
562
PRIUS_OM_OM47E09U_(U)
6-3. Do-it-yourself maintenance
WARNING
■Battery precautions
Observe the following precautions. 
Failure to do so may result in death or serious injury.
● Do not swallow the battery. Doing so may cause chemical burns.
● A coin battery or button battery is used in the electronic key. If a battery is
swallowed, it may cause severe chemical burns in as little as 2  hours and
may result in death or serious injury.
● Keep away new and removed batteries from children.
● If the cover cannot be firmly closed, stop using the electronic  key and stow
the  key  in  the  place  where  children  cannot  reach,  and  then  contact  your
Toyota dealer.
● If  you  accidentally  swallow  a  battery  or  put  a  battery  into  a  p art  of  your
body, get emergency medical attention immediately.
■ To prevent battery explosion or  leakage of flammable liquid or gas
● Replace the battery with a new battery of the same type. If a w rong type of
battery is used, it may explode.
● Do  not  expose  batteries  to  extremely  low  pressure  due  to  high  altitude  or
extremely high temperatures.
● Do not burn, break or cut a battery.
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 cont rol.
● Do not bend either of the battery terminals. 

579
PRIUS_OM_OM47E09U_(U)
7When trouble arises
7-1. Essential informationEmergency flashers .......... 580
If your vehicle has to be stopped in an 
emergency ...................... 581
If the vehicle is trapped in  rising water ..................... 582
7-2. Steps to take in an  emergency
If your vehicle needs to  be towed ......................... 584
If you think something is  wrong .............................. 591
If a warning light turns on  or a warning buzzer 
sounds ............................ 592
If a warning message is  displayed......................... 603
If you have a flat tire  (vehicles without 
spare tire)........................ 611
If you have a flat tire  (vehicles with 
spare tire)........................ 631
If the hybrid system will  not start ........................... 645
If the electronic key does  not operate properly ........ 647
If the 12-volt battery is  discharged ...................... 650
If your vehicle overheats ... 656
If the vehicle becomes  stuck ............................... 661 

580
PRIUS_OM_OM47E09U_(U)
7-1. Essential information
Emergency flashers
Press the switch.
All  the  turn  signal  lights  will  flash. To  turn  them  off,  press  the  switch  once
again.
■ Emergency flashers
●If the emergency flashers are used for a long time while the hy brid system is
not  operating  (while  the  “READY”  indicator  is  not  illuminated),   the  12-volt
battery may discharge.
● If  any  of  the  SRS  airbags  deploy  (inflate)  or  in  the  event  of  a  strong  rear
impact, the emergency flashers will turn on automatically. 
The emergency flashers will turn off automatically after operating for approx-
imately  20  minutes. To  manually turn  the  emergency  flashers  off, press  the
switch twice. 
(The  emergency  flashers  may  not  turn  on  automatically  depending   on  the
force of the impact and conditions of the collision.)
The emergency flashers are used to warn other drivers when the
vehicle has to be stopped in the road due to a breakdown, etc.
Vehicles with 7-inch displayVehicles with 11.6-inch display 

584
PRIUS_OM_OM47E09U_(U)
7-2. Steps to take in an emergency
If  your vehicle needs to be towed
In  the  following  situations,  it is  not  possible  to  be  towed  by  another
vehicle using cables or chains, as the front wheels may be lock ed due
to the parking lock. Contact your  Toyota dealer or commercial towing
service.
● There is a malfunction in t he shift control system. (P. 249, 609)
● There is a malfunction in the immobilizer system. ( P. 95)
● There is a malfunction in  the smart key system. (P. 647)
● The 12-volt battery is discharged. ( P.   6 5 0 )
The  following  may  indicate  a  problem  with  your  hybrid  transmiss ion.
Contact your Toyota dealer or commercial towing service before  tow-
ing.
● The  hybrid  system  warning  message  is  displayed  and  the  vehicle
does not move.
● The vehicle makes an abnormal sound.
If  towing  is  necessary,  we  recommend  having  your  vehicle
towed  by  your  Toyota  dealer  o r  commercial  towing  service,
using a wheel-lift type t ruck or flatbed truck.
Use  a  safety  chain  system  for  all  towing,  and  abide  by  all  stat e/
provincial and local laws.
Situations when it is not possibl e to be towed by another vehicle
Situations when it is necessary to contact dealers before towing 

