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434 4-3. Do-it-yourself maintenance
PRIUS v_U (OM47784U)
CAUTION
■Replacing light bulbs
● Be sure to stop the hybrid system and turn off the lights. Do not attempt to
replace the bulb immediately after turning off the lights.
The bulbs become very hot and may cause burns.
● Do not touch the glass portion of the light bulb with bare hands. Hold the
bulb by the plastic or metal portion.
If the bulb is scratched or dropped, it may blow out or crack.
● Fully install light bulbs and any parts used to secure them. Failure to do so
may result in heat damage, fire, or water entering the headlight unit. This
may damage the headlights or cause condensation to build up on the lens.
■ To prevent damage or fire
Make sure bulbs are fully seated and locked.
Page 436 of 568
436
PRIUS v_U (OM47784U)
5-1. Essential information
Emergency flashers
NOTICE
■To prevent 12-volt battery discharge
Do not leave the emergency flashers on longer than necessary when the
hybrid system is not operating.
Use the emergency flashers if th e vehicle malfunctions or is
involved in an accident.
Press the switch to flash all
the turn signal lights. To turn
them off, press the switch
once again.
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444
PRIUS v_U (OM47784U)
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 systemThis 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
PRIUS v_U (OM47784U)
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
When trouble arises
455
5-2. Steps to take in an emergency
PRIUS v_U (OM47784U)
■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. 525) 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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476
5-2. Steps to take in an emergency
PRIUS v_U (OM47784U)
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. 175)
One of the following may be the cause of the problem:
● The electronic key may not be functioning properly.
*
( P. 479)
● There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
● There may be a malfunction in the immobilizer system.
*
( P. 1 1 9 )
● There may be a malfunction in the P position control system.
*
( P. 180, 447, 448)
*: It may not be possible to shift the shift position from P to another
position.
■ The interior lights and headlight s 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. 481)
● The 12-volt battery terminal c onnections may be loose or cor-
roded.
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5
When trouble arises
477
5-2. Steps to take in an emergency
PRIUS v_U (OM47784U)
Emergency start function
When the hybrid system does not start, the following steps can be
used as an interim measure to st art the hybrid system if the
“POWER” switch is functioning normally:
Set the parking brake.
Turn the “POWER” switch to ACCESSORY mode.
Press and hold the “POWER” switch for about 15 seconds
while depressing the brake pedal firmly.
Even if the hybrid system can be started using the above steps, the
system may be malfunctioning. Have the vehicle inspected by your
Toyota dealer.
■ The interior lights and headlights do not turn on, or the horn
does not sound
One of the following may be the cause of the problem:
●One or both of the 12-volt ba ttery terminals may be discon-
nected.
● The 12-volt battery may be discharged. ( P. 481)
Contact your Toyota dealer if the problem cannot be repaired, or if
repair procedures are unknown.
STEP 1
STEP 2
STEP 3
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484 5-2. Steps to take in an emergency
PRIUS v_U (OM47784U)
■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 run-
ning at a low speed for an extended period, such as in heavy traffic.
■ When the 12-volt battery is removed or discharged
● The hybrid system may not start. ( P. 386)
● If the 12-volt battery is depleted with the shift position in P, it will not be
possible to shift the shift position other than P. In this case, the vehicle
cannot be towed without lifting both front wheels because the front
wheels are locked by the parking lock. ( P. 437)
● When the 12-volt battery is reconnected, start the hybrid system, depress
the brake pedal, and confirm that it is possible to shift into each shift posi-
tion.
■ 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 oper-
ating.)