Page 430 of 596

4307-3. Do-it-yourself maintenance
PRIUS c_U (OM52J11U)■
When disconnecting the 12- volt battery terminals
Always disconnect the negative (-) terminal first.
■ After recharging/reconnecting the 12-vo lt battery (vehicles with a smart
key system)
● Unlocking the doors using the smart key system may not be possible 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 doors.
● Start the hybrid system with the “POWER” switch in ACCESSORY mode.
The hybrid system may not start with the “POWER” switch turned off. How-
ever, the hybrid system will operat e normally from the second attempt.
● The “POWER” switch mode is recorded by the vehicle. If the 12-volt battery
is reconnected, the vehicle will return the “POWER” switch mode to the sta-
tus it was in before the 12-volt battery was disconnected. Make sure to turn
off the power before disconnect the 12-volt battery. Take extra care when
connecting the 12-volt battery if the “POWER” switch mode prior to dis-
charge 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 acid 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 with 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 battery.
● 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 charge the 12-
volt battery in a garage or closed room where there is insufficient ventila-
tion.
Page 439 of 596

4397-3. Do-it-yourself maintenance
7
Maintenance and care
PRIUS c_U (OM52J11U)
WARNING
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as
dangerous handling characteristics, which may lead to an accident
resulting in death or serious injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Toyota.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply
tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have b een used on another vehicle.
Do not use tires if you do not know how they were used previously.
●Do not tow if your vehicle has a compact spare tire installed.
■When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first
adjusting the tire inflation pressure to the specified level. Otherwise, the
tire pressure warning light may not come on even if the tire inflation
pressure is low, or it may come on when the tire inflation pressure is
actually normal.
Page 481 of 596

4818-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U (OM52J11U)
*3: Driver's seat belt buzzer: Vehicles without a smart key system: The driver’s seat belt buzzer sounds
to alert the driver that his or her seat belt is not fastened. Once the engine
switch is turned to the “ON” position, the buzzer sounds for 6 seconds. If
the vehicle reaches a speed of 12 mph (20 km/h), the buzzer sounds once.
If the seat belt is still unfastened after 24 seconds, the buzzer will sound
intermittently for 10 seconds. Then, if the seat belt is still unfastened, the
buzzer will sound in a different tone for 20 more seconds.
Vehicles with a smart key system: The driver’s seat belt buzzer sounds to
alert the driver that his or her seat belt is not fastened. Once the “POWER”
switch is turned to ON mode, the buzzer sounds for 6 seconds. If the vehi-
cle reaches a speed of 12 mph (20 km/h), the buzzer sounds once. If the
seat belt is still unfastened after 24 seconds, the buzzer will sound intermit-
tently for 10 seconds. Then, if the seat belt is still unfastened, the buzzer
will sound in a different tone for 20 more seconds.
Front passenger’s seat belt buzzer:
The front passenger’s seat belt buzzer sounds to alert the front passenger
that his or her seat belt is not fastened. The buzzer sounds once if the
vehicle reaches a speed of 12 mph (20 km/h). If the seat belt is still unfas-
tened after 24 seconds, the buzzer will sound intermittently for 10 seconds.
Then, if the seat belt is still unfastened, the buzzer will sound in a different
tone for 20 more seconds.
Page 483 of 596

4838-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U (OM52J11U)■
If the tire pressure warning system is not functioning
→P. 437
■
If the tire pressure warning light frequently comes on after blinking
for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1
minute when the engine switch is turned to the “ON” position (vehicles
without a smart key system) or the “POWER” switch is turned to ON
mode (vehicles with a smart key system ), have it checked by your Toyota
dealer.
■ Customization that can be co nfigured at Toyota dealer
The vehicle speed linked seat belt reminder buzzer can be disabled. (Cus-
tomizable features →P. 556) However, Toyota recommends that the seat belt
reminder buzzer be operational to alert the driver and front passenger when
seat belts are not fastened.
■ Warning buzzer
In some cases, the buzzer may not be heard because of noisy place or an
audio sound.
WARNING
■When the electric power steerin g system warning light comes on
The steering wheel may become extremely heavy.
When steering wheel operations are heavier than usual, grip the steering
wheel firmly and operate it using more force than usual.
■
If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could
cause a loss of vehicle control and result in death or serious injury.
●Stop your vehicle in a safe place as soon as possible. Adjust the tire
inflation pressure immediately.
●If the tire pressure warning light co mes on even after tire inflation pres-
sure adjustment, it is probable that you have a flat tire. Check the tires.
If a tire is flat, change it with the spare tire and have the flat tire
repaired by the nearest Toyota dealer.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate,
you could lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.
Page 492 of 596

