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5-2. Steps to take in an emergency
IS250C/350C_U
Starting the engine
Shift the shift lever to P and apply the brakes.Touch the Lexus emblem side of
the electronic key to the
“ENGINE START STOP” switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
the “ENGINE START STOP”
switch if any of the doors is opened
and closed while the key is touched
to the switch.
Press the “ENGINE START STOP” switch within 10 seconds
after the buzzer sounds, keeping the brake pedal depressed.
In the event that the engine still cannot be started, contact your Lexus
dealer.
STEP1
STEP2
STEP3
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5-2. Steps to take in an emergency
IS250C/350C_U
■Stopping the engine
Shift the shift lever to P and press the “ENGINE START STOP” switch as you nor-
mally do when stopping the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immediately when the battery depletes. (→P. 4 4 9 )
■Changing “ENGINE START STOP” switch modes
Within 10 seconds of the buzzer sounding, release the brake pedal and press the
“ENGINE START STOP” switch.
The engine does not start and modes w ill be changed each time the switch is
pressed. ( →P. 1 4 8 )
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5-2. Steps to take in an emergency
IS250C/350C_U
If the vehicle battery is discharged
The following procedures may be used to start the engine if the vehicle’s
battery is discharged.
You can call your Lexus dealer, or qualified repair shop.
If you have a set of jumper (or booster) cables and a second vehicle
with a 12-volt battery, you can jump start your Lexus following the steps
below.
Remove the engine compartment covers. ( →P. 4 1 8 )
Connecting the jumper cables.
Positive (+) battery terminal on your vehicle
Positive (+) battery terminal on the second vehicle
Negative (-) battery terminal on the second vehicle
Connect the jumper cable to ground on your vehicle 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 with the “ENGINE START
STOP” switch OFF.
STEP1
STEP2
STEP3
STEP4
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5-2. Steps to take in an emergency
IS250C/350C_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 vehi-
cle 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 dis-
charge, and the engine may be unable to start. (The battery recharges automat-
ically during driving.)
■When the battery is removed or discharged
Make sure that the key is not inside the vehicle when recharging or replacing the
battery. The key may be locked in the vehicle if the alarm is activated. (→P. 1 0 1 )
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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5-2. Steps to take in an emergency
IS250C/350C_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 fan is operating.
If the fan is operating: Wait until the temperature of the engine (shown on the
instrument cluster) begins to fall and then stop the engine.
If the fan is 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. 4 1 8
STEP1
STEP2
STEP3
STEP4
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5-2. Steps to take in an emergency
IS250C/350C_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 fan 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 measure if engine coolant
is unavailable. (→P. 5 5 9 )
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP5
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5-2. Steps to take in an emergency
IS250C/350C_U
NOTICE
■When adding engine coolant
Wait until the engine has cooled down before adding engine coolant.
When adding coolant, do so slowly. Adding cool coolant to a hot engine too quickly
can cause damage to the engine.
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5-2. Steps to take in an emergency
IS250C/350C_U
If the vehicle becomes stuck
CAUTION
■When attempting to free a stuck vehicle
If you choose to rock the vehicle back and forth to free it, make sure the surround-
ing area is clear, to avoid striking other vehicles, objects or persons. The vehicle
may also lunge forward or lunge back suddenly as it becomes free. Use extreme
caution.
■When shifting the shift lever
Be careful not to shift the shift lever with the accelerator pedal depressed.
This may lead to unexpected rapid acceleration of the vehicle that may cause an
accident and result in death or serious injury.
NOTICE
■To avoid damaging the transmission and other components
●Avoid spinning the wheels and do not rev the engine.
●If the vehicle remains stuck after trying these procedures, the vehicle may require
towing to be freed.
Carry out the following procedures if the tires spin or the vehicle becomes
stuck in mud, dirt, or snow.
Stop the engine. Set the parking brake and shift the shift lever
in P.
Remove the mud, snow, or sand from around the stuck tire.
Place wood, stones or some other material to help provide
traction under the tires.
Restart the engine.
Shift the shift lever to the D or R position and carefully apply
the accelerator to free the vehicle.
Turn off TRAC and VSC if these functions are hampering your
attempts to free the vehicle. (→P. 2 1 6 )
STEP1
STEP2
STEP3
STEP4
STEP5