Lexus GS300h 2013 Owner's Manual

9147-2. Steps to take in an emergency
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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 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 appliances. 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.)
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7 7-2. Steps to take in an emergency
When trouble arises
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When recharging or replacing the 12-volt battery
For vehicles with an alarm: 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. 99)
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 wire-
less 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 bat-
tery 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 discharged, be especially careful when reconnecting the 12-volt bat-
tery.
CAUTION
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 termi-
nal.
Do not allow the other end of the jumper cable connected to the “+” termi-
nal 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.

9167-2. Steps to take in an emergency
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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 follow-
ing 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 12-volt battery fluids (acid) to come into con-
tact 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, 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 the 12-volt battery support, termi-
nals, 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 dealer or
repairer, or another duly qualified and equipped professional 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. 7 5 3

9177-2. Steps to take in an emergency
7
When trouble arises
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If your vehicle overheats
If the needle of the engine coolant temperature gauge enters the
red zone
Stop the vehicle in a safe place and turn off the air condition-
ing system, 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.
The following may indicate that your vehicle is overheating.
The needle of the engine coolant temperature gauge (P. 109)
enters the red zone or a loss of hybrid system power is experi-
enced. (For example, the vehicle speed does not increase.)
“Hybrid System Overheat” (P. 856) is shown on the multi-
information display.
Steam comes out from under the hood.
Correction procedures
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9187-2. Steps to take in an emergency
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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 coolant level is satisfactory if it is between the “FULL”
and “LOW” lines on the reservoir.
Reservoir
“FULL”
“LOW”
Coolant inlet cap
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9197-2. Steps to take in an emergency
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When trouble arises
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Add coolant if necessary. (P. 923)
Water can be used in an emergency if engine coolant is unavailable.
Start the hybrid system and turn the air conditioning system on
to check that the radiator cooling fans operate and to check for
coolant leaks from the radiator or hoses.
The fans operate when the air conditioning system is turned on immedi-
ately 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 system on and off repeatedly. (The fans may not operate in
freezing temperatures.)
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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9207-2. Steps to take in an emergency
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If “Hybrid System Overheat” is shown on the multi-information
display
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 radiator 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 “F”/
“FULL” and “L”/“LOW” lines on the reservoir.
Reservoir
“F”/“FULL”
“L”/“LOW”
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9217-2. Steps to take in an emergency
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When trouble arises
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9227-2. Steps to take in an emergency
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Add coolant if necessary.
Water can be used in an emergency if power control unit coolant is
unavailable.
Start the hybrid system and check for the multi-information
display.
If the message does not disappear:
Stop the hybrid system and contact your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest Lexus dealer.
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923
7 7-2. Steps to take in an emergency
When trouble arises
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When adding coolant
Add coolant in accordance with the following procedure.
Remove caps A and B.
Add coolant through the inlet of cap A up to the B-line, and then install cap
A.
Add coolant through the inlet of cap B until it is full, and then install cap B.
GS300h only: When installing cap B, apply coolant to the O-ring on the
end of cap B.
Cap A
Cap B
B-line (Target fill line)
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