2010 Lexus GS450h Using The Audio System / LEXUS 2010 GS450H OWNERS MANUAL (OM30C81U)

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When trouble arises
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5-2. Steps to take in an emergency
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October 13, 2015 12:41 pm
■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 elec-
tronic key battery be replaced immediately when the battery depletes. (P. 4 9 4 )

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5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
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 call your Lexus dealer or 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 Lexus following the steps
below.
Open the trunk using the mechanical key. (
P. 5 76 )
Remove the left-hand cover in
the trunk.
Connect the jumper cables.
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.STEP1
STEP2
STEP3

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When trouble arises
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5-2. Steps to take in an emergency
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October 13, 2015 12:41 pm
■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, etc.
■When the 12 volt battery is removed or discharged
The hybrid system may not start. (
P. 4 7 1 )
Also, the intuitive parking assist must be initialized. (
P. 555)
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 battery of your vehicle.
Open and close any of the doors with the “POWER” switch is
OFF.
Maintain the engine speed on the second vehicle and turn the
“POWER” switch to the ON mode, then start the vehicle’s
hybrid system.
Make sure the “READY” light comes on. If the light does not
come on, contact your Lexus dealer.
Once the vehicle’s hybrid system has started, remove the
jumper cables in the exact reverse order in which they were
connected.
Once the hybrid system starts, have the vehicle checked at your Lexus
dealer as soon as possible.STEP4
STEP5
STEP6
STEP7
STEP8

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5-2. Steps to take in an emergency
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October 13, 2015 12:41 pm
CAUTION
■Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable
gas that may be emitted from the battery.
●Make sure the jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any part other than the intended terminal.
●Do not allow the jumper cables to come into contact with the “+” and “-” termi-
nals.
●Do not allow open flame or use matches, cigarette lighters or smoke near the
battery.
■Battery precautions
The battery contains poisonous and corrosive acidic electrolyte, while related parts
contain lead and lead compounds. Observe the following precautions when han-
dling the battery:
●When working with the battery, always wear safety glasses and take care not to
allow any battery fluids (acid) to come into contact with skin, clothing or the vehi-
cle body.
●Do not lean over the battery.
●If the 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 battery support, terminals, and other
battery-related parts.
●Do not allow children near the battery.
NOTICE
■When handling jumper cables
Be careful that the jumper cables do not become tangled in the cooling fan or any
of the belts when connecting or disconnecting them.

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When trouble arises
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5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
If your vehicle overheats
If your hybrid system overheats:
Stop the vehicle in a safe place and turn off the air conditioning
system.
Check to see if steam is coming out from under the hood.
If you see steam: 
Stop the hybrid system. Carefully lift the hood after the
steam subsides and then restart the hybrid system.
If you do not see steam:
Leave the hybrid system operating and carefully lift the
hood.
Remove the engine compartment cover. (P. 4 6 1 )
Check to see if the cooling fan is operating.
If the fan is operating: 
Wait until the engine coolant temperature gauge begins to
fall and then stop the hybrid system.
If the fan is not operating: 
Stop the hybrid system immediately and call your Lexus
dealer.
After the hybrid system has
cooled down sufficiently, check
the coolant level and inspect the
radiator core (radiator) for any
leaks.STEP1
STEP2
STEP3
STEP4
STEP5

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5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
■Overheating
In the following situations, your vehicle may be overheating.
●The engine coolant temperature gauge enters the red zone or a loss of power is
experienced.
●Steam is coming from under the hood.
●The message “HYBRID SYSTEM OVERHEAT” is displayed on the multi-infor-
mation display.
CAUTION
■To prevent an accident or injury when inspecting under the hood of your vehicle
●If steam is seen coming from under the hood, do not open the hood until the
steam has subsided. The engine compartment may be very hot, causing serious
injury such as burns.
●Keep hands and clothing away from the fan and engine drive belt while the hybrid
system is operating.
●Do not loosen the radiator cap while the hybrid system and radiator are hot.
Serious injury, such as burns, may result from hot coolant and steam released
under pressure.
Add coolant if necessary.
Water can be used in an emer-
gency measure if coolant is
unavailable. (P. 5 9 3 )
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP6

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5-2. Steps to take in an emergency
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October 13, 2015 12:41 pm
NOTICE
■When adding coolant
Wait until the hybrid system has cooled down before adding coolant.
When adding coolant, do so slowly. Adding cool coolant to a hot hybrid system too
quickly can cause damage to the hybrid system.

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5-2. Steps to take in an emergency
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If the vehicle becomes stuck
CAUTION
■When attempting to free a stuck vehicle
If you choose to rock the vehicle back and forth to free it, make sure the surround-
ing area is clear, to avoid striking other vehicles, objects or persons. The vehicle
may also lunge forward or lunge back suddenly as it becomes free. Use extreme
caution.
■When shifting the shift lever
Be careful not to shift the shift lever with the accelerator pedal depressed.
This may lead to unexpected rapid acceleration of the vehicle that may cause an
accident and result in death or serious injury.
Carry out the following procedures if the tires spin or the vehicle becomes
stuck in mud, dirt, or snow.
Stop the hybrid system. Set the parking brake and shift the shift
lever in “P”.
Remove the mud, snow, or sand from around the stuck tire.
Place wood, stones or some other material to help provide
traction under the tires.
Restart the hybrid system.
Shift the shift lever to the “D” or “R” position and carefully apply
the accelerator to free the vehicle.
Turn off TRAC/Enhanced VSC if these functions are hampering
your attempts to free the vehicle. (P. 2 1 6 )
STEP1
STEP2
STEP3
STEP4
STEP5