4928-2. Steps to take in an emergency
PRIUS c_U (OM52J11U)Indicates that the driver’s door was opened with
the shift position in N, D or B
A buzzer also sounds.
→ Shift the shift lever to P.
Indicates that the accelerator pedal is depressed
while the shift position is in N A buzzer also sounds.
→ Release the accelerator pedal and shift the
shift lever to D, B or R.
Indicates that the engine switch is turned to the
“ACC” or “LOCK” position (vehicles without a
smart key system) or the “POWER” switch is
turned to ACCESSORY mode or turned off (vehi-
cles with a smart key system) and the driver’s
door is opened while the lights are turned on A buzzer also sounds.
→ Turn the lights off.
Indicates that the EV drive mode is not avail-
able
*2
The reason the EV drive mode is not available
(the vehicle is idling, battery charge is low,
speed is higher than the EV drive mode operat-
ing speed range, accelerator pedal is
depressed too much) may be displayed.
A buzzer also sounds.
→ Use the EV drive mode when it becomes
available.
Warning messageDetails/Actions
(Flashes)
(Flashes)
(Flashes)
Page 499 of 596
4998-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U (OM52J11U)
⎯⎯
Power was turned off due to the
automatic power off function.
→Next time when starting
the hybrid system,
increase the engine speed
slightly and maintain that
level for approximately 5
minutes to recharge the
12-volt-battery.
Once⎯
The electronic key has a low
battery.
→Replace the electronic key
battery. ( →P. 448)
Once⎯
The driver's door was opened
and closed with the “POWER”
switch turned off and then the
“POWER” switch was put in
ACCESSORY mode twice with-
out the hybrid system being
started.
→Press the “POWER”
switch while depressing
the brake pedal.
During a hybrid system starting
procedure in the event that the
electronic key was not function-
ing properly
(→P. 516), the “POWER” switch
was touched with the electronic
key.
→ Press the “POWER”
switch within 10 seconds
of the buzzer sounding.
Interior
buzzerExterior buzzerWarning messageDetails/Actions
(Flashes)
Page 515 of 596

5158-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U (OM52J11U)
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( →P. 518)
● One or both of the 12-volt batter y terminals may be disconnected.
( → P. 428)
Contact your Toyota dealer 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 case 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.
Even if the hybrid system can be started using the above steps, the
system may be malfunctioning. Have the vehicle inspected by your
Toyota dealer.
The interior lights and headlight s do not turn on, or the horn
does not sound.
Emergency start function (vehicles with a smart key system)
1
2
3
4
Page 516 of 596

5168-2. Steps to take in an emergency
PRIUS c_U (OM52J11U)
Use the mechanical key (→P.
121) in order to perform the fol-
lowing operations (driver’s door
only):
Unlocks the doors
Locks all the doors
Turning the key rearward unlocks
the driver’s door. Turning the key
once again within 5 seconds
unlocks the other doors.
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Toyota emblem side
of the electronic key to the
“POWER” switch.
When the electronic key is
detected, a buzzer sounds and the
“POWER” switch will turn to ON
mode.
When the smart key system is
deactivated in customization set-
ting, the power switch will turn to
ACCESSORY mode.
If the electronic key do es not operate prop-
erly (vehicles with a smart key system)
If communication between the electronic key and vehicle is
interrupted (→P. 142) or the electronic key cannot be used
because the battery is depleted, the smart key system and wire-
less remote control cannot be used. In such cases, the doors
can be opened and the hybrid system can be started by follow-
ing the procedure below.
Locking and unlocking the doors
1
2
Starting the hybrid system
1
2