Battery Lexus GS300h 2017 Repair Manual

4927-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
■Warning message in radar cruise mode (if equipped)
In the following cases, the warn ing message may not be displayed even if vehicle-to-vehi-
cle distance decreases:
●When your vehicle and the vehicle ahead are traveling at the same speed or the vehicle
ahead is traveling more quickly than your vehicle
●When the vehicle ahead is traveling at a very low speed
●Immediately after cruise control speed is set
●At the instant the accelerator pedal is depressed
■Open door warning message
The open door warning message continues to display until a door or the trunk is fully
closed, even if the power switch is turned off. However, approximately 20 minutes after a
door or the trunk is not fully closed, the 12-volt battery-saving function operates and the
display turns off even though a door or the trunk is not fully closed.
■Warning buzzer
In some cases, the buzzer may not be heard because of noisy place or an audio sound.

4967-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)

Power was turned off due to the
automatic power off function. Next time when starting the
hybrid system, operate the
hybrid system for approximately
5 minutes to recharge the 12-
volt battery.
OnceThe electronic key has a low battery. Replace the electronic key bat-
tery. ( P. 435)
Once
The driver’s door was opened and
closed with the power switch turned
off and then the power switch was
put in ACCESSORY mode twice
without the hybrid system being
started. Press the power switch while
depressing the brake pedal.
During an hybrid system starting
procedure in the event that the elec-
tronic key was not functioning prop-
erly ( P. 528), the power switch
was touched with the electronic key.  Press the power switch within 10
seconds of the buzzer sounding.
Once
The steering lock could not be
released within 3 seconds of the
power switch being pressed. Press the power switch while
depressing the brake pedal and
moving the steering wheel left
and right.
Interior
buzzerExteriorbuzzerWarning messageDetails/Actions
(Flashes)

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7
7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
If the hybrid system will not start
One of the following may be the cause of the problem: ●The electronic key may not be functioning properly. ( P. 528)
● There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
● There may be a malfunction in the immobilizer system. ( P. 85)
● There may be a malfunction in the steering lock system.
● The hybrid system may be malfunctioning due to an electrical problem such
as electronic key battery depletion or a blown fuse. However, depending on
the type of malfunction, an interim measure is available to start the hybrid sys-
tem. ( P. 524)
One of the following may be the cause of the problem: ● The 12-volt battery may be discharged. ( P. 530)
● The 12-volt battery terminal connections may be loose or corroded. ( P. 412)
One of the following may be the cause of the problem: ● The 12-volt battery may be discharged. ( P. 530)
● One or both of the 12-volt battery terminals may be disconnected. ( P. 412)
Contact any authorized Lexus retailer or Le xus authorized repairer, or any reliable
repairer if the problem cannot be repaired , or if repair procedures are unknown.
Reasons for the hybrid system not starting vary depending on the situation.
Check the following and perform the appropriate procedure:
The hybrid system will not start even though the correct starting proce-
dure is being followed. ( P. 217)
The interior lights and headlights are dim, or the horn does not sound or
sounds at a low volume.
The interior lights and he adlights do not turn on, or the horn does not
sound.

525
7
7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
If the parking brake cannot be released
●Shift the shift lever to P.
● Turn the power switch off.
● Check that the parking brake indicator is off.
● Chock the tires.
Take out the parking brake release
tool and the screwdriver from the
trunk. ( P. 499, 511)
Fit the parking brake release tool into
the screwdriver handle.
Vehicles with spare tire: Take out the spare tire. ( P. 501)
Vehicles without spare tire: Remove the center auxiliary box. ( P. 513)
In the event that the 12-volt battery is discharged or switch operation does not
release the parking brake, the parking brake can be released manually using
the procedure below. This procedure should be performed only if necessary,
such as in an emergency.
If the switch cannot be operated even when the 12-volt battery is normal, the
parking brake system may be malfunctioning. Have the vehicle inspected by
any authorized Lexus retailer or Lexus authorized repairer, or any reliable
repairer immediately.
Before releasing the parking brake manually
Releasing the parking brake manually
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527
7
7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
If the electronic key does not operate properly
■Doors
Use the mechanical key (P. 135)
in order to perform the following
operations:
Locks all the doors
Closes the windows and moon
roof (turn and hold) *
Unlocks all the doors
Opens the windows and moon
roof (turn and hold) *
* : This setting must be customized at any authorized Lexus retailer or Lexus autho-
rized repairer, or any reliable repairer.
■Trunk
Turn the mechanical key clockwise
to open.
If communication between the electronic key and vehicle is interrupted (  P. 155) or the electronic key cann ot be used because the battery is
depleted, the smart entry & start system and wireless remote control can-
not be used. In such cases, the d oors and trunk can be opened and the
hybrid system can be started by following the procedure below.
Locking and unlocking the doors, unlocking the trunk and key linked
functions
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5287-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE) Ensure that the shift lever is in P and depress the brake pedal.
Touch the Lexus emblem side of the
electronic key to the power switch.
When the electronic key is detected, a
buzzer sounds and the power switch will
turn to ON mode.
When the smart entry & start system is
deactivated in customization setting, the
power switch will turn to ACCESSORY
mode.
Firmly depress the brake pedal and ch
eck that is shown on the multi-
information display.
Press the power switch.
In the event that the hybrid system still cannot be started, contact any authorized
Lexus retailer or Lexus authorized repairer, or any reliable repairer.
■Stopping the hybrid system
Shift the shift lever to P and press the power switch as you normally do when stopping the hybrid system.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediately when the battery is depleted. ( P. 435)
■Alarm (if equipped)
Using the mechanical key to lock the doors or trunk will not set the alarm system.
If a door or trunk are unlocked using the me chanical key when the alarm system is set,
the alarm may be triggered. ( P. 91)
■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. 218)
■When the electronic key does not work properly
●Make sure that the smart entry & start syst em has not been deactivated in the customi-
zation setting. If it is off, turn the function on.
(Customizable features: P. 561)
●Check if battery-saving mode is set. If it is set, cancel the function. (P. 154)
Starting the hybrid system
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3

5307-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
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. 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. 93)
Open the hood ( P. 401), remove
the engine compartment covers (  P. 405) and open the fuse box
cover.
Remove all of the clips.
Push the tabs on either side to
detach the lock and lift the lid off
while pulling the lock plate.
Open the exclusive jump starting
terminal cover.
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 retailer or Lexus authorized repairer,
or any reliable repairer.
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2
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2
3

5327-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE) 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 second vehicle and start the hybrid system
of your vehicle by turning the power switch to ON mode.
Make sure the “READY” indicator come s on. If the indicator does not come
on, contact any authorized Lexus retailer or Lexus authorized repairer, or any
reliable repairer.
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 retailer or Lexus authorized repairer, or any reliable repairer as soon as
possible.
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533
7-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
■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 componen ts 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 the
hybrid 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 discharged. 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 mode 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.
WARNING
■Avoiding 12-volt battery fires or explosions
Observe the following precautions to prevent 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.

5347-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■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 be
received.
●Always wash your hands after handling the 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 any authorized Lexus retailer or Lexus autho-
rized repairer, or any reliable repairer 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. 414
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in the
cooling fans or belt.
■To prevent damaging the vehicle
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 vehicle.