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5-1. Essential information
PRIUS v_OM_OM47820U_(U)
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact your Toyota dealer as soon as
possible.
■ Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air cond itioning after use is normal.)
● Flat-looking tires or uneven tire wear
● High engine coolant temperatur e warning light flashes or
comes on
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the hybrid system
■ Operational symptoms
●Engine missing, stumbling or running roughly
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, s pongy feeling, pedal almost
touches the floor
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5-2. Steps to take in an emergency
If a war ning light tur ns on or a war ning buzzer sounds
Stop the vehicle immediately. Continuing to drive the vehicle
may be dangerous.The following warning indicates a possible problem in the brake sys-
tem. Immediately stop the vehicle in a safe place and contact your
Toyota dealer.
*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.
*2: Parking brake engaged warning buzzer:
A buzzer will sound if the vehicle is driven at a speed of approximately 3
mph (5 km/h) or more.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Brake system warning light and warning buzzer (red
indicator)
*1, 2
• 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.
Calmly perform the following actio ns 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 o ccur, have the vehicle inspected by
your Toyota dealer.
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448 5-2. Steps to take in an emergency
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Have the vehicle inspected by your Toyota dealer immediately.Failure to investigate the cause of the following warnings may lead to
the system operating abnormally and possibly cause an accident.
Have the vehicle inspected by your Toyota dealer immediately.
Warning lightWarning light/Details
(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
SRS warning light Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system
(U.S.A.)
(Canada)
ABS warning light Indicates a malfunction in:
• The ABS; or
• The brake assist system
Electric power steering syst em warning light (warn-
ing buzzer) Indicates a malfunction in the EPS system
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5-2. Steps to take in an emergency
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Warning lightWarning light/Details
(Flashes)
(If equipped) Pre-collision syst
em warning light
Indicates a malfunction in the pre-collision system
The warning light will operate as follows, even when the
system is not malfunctioning:
• The light will flash quickly when the system is operating. (P. 258)
• The light will turn on when the pre-collision braking is disabled. ( P. 259)
• The light will turn on when the system cannot tempo- rarily be used. ( P. 452)
(Turns on) Slip indicator light
Indicates a malfunction in:
•VSC;
• TRAC; or
• Hill-start assist control
Flashes when the above systems are operating.
(P. 253)
Brake system warning light (yellow indicator)
Indicates a malfunction in:
• The regenerative braking system; or
• The electronically controlled brake system
Parking lock system warnin
g light (warning buzzer)
Indicates a malfunction in the P position control system
• In this situation, there is a possibility that the parking lock mechanism will not work. When parking, park the
vehicle on a flat surface and apply the parking brake
securely.
• The “POWER” switch may not be turned off. If this hap- pens, applying the parking brake will enable the switch
to be turned off.
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450 5-2. Steps to take in an emergency
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Warning lightWarning light/Details
(U.S.A)
(Canada) Parking lock system warn
ing message (warning
buzzer) Indicates a malfunction in the P position control system
when the vehicle is stopped
• In this situation, there is a possibility that the parking lock mechanism will not work. When parking, park the
vehicle on a flat surface and apply the parking brake
securely.
• The “POWER” switch may not be turned off. If this hap- pens, applying the parking brake will enable the switch
to be turned off.
(If equipped) LED headlight warning light
Indicates a malfunction in the LED headlightsThe LED headlights will not normally illuminate when
there is a malfunction, however it may be able to illumi-
nate depending on the nature of the problem.
(If equipped) Automatic headlight leveling system warning light
Indicates a malfunction in the automatic headlight level-
ing system
(If equipped) (yellow) Cruise control indicator
Indicates a malfunction in the cruise control/dynamic
radar cruise control
(If equipped) (yellow) Radar cruise control indicator
Indicates a malfunction in the dynamic radar cruise con-
trol
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5-2. Steps to take in an emergency
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■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 “POWER” switch
is turned to ON mode, have it
checked by your Toyota dealer.
■ Customization
The vehicle speed linked seat belt reminder buzzer can be disabled.
(Customizable features P. 527) However, Toyota recommends that the
seat belt reminder buzzer be operational to alert the driver and front passen-
ger when seat belts are not fastened.
CAUTION
■ If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact your Toyota
dealer. The vehicle will become extremely unstable during braking, and the
ABS system may fail, which could cause an accident resulting in death or
serious injury.
■ 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.
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458 5-2. Steps to take in an emergency
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CAUTION
■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 pr obable that you have a flat tire. Check the tires.
If a tire is flat, change it with th e 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 syste m may not activate immediately.
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly
when cold and inflated to the inflation pressure recommended by the
vehicle manufacturer on the vehicle placard or tire inflation pressure
label (tire and load information label). (If your vehicle has tires of a differ-
ent size than the size indicated on the vehicle placard or tire inflation
pressure label [tire and load information label], you should determine the
proper tire inflation pr essure for those tires.)
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5-2. Steps to take in an emergency
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Follow the correction procedures.
After taking the specified steps to correct the suspected problem,
check that the warning light turn off.
InteriorbuzzerExterior buzzerWarning lightDetailsCorrection procedure
Once
The electronic key
is not detected
when an attempt
is made to start
the hybrid system.
Start the hybrid sys-
tem with the electronic
key present.
The “POWER”
switch has been
pressed while the
electronic key
was not detected
inside the vehicle.
Confirm the location
of the electronic key.
(P. 60, 66)
If the warning light
does not extinguish
even though the elec-
tronic key is within
operating range,
touch the electronic
key to the “POWER”
switch while depress-
ing the brake pedal
(P. 482)
Transmission
between the elec-
tronic key and the
vehicle is being
blocked, or the bat-
tery in the electronic
key has been
depleted.