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5277-2. Steps to take in an emergency
7
When trouble arises
LS600hL_U(OM50E41U)
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.
Open the trunk lid and remove the 12-volt battery cover. ( P. 450)
In the event that the trunk opener cannot be used, use the mechanical key to open
the trunk. ( P. 5 2 4 )
Connect the jumper cables according to the following procedure:
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 ve hicle. Increase the engine speed
slightly and maintain at that le vel for approximately 5 minutes to
recharge the 12-volt battery of your vehicle.
Open and close any of th e doors of your vehicle with the power switch
off.
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 also call your Lexus dealer or a qualified repair shop.
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5287-2. Steps to take in an emergency
LS600hL_U(OM50E41U)
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 co mes on. If the indicator does not
come on, contact your Lexus dealer.
Once the hybrid system has started, remove the jumper cables in the
exact reverse order from wh ich they were connected.
Once the hybrid system starts, have the vehicle inspected at your Lexus
dealer 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 compon ents when the vehicle is running at a
low speed for an extended period, such as in heavy traffic.
■When the 12-volt battery is removed or discharged
The hybrid system may not start.
( P. 4 5 1 )
■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 elec-
trical appliances. If the vehicle is left for a long time, the 12-volt battery may dis-
charge, 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
●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. 9 1 )
●In some cases, it may not be possible to unlock the doors using the smart access
system with push-button start when the 12-volt battery is discharged. Use the wire-
less remote control or the mechanical key to lock or unlock the doors.
■If the 12-volt battery is discharged
The information stored in the computer will be deleted.
If the 12-volt battery is discharged, have the vehicle inspected by your Lexus dealer.
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5297-2. Steps to take in an emergency
7
When trouble arises
LS600hL_U(OM50E41U)
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 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.
■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 precau-
tions when handling the 12-volt battery:
●When working with the 12-volt battery, al ways wear safety glasses and take care
not to allow any 12-volt battery fluids (aci d) to come into contact with skin, cloth-
ing 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 th e 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 yo ur Lexus dealer 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. 4 5 3
Page 532 of 620
5307-2. Steps to take in an emergency
LS600hL_U(OM50E41U)●
The needle of the engine
coolant temperature gauge ( P. 99) enters
the red zone or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
●“Hybrid System Overheat” is shown on the multi-information display.
●Steam comes out from under the hood.
■If the needle of the engine coolant temperature gauge enters the red
zone
Stop the vehicle in a safe place an d turn off the air conditioning sys-
tem, 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.
After the hybrid system has
cooled down sufficiently,
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.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
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5317-2. Steps to take in an emergency
7
When trouble arises
LS600hL_U(OM50E41U)
The coolant level is satisfactory
if it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL”
“LOW”
Add coolant if necessary.
( P. 440)
Water can be used in an emer-
gency if coolant is unavailable.
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5327-2. Steps to take in an emergency
LS600hL_U(OM50E41U)
Start the hybrid system and turn the air conditioning system on to
check that the radiator cooling fan operates and to check for coolant
leaks from the radiator or hoses.
The fan operates when the air conditioning system is turned on immediately
after a cold start. Confirm that the fan is 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 fan may not operate in freezing temperatures.)
If the fan is not operating:
Stop the hybrid system immediately and contact your Lexus dealer.
If the fan is operating:
Have the vehicle inspected at the nearest Lexus dealer.
■If “Hybrid System Overheat” is shown on the multi-information dis-
play
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 (radia-
tor) for any leaks.Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact your
Lexus dealer.
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Page 535 of 620
5337-2. Steps to take in an emergency
7
When trouble arises
LS600hL_U(OM50E41U)
The coolant level is satisfactory
if it is between the “F” and “L”
lines on the reservoir.Reservoir
“F”
“L”
Add coolant if necessary.
( P. 440)
Water can be used in an emer-
gency if coolant is unavailable.
Start the hybrid system and check fo r 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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5347-2. Steps to take in an emergency
LS600hL_U(OM50E41U)
CAUTION
■When inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
●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.
●After the hybrid system has been turned off, check that the indicator on the
power switch and the “READY” indicator are off.
When the hybrid system is operating, the gasoline engine may automatically
start, or the cooling fan may suddenly oper ate even if the gasoline engine stops.
Do not touch or approach rotating parts such as the fan, which may lead to fin-
gers or clothing (especially a tie, a scarf or a muffler) getting caught, resulting in
serious injury.
NOTICE
■When adding engine/power control unit coolant
Add coolant slowly after the hybrid syst em has cooled down sufficiently. Adding
cool coolant to a hot hybrid system too quickly can cause da mage to the hybrid
system.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust etc.).
●Do not use any coolant additive.
●Do not loosen the coolant reservoir caps
while the hybrid system and radiator are
hot.
High temperature steam or coolant could
spray out.