2007 Lexus GS450h Specifications / LEXUS 2007 GS450H FROM JULY 2006 PROD. OWNER'S MANUAL (OM30A05U)

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5-2. Steps to take in an emergency
■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 compon ents 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. 3 8 0 )
Also, the following systems must be initialized.
●Po w e r w i n d o w s (P. 5 1 )
●Variable gear ratio steering (P. 1 5 3 )
●Tire pressure warning system (P. 3 8 5 )
●Intuitive parking assist (P. 1 5 3 )
Maintain the engine speed on th e second vehicle and turn the
power switch to the “IG-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.STEP5
STEP6
STEP7

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5-2. Steps to take in an emergency
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.
■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 we ar 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.

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5-2. Steps to take in an emergency
NOTICE
■To prevent damaging the vehicle
Hybrid vehicles cannot be push-started.
■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
If your vehicle overheats
■Electric motor (traction motor) and inverter
If the message “HYBRID SYSTEM OVERHEAT” is displayed on the
multi-information display.
■ Gasoline engine
If the needle of the engine co olant temperature gauge enters the
red zone, the gasoline engine has probably overheated.
Observe the following steps:
Stop the vehicle in a safe place and turn off the automatic 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. 370)
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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5-2. Steps to take in an emergency
■Overheating
In the following situations, your vehicle may be overheating.
●The message “HYBRID SYSTEM OVERHEAT” is displayed on the multi-infor-
mation display.
●The engine coolant temperature gauge enters the red zone or a loss of power is
experienced.
●Steam is coming from under the hood.
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 required.
Water can be used in an emer-
gency measure if coolant is
unavailable. ( P. 4 9 0 )
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
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
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.
NOTICE
■To avoid damaging the transmission and other components
●Avoid spinning the wheels and racing the hybrid system.
●If the vehicle remains stuck after trying these procedures, the vehicle may require
towing to be freed.
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 ot her material to help provide
traction under the tires.
Restart the hybrid system.
Turn off TRAC. (  P. 166)
Carefully apply the accelerator to free the vehicle.STEP1
STEP2
STEP3
STEP4
STEP5
STEP6

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5-2. Steps to take in an emergency