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If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk and key linked functions
DoorsUse the mechanical key (→P. 4 2 )
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
Turning the key rearward unlocks
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. 52) 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 and trunk can be
opened and the hybrid system can be started by following the procedure
below.
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Turn the mechanical key clock-
wise to open.
Changing “POWER” switch modes and starting the hybrid system
Depress the brake pedal. Touch the Lexus emblem side of
the electronic key to the
“POWER” 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.
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HS250h_U_75050UTo change “POWER” switch modes: Within 10 seconds of the
buzzer sounding, release the brake pedal and press the
“POWER” switch. Modes can be ch
anged each time the switch is
pressed. (→ P. 153)
To start the hybrid system: Press the “POWER” switch within 10
seconds of the buzzer sounding, keeping the brake pedal
depressed.
In the event that the hybrid system still cannot be operated, contact your
Lexus dealer.
■Stopping the hybrid system
Set the parking brake, shift the shift position to P and press the “POWER” switch as
you normally do when stopping the hybrid system. ( →P. 1 5 3 )
■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. 4 6 7 )
■When the electronic key does not work properly
Make sure that the smart access system with push-button start has not been deacti-
vated in the customization setting. If it is off, turn the function on.
(Customizable features →P. 5 8 4 )
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If the vehicle 12-volt battery is discharged
The following procedures may be used to start the hybrid system if the vehi-
cle’s 12-volt battery is discharged.
You can also call your Lexus dealer or a 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 vehicle by following the
steps below.
Open the hood and fuse box
cover.
Push the tab in and lift the lid off.
Open the exclusive jump start-
ing terminal cover.
Slightly pull the tab to open the
cover.
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Connect the jumper cables according to the following procedure:Connect a positive jumper cable clamp to the exclusive jump start-
ing terminal on your vehicle
Connect the clamp on the other end of the positive cable to the pos-
itive (+) 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,
stationary, 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 that level for approximately 5 min-
utes to recharge the 12-volt battery of your vehicle.
Maintain the engine speed of th e second vehicle and start the
hybrid system of your vehicle by turning the “POWER” switch
to ON mode.
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■Starting the hybrid system when the 12-volt battery is discharged
The hybrid system cannot be started by push-starting.
■To prevent 12-volt battery discharge
●Turn off the headlights and the audio system while the hybrid system 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.
■When the 12-volt battery is discharged
●The hybrid system may not start. (→P. 4 4 8 )
●If the 12-volt battery is depleted with the shift position in P, it will not be possible
to shift out of P. In this case, the vehicle cannot be towed without lifting both
front wheels because the front wheels are locked by the parking lock.
(→ P. 4 9 5 )
●When the 12-volt battery is reconnected, start the hybrid system, depress the
brake pedal, and confirm that it is possible to shift into each shift position.
■Charging the 12-volt battery
The electricity stored in the 12-volt 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 12-volt battery may dis-
charge, and the hybrid system may be unable to start. (The 12-volt battery
recharges automatically while the hybrid system is operating.)
Make sure the “READY” indicator comes on. If the indicator
does not come on, contact your Lexus dealer.
Once the hybrid system has started, remove the jumper cables
in the exact reverse order from which they were connected.
Close the exclusive jump starting terminal cover and reinstall
the fuse box cover.
Once the hybrid system starts, ha ve the vehicle inspected at your
Lexus dealer as soon as possible.
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CAUTION
■Avoiding battery fires or explosions
The flammable gas that may be generated by the assisting vehicle battery may
catch fire and explode. Make sure to observe the following to prevent fire or sparks.
●Make sure each 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 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 allow open flame or use matches, cigarette lighters or smoke near the
battery.
■12-volt battery precautions
The 12-volt battery contains poisonous and corrosive acidic electrolyte, while
related parts contain lead and lead compounds. Observe the following precautions
when handling the 12-volt battery:
●When working with the 12-volt 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 12-volt 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 12-volt battery.
■After recharging the 12-volt battery
Have the 12-volt battery inspected at your Lexus dealer as soon as possible.
If the 12-volt battery is deteriorating, continued use may cause the 12-volt battery to
emit a malodorous gas, which may be detrimental to the health of passengers.
■When replacing the 12-volt battery
→P. 4 5 0
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NOTICE
■Exclusive jump starting terminal precaution
The exclusive jump starting terminal is to be used when charging the 12-volt battery
from another vehicle in an emergency. It cannot be used to jump start another vehi-
cle.
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in
the cooling fans or belt.