5987-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)
■SRS warning light
This  warning  light  system monitors  the  airbag  sensor  assembly,  front  impact
sensors,  side  impact  sensors  (front  door),  side  impact  sensors  (front),  side
impact sensors (rear), driver’s seat belt buckle switch, front  passenger occu-
pant classification system (ECU and sensors), “AIR BAG ON” indi cator light,
“AIR BAG OFF” indicator light, front passenger’s seat belt buck le switch, seat
belt pretensioners, airbags, interconnecting wiring and power s ources. 
( P. 35)
■ Front  passenger  detection  sensor,  seat  belt  reminder  and  warnin g
buzzer
● If luggage is placed on the front passenger seat, the front pas senger detec-
tion sensor may cause  the warning light to  flash and the warnin g  buzzer  to
sound even if a passenger is not sitting in the seat.
● If  a  cushion  is  placed  on  the  seat,  the  sensor  may  not  detect  a  passenger,
and the warning light may not operate properly.
■ Electric power steering system wa rning light (warning buzzer)
When  the  12-volt  battery  charge  becomes  insufficient  or  the  vol tage  tempo-
rarily  drops,  the  electric  power   steering  system  warning  light  may  come  on
and the warning buzzer may sound.
■ If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
● Is the fuel tank cap loose?
If it is, tighten it securely.
The malfunction indicator lamp will go off after several drivin g trips.
If the malfunction indicator lamp does not go off even after several trips, con-
tact your Toyota dealer as soon as possible. 

6067-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)■
If “See Owner’s Manual” is shown
●If “Braking Power Low Stop in a Safe Place See Owner’s Manual”  is shown,
this may be a malfunction. Immediately stop the vehicle in a sa fe place and
contact  your Toyota  dealer.  Continuing  to  drive  the  vehicle  may  be  danger-
ous.
● If  “Engine  Oil  Pressure  Low”  is  shown,  this  may  be  a  malfunction.  Immedi-
ately stop the vehicle in a safe place and contact your Toyota  dealer.
● If  the  following  messages are  shown,  there  may  be  a  malfunction .  Immedi-
ately have the vehicle inspected by your Toyota dealer.
• “Hybrid System Malfunction”
• “Check Engine”
• “Hybrid Battery System Malfunction”
• “Accelerator System Malfunction”
• “Smart Key System Malfunction See Owner’s Manual”
■ If “Shift System Not A ctive Apply Parking Brake Securely While  Parking
See Owner’s Manual” is shown
Indicates a temporary operation failure or malfunction in the shift control sys-
tem. Immediately have the vehicle inspected by your Toyota deal er.
When  the  message  is  shown,  the  hybrid  system  may  not  be  started or the
shift position may not be changed normally. (Coping method:  P. 609)
■ If  “Shift  System  Malfunction A pply  Parking  Brake  Securely  While   Park-
ing See Owner’s Manual” is shown
Indicates a malfunction in the shift control system. Immediatel y have the vehi-
cle inspected by your Toyota dealer.
When  the  message  is  shown,  the  hybrid  system  may  not  be  started  or the
shift position may not be changed normally. (Coping method:  P. 609)
■ If  “   Switch  Malfunction Apply  Par king  Brake  Securely  While  Parking
See Owner’s Manual” is shown
The  P  position  switch  may  not  operate.  Immediately  have  the  veh icle
inspected by your Toyota dealer. 
When  parking  the  vehicle,  stop  the  vehicle  on  level  ground  and  apply  the
parking brake firmly.
■ If  “Shift  System  Malfunction  Shi fting  Unavailable  See  Owner’s  M anual”
is shown
Indicates a malfunction in the shift control system. Immediatel y have the vehi-
cle inspected by your Toyota dealer. 
The shift position may not be shifted from P to other than P.
■ If  “Shift  System  Malfunction  S top  in  a  Safe  Place  See  Owner’s  Manual”
is shown
Indicates a malfunction in the shift control system. Immediatel y have the vehi-
cle inspected by your Toyota dealer. 
The shift position may not be changed. Stop the vehicle in a sa fe place. 

