2012 TOYOTA PRIUS key battery

454
4-3. Do-it-yourself maintenance
Electronic key batter y
Replace the battery with a new one if it is depleted.
■You will need the following items:
●Flathead screwdriver
● Lithium battery CR1632
■ Replacing the battery
Take out the mechanical key.
Remove the cover.
To prevent damage, cover the
tip of the screwdriver with a
rag.
Remove the depleted battery.
Insert a new battery with the
“+” terminal facing up.
When installing, reverse the steps listed.
STEP 1
STEP 2
ITO43P194
STEP 3
STEP 4

455
4-3. Do-it-yourself maintenance
4
Maintenance and care
■
Use a CR1632 lithium battery
●Batteries can be purchased at your Toyota dealer, local electrical appli-
ance shops or camera stores.
● Replace only with the same or equivalent type recommended by the
manufacturer.
● Dispose of used batteries according to local laws.
■ If the electronic key battery is depleted
The following symptoms may occur:
●The smart key system and wireless remote control will not function prop-
erly.
● The operational range will be reduced.
CAUTION
■Removed battery and other parts
Keep away from children. These parts are small and if swallowed by a child,
they can cause choking. Failure to do so could result in death or serious
injury.
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents:
●Always work with dry hands.
Moisture may cause the battery to rust.
● Do not touch or move any other component inside the remote control.
● Do not bend either of the battery terminals.

461
4-3. Do-it-yourself maintenance
4
Maintenance and care
FUSEAmpereCircuit
32 MIR HTR 10A Outside rear view mirror defoggers
33 RAD NO.1 15A Audio system, navigation system
34 DOME 10ADoor courtesy lights, luggage
compartment light, personal light,
interior light, foot lights, vanity
lights, inside rear view mirror,
garage door opener
35 ECU-B 7.5ASmart key system, personal lights,
gauges and meters, emergency
flashers
36 H-LP LH HI 10A Left-hand headlight (high beam)
37 H-LP RH HI 10A Right-hand headlight (high beam)
38 EFI NO.2 10AMultiport fuel injection system/
sequential multiport fuel injection
system
39 IGCT NO.3 10A Cooling system
40 SPARE 30A Spare fuse
41 SPARE 10A Spare fuse
42 SPARE 7.5A Spare fuse
43 EFI MAIN 20AMultiport fuel injection system/
sequential multiport fuel injection
system, cooling system, EFI NO.2
44 BATT FAN 10A Battery cooling fan
45 IG2 20AMultiport fuel injection system/
sequential multiport fuel injection
system, MET, IGN, power man-
agement system

When trouble arises5
483
5-1. Essential informationEmergency flashers ......... 484
If your vehicle needs to be towed ........................ 485
If you think something is wrong ......................... 492
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer
sounds ........................... 493
If a warning message is displayed .................... 507
If you have a flat tire......... 523
If the hybrid system will not start .......................... 538
If you lose your keys ........ 540
If the electronic key does not operate properly....... 541
If the 12-volt battery is discharged ..................... 543
If your vehicle overheats ....................... 549
If the vehicle becomes stuck .............................. 554
If your vehicle has to be stopped in an
emergency ..................... 556

5
When trouble arises
485
5-1. Essential information
If your vehicle needs to be towed
Before towingThe following may indicate a problem with your hybrid transmission.
Contact your Toyota dealer before towing.
● The hybrid system is operating but the vehicle will not move.
● The vehicle makes an abnormal sound.
If there is a malfunction in the P position control system, the smart
key system or the immobilizer system , or if the 12-volt battery is dis-
charged, the vehicle cannot be tow ed with the front wheels on the
ground, as the front wheels may be locked. In this case, transport the
vehicle with both front wheels or all four wheels lifted.
If towing is necessary, we recommend having your vehicle towed by
your Toyota dealer or a commerci al towing service, using a lift-type
truck or flat bed truck.
Use a safety chain system for all to wing, and abide by all state/pro-
vincial and local laws.

5
When trouble arises
521
5-2. Steps to take in an emergency
Interior
buzzerExterior buzzerWarning messageDetailsCorrection procedure
Contin-
uous Contin-
uous
(Displayed alternately)(Flashes) An open door
other than the
driver’s door is
closed while the
electronic key is
outside the
detection range
and the
“POWER”
switch is in
ACCESSORY
or ON mode
with the shift
position not in P.
• Shift the
shift posi-
tion to P.
• Confirm the loca-
tion of the
electronic
key.
Once 
(Comes on for 15 seconds.)
The electronic
key battery is
low. Replace
the bat-
tery.
(
P. 454)
Once 
(Flashes)An open door
has been
closed and the
“POWER”
switch has been
turned twice to
the ACCES-
SORY mode
from OFF. Press the
“POWER”
switch
while
applying
the
brakes.

522 5-2. Steps to take in an emergency
InteriorbuzzerExterior buzzerWarning messageDetailsCorrection procedure
Once 
(Flashes)The elec-
tronic key
does not
operate
properly.
P. 541
 Power
was
turned off
due to
the auto-
matic
power off
function.Next time when
starting the
hybrid system,
increase the
engine speed
slightly and
maintain that
level for approxi-
mately 5 min-
utes to recharge
the battery.
NOTICE
■
While the engine oil level warning is displayed
Continued engine operation with low engine oil will damage the engine.
■ Engine oil maintenance message
The warning message is based on the projected driving range after engine
oil maintenance message is reset.
The system does not monitor the purity of the engine oil.

538
5-2. Steps to take in an emergency
If the hybrid system will not start
Reasons for the hybrid system not starting vary depending on the
situation. Check the following a nd perform the appropriate proce-
dure:
■ The hybrid system will not start even though the correct
starting procedure is being followed ( P. 192)
One of the following may be the cause of the problem:
● The electronic key may not be functioning properly.
*
(  P. 541)
● There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
● There may be a malfunction in the immobilizer system.
*
(  P. 135)
● There may be a malfunction in the P position control system.
*
( P. 197, 509)
*: It may not be possible to shift the shift position from P to another
position.
■ The interior lights and headlights are dim, or the horn does
not sound or sounds at a low volume
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( P. 543)
● The 12-volt battery terminal c onnections may be loose or cor-
roded.