediately after a
cold start. Confirm that the fans are operating by checking the fan sound and air flow.
If it is difficult to check these, turn the air conditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately and contact any authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer.
If the fans are operating:
Have the vehicle inspected at the nearest authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
Check if “Engine Coolant Temp High Stop in a Safe Place See Owner’s Man-
ual” is shown on the multi-information display.
If the message does not disappear:
Stop the engine and contact any author ized Lexus retailer or Lexus autho-
rized repairer, or any reliable repairer.
If the message is not displayed:
Have the vehicle inspected at the nearest authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
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