2015 TOYOTA PRIUS C key battery

4738-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U (OM52E68U)
One of the following may be the cause of the problem:
●Vehicles with a smart key system: The electronic key may not be
functioning properly. ( P. 476)
● There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle. ( P. 214)
● Vehicles with immobilizer system: There may be a malfunction in
the immobilizer system. ( P. 82)
● There may be a malfunction in the steering lock system.
● Vehicles with a smart key system: The hybrid system may be mal-
functioning due to an electrical problem such as an open circuit or a
blown fuse. However, depending on the type of malfunction, an
interim measure is available to start the hybrid system. ( P. 474)
One of the following may be the cause of the problem:
● The 12-volt battery may be discharged. ( P. 478)
● The 12-volt battery terminal connections may be loose or corroded.
( P. 394)
One of the following may be the cause of the problem:
● The 12-volt battery may be discharged. ( P. 478)
● One or both of the 12-volt battery terminals may be disconnected.
( P. 394)
Contact your Toyota dealer if the problem cannot be repaired, or if repair
procedures are unknown.
If the hybrid system will not star t
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. 182, 186)
The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume.
The interior lights and headlights do not turn on, or the horn
does not sound.

4768-2. Steps to take in an emergency
PRIUS c_U (OM52E68U)
Use the mechanical key (P. 1 1 9 )
in order to perform the following
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 does not operate prop-
erly (vehicles with a smar t key system)
If communication between the electronic key and vehicle is
interrupted ( P. 140) 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

4778-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U (OM52E68U)
Firmly depress the brake pedal and check that is displayed
on the multi-information display.
Press the “POWER” switch.
In the event that the “POWER” switch still cannot be operated, contact
your Toyota dealer.
■ Stopping the hybrid system
Shift the shift lever to P and press the “POWER” switch as you normally do
when stopping the hybrid system.
■ Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the
electronic key battery be replaced imm ediately when the battery is depleted.
(  P. 413)
■ Changing “POWER” switch modes
Release the brake pedal and press the “POWER” switch in above.
The hybrid system does not start and modes will be changed each time the
switch is pressed. ( P. 187)
■ If the doors cannot be locked or unlocked by the smart key system
Lock and unlock the doors by the mechanical key or wireless remote control.
■ When the electronic key does not work properly
●Make sure that the smart key system has not been deactivated in the cus-
tomization setting. If it is off, turn the function on.
(Customizable features P. 514)
● Check if battery-saving mode is set. If it is set, cancel the function.
(P. 139)
3
4
3

4798-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U (OM52E68U)
Connect the jumper cables according to the following procedure:Connect a positive jumper cable clamp to the exclusive jump
starting terminal on your vehicle.
Connect the clamp on the other end of the positive cable to the
positive (+) battery terminal on the second vehicle.
Connect a negative cable clamp to the negative (-) battery termi-
nal 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 that level for approximately 5 minutes to
recharge the 12-volt battery of your vehicle.
Vehicles with a smart key system only: Open and close any of the
doors of your vehicle with the “POWER” switch off.
Vehicles without a smart key system:
Maintain the engine speed of the second vehicle and start the
hybrid system of your vehicle by turning the engine switch to the
“ON” position.
Vehicles with a smart key system:
Maintain the engine speed of the second vehicle and start the
hybrid system of your vehicle by turning the “POWER” switch to ON
mode.3
1
2
3
4
4
5
6

4808-2. Steps to take in an emergency
PRIUS c_U (OM52E68U)
Make sure the “READY” indicator comes on. If the indicator does
not come on, contact your Toyota dealer.
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 your
Toyota 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 components when the vehicle is running
at a low speed for an extended period, such as in heavy traffic.
■ Precautions when the 12-volt battery 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 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.
● The “POWER” switch mode is memorized 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 sy stem and/or air conditioning system
may operate when the 12-volt battery is reconnected.
■ 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.)
7
8
9

536
PRIUS c_U (OM52E68U)
What to do if... (Troubleshooting)
What to do if... (Troubleshooting)
●If you lose your keys or mechanical keys, new genuine keys or mechanical
keys can be made by your Toyota dealer. (P. 120)
●If you lose your keys or electronic keys, the risk of vehicle theft increases
significantly. Contact your Toyota dealer immediately. ( P. 123)
●Is the key battery weak or depleted? (P. 413)
●Vehicles with a smart key system:
Is the “POWER” switch in ON mode?
When locking the doors, turn the “POWER” switch off. ( P. 187)
●Vehicles with a smart key system:
Is the electronic key left inside the vehicle?
When locking the doors, make sure that you have the electronic key on
your person.
●The function may not operate properly due to the condition of the radio
wave. (P. 140)
If you have a problem, check the following before contacting
your Toyota dealer.
The doors cannot be locked, unlocked, opened or closed
You lose your keys
The doors cannot be locked or unlocked

537What to do if... (Troubleshooting)
PRIUS c_U (OM52E68U)
●Is the child-protector lock set?
The rear door cannot be opened from inside the vehicle when the lock is
set. Open the rear door from outside and then unlock the child-protector
lock. ( P. 128)
●Is the shift lever in P? ( P. 182)
●Is the steering wheel unlocked? ( P. 184)
●Is the 12-volt battery discharged? ( P. 478)
●Did you press the “POWER” switch while firmly depressing the brake
pedal? (P. 186)
●Is the shift lever in P? ( P. 189)
●Is the electronic key anywhere detectable inside the vehicle?
(P. 138)
●Is the steering wheel unlocked? ( P. 189)
●Is the electronic key battery weak or depleted?
In this case, the hybrid system can be started in a temporary way.
(P. 476)
●Is the 12-volt battery discharged? ( P. 478)
The rear door cannot be opened
If you think something is wrong
The hybrid system does not start
(vehicles without a smart key system)
The hybrid system does not start
(vehicles with a smart key system)

543Alphabetical index
PRIUS c_U (OM52E68U)
Child safetyAirbag precautions .................. 40
Child-protectors .................... 128
Child restraint system ............. 57
How your child should
wear the seat belt ................. 32
Installing child restraints ......... 61
Moon roof precautions .......... 164
Power window lock switch .... 158
Power window precautions ... 161
Removed key battery precautions......................... 415
Seat belt extender precautions........................... 36
Seat belt precautions .............. 34
Seat heater precautions........ 348
12-volt battery precautions................. 396, 481
Cleaning Exterior ................................. 366
Interior................................... 369
Seat belts .............................. 369
Clock........................................... 96
Coat hooks ............................... 360
Condenser................................ 391
Console box ............................. 353
Cooling system Hybrid system overheating ... 483
Cord hook................................. 250
Cruise control .......................... 218
Cup holders.............................. 355
Curtain shield airbags ............... 38
Customizable features ............ 514 Daytime running light
system.................................... 203
Defogger Rear window ......................... 342
Side mirrors .......................... 342
Dimension ................................ 490
Dinghy towing.......................... 181
Display Energy flow ........................... 107
Multi-information display ......... 94
Trip information....................... 94
Warning message................. 449
Do-it-yourself maintenance .... 379
Doors Back door ............................. 133
Door lock .............................. 127
Door windows ....................... 158
Rear door child protector ...... 128
Side doors ............................ 124
Side mirrors .......................... 156
Driver’s seat belt reminder light ........................................ 443
Driving
Break-in tips.......................... 168
Correct posture ....................... 26
Procedures ........................... 166
Winter driving tips ................. 241D