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5828-2. Steps to take in an emergency
RC300h_EE(OM24740E)
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.
Confirm that the electronic key is
being carried.
When connecting the jumper (or booster) cables, depending on the situa-tion, the alarm may activate and doors
locked. (P. 104)
Open the hood ( P. 471) and fuse
box cover.
Remove the clips.
Push the tabs on either side to
detach the lock and lift the lid off
while pulling the lock plate.
If the 12-volt battery is discharged
The following procedures may be used to start the hybrid system if the 12-volt
battery is discharged.
You can also call any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional.
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5838-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
Open the exclusive jump starting
terminal cover.
Connect the jumper cables according to the following procedure:
Connect a positive jumper cable clamp to the exclusive jump starting ter-
minal on your vehicle.
Connect the clamp on the other end of the positive cable to the positive (+)
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, station-
ary, 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 at that level for approximately 5 minutes to recharge the 12-volt bat-
tery of your vehicle.
Open and close any of the doors of your vehicle with the power switch off.
Maintain the engine speed of the seco nd vehicle and start the hybrid system
of your vehicle by turning the power switch to ON mode.
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5848-2. Steps to take in an emergency
RC300h_EE(OM24740E)
Make sure the “READY” indicator comes on. If the indicator does not come
on, contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
Once the hybrid system has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the hybrid system starts, have the vehicle inspected at any authorized
Lexus dealer or repairer, or another duly qualified and equipped professional 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 components 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 electrical appli- ances. If the vehicle is left for a long time, the 12-volt battery may discharge, and thehybrid system may be unable to start. (The 12-volt battery recharges automatically while
the hybrid system is operating.)
■When recharging or replacing the 12-volt battery
●In some cases, it may not be possible to unlock the doors using the smart entry & start
system when the 12-volt battery is discharg ed. Use the wireless remote control or the mechanical key to lock or unlock the doors.
●The hybrid system may not start on the first 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 mod e it was in before the 12-volt battery was
discharged. Before disconnecting the 12-v olt 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.
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5858-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
WARNING
■Avoiding 12-volt battery fires or explosions
Observe the following precautions to preven t 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 notunintentionally 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 light ers or allow open flame near the 12-volt 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 han-
dling 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 (acid) to come into contact with skin, clothing 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, 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 bereceived.
●Always wash your hands after handling the 12-volt battery support, terminals, andother 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 any authorized Lexus dealer or repairer, or another duly qualified and equipped professional as soon as possible.
If the 12-volt battery is deteriorating, co ntinued use may cause the 12-volt battery to emit a malodorous gas, which may be de trimental to the health of passengers.
■When replacing the 12-volt battery
P. 483
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5868-2. Steps to take in an emergency
RC300h_EE(OM24740E)
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in the cooling fans or belt.
■Exclusive jump starting terminal
The exclusive jump starting terminal is intended to charge the 12-volt battery on your vehicle from another vehicle in an emergency. Do not use the exclusive jump starting
terminal to jump start another vehicle.