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4388-2. Steps to take in an emergency
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If the hybrid system will not start
One of the following may be the cause of the problem:
● Vehicles with a smart entry & start system: The electronic key may
not be functioning properly. ( →P. 442)
● There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle. ( →P. 208)
● There may be a malfunction in the immobilizer system. (→P. 8 4 )
● There may be a malfunction in the steering lock system.
● The hybrid system may be malfunctioning due to an electrical prob-
lem such as electronic key battery depletion or a blown fuse. How-
ever, depending on the type of malfunction, an interim measure is
available to start the hybrid system. ( →P. 439)
One of the following may be the cause of the problem:
● The 12-volt battery may be discharged. (→P. 443)
● The 12-volt battery terminal connections may be loose or corroded.
( →P. 335)
Reasons for the hybrid system not starting vary depending on
the situation. Check the following and perform the appropriate
procedure:
The hybrid system will not start even though the correct starting
procedure is being followed. ( →P. 178, 182)
The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume.
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4398-2. Steps to take in an emergency
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When trouble arises
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One of the following may be the cause of the problem:
● The 12-volt battery may be discharged. (→P. 443)
● One or both of the 12-volt battery terminals may be disconnected.
( →P. 335)
Contact any authorized Toyota dealer or repairer, or another duly qualified
and equipped professional if the problem cannot be repaired, or if repair
procedures are unknown.
When the hybrid system does not start, the following steps can be
used as an interim measure to start the hybrid system if the power
switch is functioning normally.
Do not use this starting procedure except in cases of emergency.
Set the parking brake.
Shift the shift lever to P.
Turn the power switch to ACCESSORY mode.
Press and hold the power switch for about 15 seconds while
depressing the brake pedal firmly.
Even if the hybrid system can be started using the above steps, the
system may be malfunctioning. Have the vehicle inspected by any
authorized Toyota dealer or repairer, or another duly qualified and
equipped professional.
The Interior lights and headlights do not turn on, or the horn
does not sound.
Emergency start function (vehicles with a smart entry & start
system)
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4448-2. Steps to take in an emergency
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Connect the jumper cables according to the following procedure.
Connect a positive jumper cable clamp to the exclusive jump start-
ing terminal on your vehicle.
Connect the clamp on the other end of the positive cable to the pos-
itive (+) battery terminal on the second vehicle.
Connect a negative cable clamp to the negative (-) battery terminal
on the second vehicle.
Connect the clamp at the other end of the negative cable to a solid,
stationary, unpainted metallic point away from the exclusive jump
starting terminal and any moving parts as shown in the illustration.
Start the engine of the second vehicle. Increase the engine speed
slightly and maintain it at that level for approximately 5 minutes to
recharge the 12-volt battery of your vehicle.
Open and close any of the doors of your vehicle with the power
switch is in the “LOCK” position (vehicles without a smart entry &
start system) or off (vehicles with a smart entry & start system).
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4458-2. Steps to take in an emergency
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When trouble arises
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Maintain the engine speed of the second vehicle and start the
hybrid system of your vehicle by turning the power switch to “ON”
position (vehicles without a smart entry & start system) or ON mode
(vehicles with a smart entry & start system).
Make sure the “READY” indicator comes on. If the indicator does
not come on, contact any authorized Toyota 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.
Close the exclusive jump starting terminal cover, and reinstall the
fuse box cover to its original position.
When installing, first hook the fuse box cover onto the two rear
tabs.
Once the hybrid system starts, have the vehicle inspected at any
authorized Toyota 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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4468-2. Steps to take in an emergency
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■ Precautions when the 12-volt battery is discharged
● In some cases, it may not be possible to unlock the doors using entry func-
tion of the smart entry & start system immediately after the 12-volt battery
has been disconnected and reconnected. Use the wireless 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.
● Vehicles with a smart entry & start system: The power switch mode is mem-
orized by the vehicle. When the 12-volt battery 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 the
power switch was in ACCESSORY or ON mode before the 12-volt battery
was discharged, the audio system and/or air conditioning system may oper-
ate when the 12-volt battery is reconnected.
WARNING
■ Avoiding 12-volt battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flam-
mable 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 anything other than the intended ter-
minal.
● 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.
■ After recharging the 12-volt battery
Have the 12-volt battery inspected at any authorized Toyota 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.
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4488-2. Steps to take in an emergency
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If your vehicle overheats
●The high engine coolant temperature warning light (→P. 396)
comes on or flashes, or a loss of hybrid system power is experi-
enced. (For example, the vehicle speed does not increase.)
● If the hybrid system overheat warning light (→P. 400) comes on.
● Steam comes out from under the hood.
■If the high engine coolant temperature warning light comes on
or flashes
Stop the vehicle in a safe place and turn off the air conditioning
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.
After the hybrid system has
cooled down sufficiently,
inspect the hoses and radia-
tor core (radiator) for any
leaks.
Radiator
Cooling fan
If a large amount of coolant
leaks, immediately contact any
authorized Toyota dealer or
repairer, or another duly quali-
fied and equipped professional.
The following may indicate that your vehicle is overheating:
Correction procedures
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Page 450 of 492
4508-2. Steps to take in an emergency
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■If the hybrid system overheat warning light comes on
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 fan
If a large amount of coolant
leaks, immediately contact any
authorized Toyota dealer or
repairer, or another duly quali-
fied and equipped professional.
The coolant level is satisfac-
tory if it is between the “F”
and “L” lines on the reservoir.
Reservoir
“F” line
“L” line
Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
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4518-2. Steps to take in an emergency
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When trouble arises
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Start the hybrid system and check for the hybrid system overheat
warning light.
If the warning light does not go off:
Stop the hybrid system and contact any authorized Toyota dealer or
repairer, or another duly qualified and equipped professional.
If the warning light goes off:
Have the vehicle inspected at the nearest authorized Toyota dealer
or repairer, or another duly qualified and equipped professional.
WARNING
■ 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, caus-
ing serious injuries such as burns.
● Check that the “READY” indicator is off.
● On hybrid vehicles, the gasoline engine may automatically start, or the
cooling fan may suddenly operate 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.
● Do not loosen the coolant reservoir cap while the hybrid system and radia-
tor are hot.
Serious injuries, such as burns, may result from hot coolant and steam
released under pressure.
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