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5617-2. Steps to take in an emergency
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When trouble arises
■Stopping the hybrid system
Shift the shift lever to P and press the power switch as you normally do when stop-
ping the hybrid system.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immedi ately when the battery is depleted. (P. 4 6 0 )
■Changing power switch modes
Release the brake pedal and press the power switch in step above.
The hybrid system does not start and modes will be changed each time the switch is
pressed.( P. 1 9 4 )
■When the electronic key does not work properly
●Make sure that the smart access system with push-button start has not been deac-
tivated in the customization setting. If it is off, turn the function on.
(Customizable features: P. 599)
●Check if battery-saving mode is set. If it is set, cancel the function. ( P. 1 2 9 )
CAUTION
■When using the mechanical key and operating the power windows and moon
roof
Operate the power window or moon roof af ter 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 mechanical key. It is possible for children
and other passengers to get caught in power window and moon roof.
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7-2. Steps to take in an emergency
If the 12-volt battery is discharged
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 trunk lid and remove
the 12-volt battery cover.
In the event that the trunk opener can-
not be used, use the mechanical key to
open the trunk. ( P. 559)
Connect 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
Negative (-) battery terminal on your vehicle
The following procedures may be used to start the hybrid system if the
12-volt battery is discharged.
You can also call your Lexus dealer or a qualified repair shop.
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5637-2. Steps to take in an emergency
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7
When trouble arises
Start the engine of the second vehicle. Increase the engine speed
slightly and maintain at that le vel for approximately 5 minutes to
recharge the 12-volt battery of your vehicle.
Open and close any of th e doors of your vehicle with the power switch
off.
Maintain the engine speed of the se cond vehicle and start the hybrid
system of your vehicle by turning the power switch to ON mode.
Make sure the “READY” indicator co mes 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 wh ich they were connected.
Once the hybrid system starts, have the vehicle inspected at your Lexus
dealer as soon as possible.
■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 compon ents when the vehicle is running at a
low speed for an extended period, such as in heavy traffic.
■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 elec-
trical 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.)
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5647-2. Steps to take in an emergency
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■When recharging or replacing the 12-volt battery
●Make sure that the key is not inside the vehicle when recharging or replacing the
12-volt battery. The key may be locked in the vehicle if the alarm is activated.
( P. 8 4 )
●In some cases, it may not be possible to unlock the doors using the smart access
system with push-button start when the 12-volt battery is discharged. Use the wire-
less remote control or the mechanical key to lock or unlock the doors.
●The hybrid system may not start on the fir st attempt after the 12-volt battery has
recharged but will start normally after the second attempt. This is not a malfunction.
●The power switch mode is memorized by the vehicle. When the 12-volt battery is
reconnected, the system will return to the mode it was in before the 12-volt battery
was discharged. Before disconnecting the 12 -volt battery, turn the power switch off.
If you are unsure what mode the power switch was in before the 12-volt battery dis-
charged, be especially careful when reconnecting the 12-volt battery.
CAUTION
■Avoiding 12-volt battery fires or explosions
Observe the following precautions to prev ent accidentally igniting the flammable
gas that may be emitted from the 12-volt 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 12-
volt battery.
Page 565 of 652

5657-2. Steps to take in an emergency
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When trouble arises
CAUTION
■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 precau-
tions when handling the 12-volt battery:
●When working with the 12-volt battery, always wear safety glasses and take care
not to allow any 12-volt battery fluids (aci d) to come into contact with skin, cloth-
ing or the vehicle body.
●Do not lean over the 12-volt battery.
●In the event that 12-volt 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 th e 12-volt 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 yo ur 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 4 2
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7-2. Steps to take in an emergency
If your vehicle overheats
■If the needle of the engine coolant temperature gauge enters the red
zone
Stop the vehicle in a safe place an d turn off the air conditioning sys-
tem, and then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has cooled down sufficiently, inspect the
hoses and cooling system for leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact your
Lexus dealer.
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( P. 91) enters
the red zone or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
●“Hybrid System Overheat” ( P. 527) is shown on the multi-informa-
tion display.
●Steam comes out from under the hood.
Correction procedures
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5677-2. Steps to take in an emergency
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7
When trouble arises
The coolant level is satisfactory if it is between the “FULL” and
“LOW” lines on the reservoir.
Reservoir
“FULL”
“LOW”
Coolant inlet cap
Add coolant if necessary.
( P. 569)
Water can be used in an emer-
gency if engine coolant is unavail-
able.
Start the hybrid system and turn the air conditioning system on to
check that the radiator cooling fa ns 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 sys-
tem on and off repeatedly. (The fans may not operate in freezing tempera-
tures.)
If the fans are not operating:
Stop the hybrid system immediately and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
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Page 568 of 652
5687-2. Steps to take in an emergency
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■If “Hybrid System Overheat” is shown on the multi-information dis-
play
Stop the vehicle in a safe place.
Stop the hybrid system and carefully lift the hood.
After the hybrid system has cooled down, inspect the hoses and radi-
ator core (radiator) for any leaks.Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact your
Lexus dealer.
The coolant level is satisfactory if it is between the “FULL” and
“LOW” lines on the reservoir.
Reservoir
“FULL”
“LOW”
Add coolant if necessary.
Water can be used in an emer-
gency if power control unit coolant
is unavailable.
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