6077-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)
7
When trouble arises
■If “Shift System Malfunction  See Owner’s Manual” is shown
Indicates a malfunction in the shift control system. Immediatel y have the sys-
tem inspected by your Toyota dealer.
The system may not operate properly.
■ If “Low 12-Volt Battery Apply Parking Brake Securely While Park ing See
Owner’s Manual” is shown
Indicates that the 12-volt battery charge is insufficient. Char ge or replace the
12-volt battery.
● When  the  message  is  shown,  the  hybrid  system  may  not  start  or  t he  shift
position may not be changed normally. (Coping method:  P. 609)
● After charging the 12-volt battery, the message may not go off  until the shift
position is changed from P.
■ If  “Shifting  Unavailable  Low  12-Volt  Battery  See  Owner’s  Manual ”  is
shown
Indicates that the shift position cannot be changed because the  voltage of the
12-volt battery drops. Charge or replace the 12-volt battery.
(Coping method in the case the 12-volt battery is discharged:  P. 650)
■ If “Hybrid System Overheated.  Reduced Output Power.” is shown
The message may be shown when driving under severe operating co nditions.
(For  example,  when  driving  up  a  long  steep  hill  or  driving  up  a   steep  hill  in
reverse.)
Coping method: P. 656
■ If  “Maintenance  required  for  Traction  battery  cooling  parts  See   owner’s
manual” is shown
The filter may be clogged, the air intake vent may be blocked or there may be
a gap in the duct. 
● If  the  air  intake  vent  is  dirty,  refer  to  P.  551  for  information  on  how  to  clean
the air intake vent.
● If the message is shown when the air intake vent is not dirty,  have the vehi-
cle inspected by your Toyota dealer.
■ If  “Traction  Battery  Needs  to  be  Protected  Refrain  From  the  Use of 
Position” is shown
This message may be displayed when the shift position is in N.
As  the  hybrid  battery  (traction  battery)  can  not  be  charged  when  the  shift
position is in N, shift the shift position to P when the vehicle is stopped.
■ If  “Traction  Battery  Needs  to  be  Protected  Shift  into    to  Resta rt”  is
shown
This  message  is  displayed  when  the  hybrid  battery  (traction  battery)  charge
has become extremely low because the vehicle has been left with  the N shift
position selected for a certain amount of time.
When operating the vehicle, shift to P and restart the hybrid s ystem. 

6087-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)■
If “Shift to   Before Exiting Vehicle” is shown
Message  is  displayed  when  the  driver’s  door  is  opened  without  t urning  the
power switch to off with the shift position in any position oth er than P.
Shift the shift position to P.
■ If “Shift is in   Release Accelerat or Before Shifting” is shown
Message  is  displayed  when  the  accelerator  pedal  has  been  depressed  and
the shift position is in N. 
Release the accelerator pedal and shift the shift position to D  or R.
■ If  “Depress  Brake  When  Vehicle  is  Stopped.  Hybrid  System  may  Ov er-
heat.” is shown
The message may be shown when the accelerator pedal is depresse d to hold
the vehicle while the vehicle is stopped on an uphill, etc.
The hybrid system may overheat. Release the accelerator pedal a nd depress
the brake pedal.
■ If “Shifted to   Stop Vehicle to Shift to  ” is shown
If  the  P  position switch is  pressed  while driving,  the shift po sition  is changed
to N and the message is shown. ( P. 257)
■ If “Auto Power OFF to Conserve Battery” is shown
The power switch has been turned off by the automatic power off  function.
When  starting  the  hybrid  system  next  time,  operate  the  hybrid  s ystem  for
approximately 5 minutes to recharge the 12-volt battery.
■ If “Engine Oil Level Low Add or Replace” is displayed
The  engine  oil  level  may  be  low.  Check  the  level  of  the  engine  oil,  and  add
engine  oil  if  necessary.  This  message  may  be  displayed  if  the  vehicle  is
stopped on a slope. Move the vehicle to a level surface and che ck if the mes-
sage disappears.
■ If “Accelerator and Brake Pedals Pressed Simultaneously” is sho wn
The accelerator and brake pedals are being depressed simultaneo usly. 
( P. 229)
Release the accelerator pedal and depress the brake pedal.
■ If  a  message  that  indicates  the  malfunction  of  front  camera  is  dis-
played.
*
The  following  systems  may  be  suspended  until  the  problem  shown  in  the
message is resolved. ( P. 294, 592)
● PCS (Pre-Collision System)
*
●LTA (Lane Tracing Assist)*
●AHB (Automatic High Beam)*
●RSA (Road Sign Assist)*
●Dynamic radar cruise control with full-speed range*
*
: If equipped