Page 431 of 596

4317-3. Do-it-yourself maintenance
7
Maintenance and care
PRIUS c_U■
After recharging/reconnecting the 12-volt battery (vehicles wit h a smart
key system)
● Unlocking the doors using the smart key system may not be possi ble imme-
diately after reconnecting the 12-volt battery. If this happens, use the wire-
less remote control or the mechanical key to lock/unlock the do ors.
● Start the hybrid system with the power switch in ACCESSORY mode . The
hybrid system may not start with the power switch turned off. However, the
hybrid system will operate normally from the second attempt.
● The power switch mode is recorded by the vehicle. If the 12-vol t battery is
reconnected, the vehicle will return the power switch mode to t he status it
was in before the 12-volt battery was disconnected. Make sure t o turn off
the power before disconnect the 12-volt battery. Take extra car e when con-
necting the 12-volt battery if the power switch mode prior to d ischarge is
unknown.
If the system will not start even after multiple attempts, contact your Toyota
dealer.
WARNING
■ Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric a cid and may
produce hydrogen gas which is flammable and explosive. To reduce the risk
of death or serious injury, take the following precautions while working on or
near the 12-volt battery:
● Do not cause sparks by touching the 12-volt battery terminals w ith tools.
● Do not smoke or light a match near the 12-volt battery.
● Avoid contact with eyes, skin and clothes.
● Never inhale or swallow electrolyte.
● Wear protective safety glasses when working near the 12-volt ba ttery.
● Keep children away from the 12-volt battery.
■ Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charg e the 12-
volt battery in a garage or closed room where there is insuffic ient ventila-
tion.
Page 432 of 596

4327-3. Do-it-yourself maintenance
PRIUS c_U
WARNING
■How to recharge the 12-volt battery
Slow charge (5 A or less). Quick charge 15 A MAX.
■ Emergency measures regarding electrolyte
● If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and ge t immedi-
ate medical attention. If possible, continue to apply water wit h a sponge or
cloth while traveling to the nearest medical facility.
● If electrolyte gets on your skin
Wash the affected area thoroughly. If you feel pain or burning, get medical
attention immediately.
● If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the cloth-
ing and follow the procedure above if necessary.
● If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medical attention
immediately.
■ When disconnecting the 12-volt battery
Do not disconnect the negative (-) terminal on the body side. T he discon-
nected negative (-) terminal may touch the positive (+) termina l, which may
cause a short and result in death or serious injury.
■ When replacing the 12-volt battery
Use a 12-volt battery designed for this vehicle. Failure to do so may cause
gas (hydrogen) to enter the passenger compartment, causing a fire or
explosion.
For replacement of the 12-volt battery, contact your Toyota dea ler.
NOTICE
■When recharging th e 12-volt battery
Never recharge the 12-volt battery while the hybrid system is o perating.
Also, be sure all accessories are turned off.
Page 493 of 596
4938-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_UIndicates that the EV drive mode has been auto-
matically canceled
*2
The reason the EV drive mode is not available
(the battery charge is low, speed is higher than
the EV drive mode speed range, accelerator
pedal is depressed too much) may be dis-
played.
A buzzer also sounds.
Drive the vehicle for a while.
Indicates a malfunction in the vehicle’s charging
system A buzzer also sounds.
Immediately stop the vehicle in a safe place
and contact your Toyota dealer.
Indicates that the TRAC (Traction Control) sys-
tem has been deactivated
Turn the TRAC on. ( P. 264)
Warning messageDetails/Actions
(Flashes 3
times)
Page 522 of 596

5228-2. Steps to take in an emergency
PRIUS c_U
■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 .
■ Precautions when the 12-volt batte ry is discharged (vehicles with a
smart key system)
● In some cases, it may not be possible to unlock the doors using the smart
key system immediately after the 12-volt battery has been disco nnected 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.
● The power switch mode is memorized by the vehicle. When the 12- volt bat-
tery 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 bat-
tery was discharged, the audio system and/or air conditioning system may
operate when the 12-volt battery is reconnected.
■ 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. 563)
■ 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.)
Page 524 of 596

5248-2. Steps to take in an emergency
PRIUS c_U
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.
■ After recharging the 12-volt battery
Have the 12-volt battery inspected at your Toyota dealer as soo n as possi-
ble.
If the 12-volt battery is deteriorating, continued use may caus e the 12-volt
battery to emit a malodorous gas, which may be detrimental to the health of
passengers.
Page 539 of 596
5399-1. Specifications
9
Vehicle specifications
PRIUS c_U
Ignition system
Spark plug
Make
GapDENSO FK16R-A8
0.03 in. (0.8 mm)
NOTICE
■
Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark pl ug gap.
Electrical system
12-volt battery
Open voltage at
68 F (20 C): 12.0 V or higher
If the voltage is lower than the standard value,
charge the battery.
(Voltage checked 20 minutes after the hybrid sys-
tem and all the lights are turned off)
Charging rates
Quick charge
Slow charge 15 A max.
5 A max.