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7-2. Steps to take in an emergency
If  the 12-volt batter y is discharged
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 foll owing the
steps below.
Open the hood. ( P. 515)
Remove the engine cover.
Pull  up  the  both  ends  of  the  cover
vertically.
The  following  procedures  may  be  used  to  start  the  hybrid  sys-
tem if the vehicle’s 12-volt battery is discharged.
You can also call your Toyota de aler or a qualified repair shop.
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6517-2. Steps to take in an emergency
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7
When trouble arises
Connect the jumper cables according to the following procedure:Connect a positive jumper cable clamp to the positive (+) batte ry
terminal on your vehicle.
Connect  the  clamp  on  the  other  end  of  the  positive  cable  to  the
positive (+) battery termi nal on the second vehicle.
Connect a negative cable clamp to the negative (-) battery term i-
nal on the s econd vehicle.
Connect  the  clamp  at  the  other  e nd  of  the  negative  cable  to  a
solid,  stationary,  unpainted  metallic  point  away  from  the  12-vo lt
battery and any movin g parts, as shown in the illustration.
Start  the  engine  of  the  second  v ehicle.  Increase  the  engine  speed
slightly  and  maintain  at  that  lev el  for  approximately  5  minutes to
recharge the 12-volt battery of your vehicle.
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  comes  on.  If  the  indicator  ligh t
does not come on, contac t your Toyota dealer.3
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6527-2. Steps to take in an emergency
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Once  the  hybrid  system  has  started,  remove  the  jumper  cables  in
the exact reverse order from which they were connected.
To  install  the  engine  cover,  conduct  the  removal  procedure  in
reverse.  After  installing,  check  that  the  fixed  pins  are  inserted
securely.
Once  the  hybrid  system  starts,  have  the  vehicle  inspected  at  yo ur
Toyota dealer as soon as possible.
■ When opening the cover of the  positive (+) battery terminal
P. 525
■ 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 s ystem 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 .
■ When the 12-volt battery  is removed or discharged
● Information  stored  in  the  ECU  is  cleared.  When  the  12-volt  batt ery  is
depleted, have the vehicle inspected at your Toyota dealer.
● Some systems may require initialization. ( P. 701)
■ When removing the 12-vo lt battery terminals
When the 12-volt battery terminals are removed, the information  stored in the
ECU  is  cleared.  Before  removing  the  12-volt  battery  terminals,  contact  your
Toyota dealer.
■ Charging the 12-volt battery
The electricity stored in the 12-volt battery will discharge gr adually even when
the vehicle is not in use, due to natural discharge and the dra ining effects of
certain  electrical  appliances.  If  the  vehicle  is  left  for  a  lon g  time,  the  12-volt
battery  may  discharge,  and  the  hybrid  system  may  be  unable  to  s tart.  (The
12-volt battery recharges automatically while the hybrid system  is operating.)
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6547-2. Steps to take in an emergency
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WARNING
■When removing the 12-vo lt battery terminals
Always remove the negative (-) terminal first. If the positive  (+) terminal con-
tacts  any  metal  in  the  surrounding  area  when  the  positive  (+)  terminal  is
removed, a spark may occur, leading to a fire in addition to el ectrical shocks
and death or serious injury.
■ Avoiding 12-volt batte ry fires or explosions
Observe  the following  precautions  to prevent accidentally ignit ing  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 any other than the in tended terminal.
● 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 in to contact
with each other.
● Do  not  smoke,  use  matches,  cigarette  lighters  or  allow  open  fla me  near
the 12-volt battery.
■ 12-volt battery precautions
The  12-volt  battery  contains  poisonous  and  corrosive  acidic  ele ctrolyte,
while related parts contain lead and lead compounds. Observe th e following
precautions when handling the 12-volt battery:
● When  working  with  the  12-volt  battery,  always  wear  safety  glass es  and
take  care  not  to  allow  any  battery  fluids  (acid)  to  come  into  c ontact  with
skin, clothing or the vehicle body.
● Do not lean over the 12-volt battery.
● In  the  event  that  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 medica l attention
can be received.
● Always wash your hands after handling the 12-volt battery suppo rt, termi-
nals, and other battery-related parts.
● Do not allow children near the 12-volt battery. 
     
        
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6557-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)
7
When trouble arises
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not beco me entan-
gled in the cooling fans, etc.