Page 392 of 552
3927-3. Do-it-yourself maintenance
PRIUS c_U (OM52E68U)
Disconnect the claws and
remove the service cover.
Remove the reservoir cap.
Add brake fluid slowly while checking the fluid level.
■Brake fluid can absorb moisture from the air
Excess moisture in the brake fluid can cause a dangerous loss of braking effi-
ciency. Use only newly opened brake fluid.
2
3
WARNING
■When filling the reservoir
Take care as brake fluid can harm your hands and eyes and damage
painted surfaces.
If fluid gets on your hands or in your eyes, flush the affected area with clean
water immediately.
If you still experience discomfort, see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads
wear out or when the fluid level in the accumulator is high.
If the reservoir needs frequent refilling, there may be a serious problem.
4
Page 441 of 552

4418-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U (OM52E68U)
If a war ning light tur ns on or a war ning
buzzer sounds
Calmly perform the following actions if any of the warning lights
comes on or flashes. If a light comes on or flashes, but then
goes off, this does not necessarily indicate a malfunction in the
system. However, if this continues to occur, have the vehicle
inspected by your Toyota dealer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
Brake system warning light in red (warning buzzer)*1
• Low brake fluid
• Malfunction in the brake system This light also comes on when the parking brake is not
released. If the light turns off after the parking brake is
fully released the system is operating normally.
Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer. Continuing to drive the vehi-
cle may be dangerous.
Brake system warning light in yellow
Indicates a malfunction in:
• The regenerative brake system; or
• The electronically controlled brake system
Have the vehicle inspected by your Toyota dealer
immediately.
Page 442 of 552

4428-2. Steps to take in an emergency
PRIUS c_U (OM52E68U)
Warning lightWarning light/Details/Actions
Charging system warning lightIndicates a malfunction in the vehicle's charging system
Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer.
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The hybrid system;
• The electronic engine control system; or
• The electronic throttle control system
Have the vehicle inspected by your Toyota dealer
immediately.
SRS warning light
Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system
Have the vehicle inspected by your Toyota dealer
immediately.
(U.S.A.)
(Canada)
ABS warning light Indicates a malfunction in:
• The ABS; or
• The brake assist system
Have the vehicle inspected by your Toyota dealer
immediately.
Electric power steering system warning light (warning
buzzer)
Indicates a malfunction in the EPS (Electric Power Steer-
ing) system
Have the vehicle inspected by your Toyota dealer
immediately.
Slip indicator light
Indicates a malfunction in:
• The VSC (Vehicle Stability Control) system;
• The TRAC (Traction Control) system; or
• The hill-start assist control system
The light will flash when the VSC, the TRAC or the ABS
system is operating.
Have the vehicle inspected by your Toyota dealer
immediately.
Page 444 of 552

4448-2. Steps to take in an emergency
PRIUS c_U (OM52E68U)
*1: Brake system warning buzzer: When there is a possible problem that could affect braking performance,
the warning light will come on and a warning buzzer will sound.
Parking brake engaged warning buzzer:
P. 452
*2: Driver's and front passenger's seat belt buzzer: The driver's and front passenger's seat belt buzzer sounds to alert the
driver and front passenger that his or her seat belt is not fastened. Once
the engine switch is turned to the “ON” or “START” position (vehicles with-
out a smart key system) or the “POWER” switch is turned to ON mode
(vehicles with a smart key system), 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 30 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.
Tire pressure warning light When the light comes on:
Low tire inflation pressure such as
• Natural causes ( P. 445)
• Flat tire ( P. 462)
Adjust the tire inflation pressure to the specified
level.
The light will turn off after a few minutes. In case
the light does not turn off even if the tire inflation
pressure is adjusted, have the system checked by
your Toyota dealer.
When the light comes on after blinking for 1 minute:
Malfunction in the tire pressure warning system
( P. 446)
Have the system checked by your Toyota dealer.
Warning lightWarning light/Details/Actions
Page 446 of 552

4468-2. Steps to take in an emergency
PRIUS c_U (OM52E68U)■
If the tire pressure warning system is not functioning
P. 402
■
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 configured at Toyota dealer
The vehicle speed linked seat belt reminder buzzer can be disabled. (Cus-
tomizable features P. 514) However, Toyota recommends that the seat belt
reminder buzzer be operational to aler t 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.
If the steering wheel becomes heavier than usual when operating, hold
firmly and operate 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 comes 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 454 of 552

4548-2. Steps to take in an emergency
PRIUS c_U (OM52E68U)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.
Indicates 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 that the TRAC (Traction Control) sys-
tem has been deactivated
Turn the TRAC on. ( P. 233)
Indicates that the accelerator and brake pedals
are being depressed simultaneously, and the
Brake Override System is operating. ( P. 167)
Release the accelerator or brake pedal.
Warning messageDetails/Actions
(Flashes)
(Flashes 3
times)
(Flashes)
Page 459 of 552
4598-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U (OM52E68U)
Once
• The electronic key could notbe detected when the
“POWER” switch was
pressed after the doors were
unlocked with the mechanical
key.
• The electronic key could not be detected two consecutive
times when the “POWER”
switch was pressed.
Touch the electronic key to
the “POWER” switch while
depressing the brake
pedal.
Once
An attempt was made to start
the hybrid system with the shift
lever in a position other than P.
Shift the shift lever to P
and start the hybrid sys-
tem.
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. 413)
Interior
buzzerExterior buzzerWarning messageDetails/Actions
(Flashes)
(Flashes)
Page 539 of 552
539What to do if... (Troubleshooting)
PRIUS c_U (OM52E68U)
●The auto power off function will be operated if the vehicle is left in ACCES-
SORY or ON mode (the hybrid system is not running) for a period of time.
(P. 188)
●The seat belt reminder light is flashing
Are the driver and the front passenger wearing the seat belts? ( P. 443)
●The brake system warning light is on
Is the parking brake released? (P. 200)
Depending on the situation, other types of warning buzzer may also sound.
( P. 441, 449)
●Is the electronic key left inside the vehicle?
Vehicles with a multi-information display: Check the message on the multi-
information display. ( P. 449)
The “POWER” switch is turned off automatically
(vehicles with a smart key system)
A warning buzzer sounds during driving
A warning buzzer sounds when leaving the vehicle
(vehicles with a smart key system)