Lexus GS450h 2008 Using other driving systems / LEXUS 2008 GS450H OWNER'S MANUAL (OM30A96U)

5
When trouble arises
531
5-2. Steps to take in an emergency
GS_HV_U
December 12, 2007 3:50 pm
If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk and key linked
functions
Doors Using the mechanical key in order
to perform the following opera-
tions:
Locks all doors
Closes the windows/moon roof
(turn and hold)
Unlocks the door
Turning the key rearward unlocks
the driver’s door.
Turning the key once again unlocks
the other doors.
Opens the windows/moon roof
(turn and hold)
If communication between the electron ic key and vehicle is interrupted
(
P. 39) or the electronic key cannot be used because the battery is
depleted, the smart access system with push-button start and wireless
remote control cannot be used. In such cases, the doors and trunk can be
opened or the hybrid system can be started by following the procedure
below.

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5-2. Steps to take in an emergency
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December 12, 2007 3:50 pm
Tr u n kTurn the mechanical key clock-
wise to open.
Changing “POWER” switch modes and starting the hybrid system
Put the shift lever in “P” and apply the brakes. Touch the Lexus emblem side of
the electronic key to the
“POWER” switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
the “POWER” switch if any of the
doors is opened and closed while
the key is touched to the switch.
STEP1
STEP2

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5-2. Steps to take in an emergency
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December 12, 2007 3:50 pm
To change the “POWER” switch modes: Within 10 seconds of the
buzzer sounding, release the brake pedal and press the
“POWER” switch. Modes can be changed each time the switch is
pressed. (
P. 1 3 9 )
To start the hybrid system: Press the “POWER” switch within 10
seconds after the buzzer soun ds, keeping the brake pedal
depressed.
If the “POWER” switch still cannot be operated, contact your Lexus
dealer.
■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 the temporary measure, it is recommended that the
electronic key battery be replaced i mmediately when the battery depletes.
(  P. 4 5 4 )
STEP3

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5-2. Steps to take in an emergency
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December 12, 2007 3:50 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 3 2 )
Remove the left-hand cover in
the trunk.
Connecting the jumper cables.STEP1
STEP2
STEP3

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5-2. Steps to take in an emergency
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December 12, 2007 3:50 pm
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.
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 door s with the “POWER” switch is
OFF.
Maintain the engine speed on th e second vehicle and turn the
“POWER” switch to the ON mo de, then start the vehicle’s
hybrid system.
Make sure the “READY” light co mes 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.
STEP3
STEP4
STEP5
STEP6
STEP7

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5-2. Steps to take in an emergency
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December 12, 2007 3:50 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 3 1 )
Also, the following systems must be initialized.
●Tire pressure warning system (P. 4 3 6 )
●Intuitive parking assist (P. 5 1 2 )
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 pa rt 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.

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5-2. Steps to take in an emergency
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December 12, 2007 3:50 pm
CAUTION
■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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5-2. Steps to take in an emergency
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December 12, 2007 3:50 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 and carefully lift the hood.
If you do not see steam: Leave the hybrid system running and carefully lift the hood.
Remove the engine compartment cover. ( P. 421)
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 immed iately and call your local
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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When trouble arises
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5-2. Steps to take in an emergency
GS_HV_U
December 12, 2007 3:50 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 in specting under the hood of your vehicle
●Keep hands and clothing away from the fan and engine drive belt while the hybrid
system is running.
●Do not loosen the radiator cap while the hybrid system and radiator are hot. 
Serious injury, such as burns, may resu lt 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 4 8 )
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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December 12, 2007 3:50 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.