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485
5-2. Steps to take in an emergency
If you lose your keys
New genuine Lexus keys can be made by your Lexus dealer using one of
the other keys and the key number stamped on your key number plate.
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5-2. Steps to take in an emergency
If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk and key linked functions
Doors
Using the mechanical key in order
to per
form the following opera -
tions:
Locks all doors
Closes the windows/moon roof
(turn and hold)
Unlocks the door
Turning the key rearward unlocks
the driver's door. Turning the key
once again unlocks the other
doors.
Opens the windows/moon roof
(turn and hold)
Tr u n k
Turn the mechanical key clock-
wise to open.
If communication between the electron ic key and vehicle is interrupted
(
P. 7 ) or the electronic key cannot be used because the battery is
depleted, the smart access system with push-button start and wireless
r
emote control cannot be used. In such cases, the doors and trunk 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
Changing engine switch modes and starting the engine
Put the shift lever in “P” and apply the brakes.Touch the Lexus emblem side of
the electr
onic key to the engine
switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
engine switch if any of the doors is
opened and closed while the key is
touched to the switch.
To change engine switch modes: Within 5 seconds of the buzzer
sounding, release the brake peda l and pr
ess the engine switch.
Modes can be changed each time the switch is pressed. (
P. 9 7 )
To start the engine: Press the engi ne switch within 5 seconds af
ter
the buzzer sounds, keep the brake pedal depressed.
In the event that the engine still cannot be operated, contact your Lexus
dealer
.
STEP1
STEP2
■Stopping the engine
Shift the shift lever to P and press the engine switch as you normally do when stop-
ping the engine
■Replacing the key battery
As the above procedure is the temporary measure, it is recommended that the
el
ectronic key battery be replaced immediately when the battery depletes. ( P.
411 )
STEP3
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5-2. Steps to take in an emergency
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, Roadside Assistance or Lexus Customer
Se
rvice Assistance.
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.
GS350 only: Remove the engine compartment covers.
( P. 3 7 8 )
Connecting the jumper cables.
If required, remove all vent pl ugs from the booster battery. Lay a
cloth over the open vents on the booster batter
y. (This helps reduce
the explosion hazard, personal injuries and burns.)
Positive (+) battery terminal on your vehicle.
Positive (+) battery terminal on the second vehicle.
Negative (-) battery terminal on the second v
ehicle.
Negative (-) battery terminal or your vehicle.
STEP1
STEP2
GS430
GS350
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5-2. Steps to take in an emergency
■Avoiding a discharged battery
●Turn off the headlights and the audio system while the engine is turned off.
●Turn off any unnecessary electrical compon ents when the vehicle is running at a
low speed for an extended period, such as in heavy traffic, etc.
■When the battery is removed or discharged
The following systems must be initialized.
●Po w e r w i n d o w s (P. 4 3 )
●Variable gear ratio steering (P. 1 5 9 )
●Tire pressure warning system (P. 3 9 3 )
●Intuitive parking assist (P. 1 3 6)
Start the engine of the second vehicle. Increase the engine
speed slightly and maintain at that level for approximately five
minutes to recharge the battery of your vehicle.
Open and close any of the doors with the engine s
witch “OFF”.
Maintain the engine speed on th e second v
ehicle and turn the
engine switch to the “IG-ON” mode, then start the vehicle’s
engine.
Once the vehicle’s engine ha s star
ted, remove the jumper
cables in the exact reverse ord er in which they w
ere con-
nected.
Once the engine starts, have the ve hicle check
ed at your Lexus dealer
as soon as possible.
STEP3
STEP4
STEP5
STEP6
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5-2. Steps to take in an emergency
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 pa rt other than the intended terminal.
●Do not allow the jumper cables to come into contact with the “+” and “-” termi-
nals.
●Do not allow open flame or use matches, cigarette lighters or smoke 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 han-
dling the battery:
●When working with the battery, always we ar 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.
●In the event that battery fluid comes into contact with the skin or eyes, immedi-
ately 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.
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5-2. Steps to take in an emergency
NOTICE
■To prevent damaging the vehicle
Do not pull- or push-start the vehicle, because the three-way catalytic converter
may overheat and become a fire hazard.
■When handling jumper cables
Be careful that the jumper cables do not become tangled in the cooling fan or any
of the belts when connecting or disconnecting them.
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5-2. Steps to take in an emergency
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 and car efully lif
t the hood.
If you do not see steam: Leave the engine running and carefully lift the hood.
Remove the engine compartment cover. ( P. 3 7 8 )
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 immediately and call y
our local Lexus
dealer.
After the engine has cooled
do
wn sufficiently, check the
coolant level and inspect the
radiator core (radiator) for any
leaks.
STEP1
STEP2
STEP3
STEP4
STEP5