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5-2. Steps to take in an emergency
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If the electronic key does not operate properly
Locking and unlocking the doors and key linked functions
Use the mechanical key ( →P. 2 8 )
in order to perform the following
operations (driver’s door only):
Locks all the doors
Closes the windows and moon
roof (turn and hold)
*
Unlocks the door
Tu r n i n g t h e k e y r e a r w a r d u n l o c k s
the driver’s door. Turning the key
once again unlocks the other
doors.
Opens the windows and moon
roof (turn and hold)
*
*
: This setting must be customized at your Lexus dealer.
If communication between the electronic key and vehicle is interrupted
(→ P. 41) or the electronic key cannot be used because the battery is
depleted, the smart access system with push-button start and wireless
remote control cannot be used. In such cases, the doors can be opened or
the engine can be started by following the procedure below.
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5-2. Steps to take in an emergency
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Starting the engine
Ensure that the shift lever is in P and depress the brake pedal.Touch the Lexus emblem side of
the electronic key to the
“ENGINE START STOP” switch.
If any of the doors is opened or
closed while the key is being
touched to the switch, an alarm will
sound to indicate that the start
function cannot detect the elec-
tronic key.
Press the “ENGINE START STOP” switch within 10 seconds of
the buzzer sounding, keeping the brake pedal depressed.
In the event that the “ENGINE START STOP” switch still cannot be oper-
ated, contact your Lexus dealer.
STEP1
STEP2
■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 is depleted.
( → P. 6 5 2 )
■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 8 5 )
STEP3
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5-2. Steps to take in an emergency
GX460_OM_OM60J63U_(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 by following the
steps below.
Open the hood. ( →P. 6 1 7 )
Connecting the jumper cables according to the following procedure: 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.
STEP1
STEP2
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5-2. Steps to take in an emergency
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■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 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 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.)
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 START STOP” switch off.
Maintain the engine speed of the second vehicle and start the
engine of your vehicle by turning the “ENGINE START STOP”
switch to IGNI TION ON mode.
Once your 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.STEP3
STEP4
STEP5
STEP6
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5-2. Steps to take in an emergency
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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 + 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 bat-
tery.
■Battery precautions
The battery contains poisonous and corrosive acidic electrolyte, while related parts
contain lead and lead compounds. Observe the following precautions when han-
dling 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 vehi-
cle body.
●Do not lean over the battery.
●If the 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
battery-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 belt.
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5-2. Steps to take in an emergency
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If your vehicle overheats
If the 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 engine coolant temperature gauge begins to
fall and then stop the engine.
If the fan is not operating: Stop the engine and call your local Lexus dealer.STEP1
STEP2
STEP3
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5-2. Steps to take in an emergency
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After the engine has cooled
down sufficiently, check the
coolant level and inspect the
radiator core (radiator) for any
leaks.
If the engine compartment
cover needs to be removed.
(→ P. 6 1 9 )
Add engine coolant if required.
Water can be used as an emer-
gency measure if engine coolant
is unavailable. (→ P. 763)
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP4
STEP5
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5-2. Steps to take in an emergency
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■Overheating
In the following situations, 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 engine drive belt 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.
NOTICE
■When adding engine coolant
Wait until the engine has cooled down before adding coolant.
When adding coolant, do so slowly. Adding cold coolant to a hot engine too quickly
can cause damage to the engine.
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