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1-1. Hybrid system
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■Charging the hybrid battery (traction battery)
As the gasoline engine charges the hybrid battery (traction battery), the battery
does not need to be charged from an outside source. However, if the vehicle is left
parked for a long time the hybrid battery will slowly discharge. For this reason, be
sure to drive the vehicle at least once every few months for at least 30 minutes or
10 miles (16 km). If the hybrid battery becomes fully discharged and you are unable
to jump-start the vehicle with the 12-volt battery, contact your Lexus dealer.
■Charging the 12-volt battery
→P. 5 4 9
■After the 12-volt battery has discharg ed or has been changed or removed
The gasoline engine may not stop even if the vehicle is running on the hybrid battery
(traction battery). If this continues for a few days, contact your Lexus dealer.
■Sounds and vibrations specific to a hybrid vehicle
There may be no engine sounds or vibration even though the vehicle is able to
move. For safety, apply the parking brake and make sure to shift the shift position to
P when parked.
The following sounds or vibrations may occur when the hybrid system is operating
and are not a malfunction:
●Motor sounds may be heard from the engine compartment.
●Sounds may be heard from the hybrid battery (traction battery) behind the rear
seats when the hybrid system starts or stops.
●Sounds from the hybrid system may be heard when the trunk lid is open.
●Sounds may be heard from the transaxle when the engine is started or stopped,
or while the engine is idling.
●Engine sounds may be heard when accelerating sharply.
●Sounds may be heard due to regenerative braking when the brake pedal is
depressed and accelerator is loosened.
●Other sounds, such as motors and mechanical noises, may be heard from the
brake system when the brake pedal is depressed.
●Vibration may be felt when the gasoline engine starts or stops.
●Cooling fan sounds may be heard from the air intake vent on the side of rear left
seatback.
When driving in Eco drive mode, the fan noise may be louder than when driving
normally.
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5-2. Steps to take in an emergency
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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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5-2. Steps to take in an emergency
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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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5-2. Steps to take in an emergency
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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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5-2. Steps to take in an emergency
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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.