Page 634 of 784
634
PRIUS PRIME_OM_OM47A88U_(U)
7-3. Do-it-yourself maintenance
Using a Phillips-head screw-
driver, turn bolt A in either direc-
tion.
Remember the turning direction
and the number of turns.
Turn bolt B the same number of
turns and in the same direction
as step .
If the headlight cannot be adjusted
using this procedure, take the vehi-
cle to your Toyota dealer to adjust
the headlight aim.
Adjusting the headlight aim
1
2
1
Page 640 of 784

640
PRIUS PRIME_OM_OM47A88U_(U)
7-3. Do-it-yourself maintenance
■Replacing the following bulbs
If any of the lights listed below has burnt out, have it replaced by
your Toyota dealer.
● Headlights and daytime running lights
● Front side marker lights
● Parking lights
● Fog lights (if equipped)
● LED accent lights (if equipped)
● Front turn signal lights
● Rear turn signal lights
● Rear side marker lights
● Tail lights
● Stop lights
● High mounted stoplight
● License plate lights
■LED lights
The lights other than the back-up lights each consist of a number of LEDs. If
any of the LEDs burn out, take your vehicle to your Toyota dealer to have the
light replaced.
■ Condensation build-up on the inside of the lens
Temporary condensation build-up on the inside of the headlight lens does not
indicate a malfunction. Contact your Toyota dealer for more information in the
following situations:
●Large drops of water have built up on the inside of the lens.
● Water has built up inside the headlight.
■ When replacing light bulbs
→P. 632
Page 641 of 784

PRIUS PRIME_OM_OM47A88U_(U)
6417-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■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. When it is
unavoidable to hold the glass portion, use and hold with a clean dry cloth
to avoid getting moisture and oils on the bulb.
Also, 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.
● Do not attempt to repair or disassemble light bulbs, connectors, electric
circuits or component parts.
Doing so may result in death or serious injury due to electric shock.
● Do not replace the right-hand back-up light immediately after the vehicle
has been driven.
After the vehicle has been driven the exhaust pipe will be extremely hot,
and touching the exhaust pipe may result in burns.
● Use gloves and other protection to prevent injuries on vehicle parts.
There is the danger of being injured on the edges of parts.
■ To prevent damage or fire
● Make sure bulbs are fully seated and locked.
● Check the wattage of the bulb before installing to prevent heat damage.
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PRIUS PRIME_OM_OM47A88U_(U)
8-2. Steps to take in an emergency
If the hybrid system will not start
One of the following may be the cause of the problem:
●The charging cable may be attached to the vehicle. ( →P. 136)
● The electronic key may not be functioning properly.
* (→ P. 690)
● There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle. ( →P. 92)
● There may be a malfunction in the immobilizer system.
* (→ P. 7 5 )
● There may be a malfunction in the shift control system.
*
( → P. 327, 669)
● The hybrid system may be malfunctioning due to an electrical prob-
lem such as electronic key battery depletion or a blown fuse. How-
ever, depending on the type of malfunction, an interim measure is
available to start the hybrid system. (→ P. 689)
● There is a possibility that the temperature of the hybrid battery
(traction battery) is extremely low (approximately below -22°F
[-30°C]). ( →P. 92, 326)
*: It may not be possible to shift the shift position other than P.
One of the following may be the cause of the problem:
● The 12-volt battery may be discharged. ( →P. 694)
● The 12-volt battery terminal con nections may be loose or corroded.
( → P. 587)
Reasons for the hybrid system not starting vary depending on
the situation. Check the follo wing and perform the appropriate
procedure:
The hybrid system will not start even though the correct starting
procedure is being followed. ( →P. 324)
The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume.
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6898-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47A88U_(U)
8
When trouble arises
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( →P. 694)
● One or both of the 12-volt batter y terminals may be disconnected.
( → P. 587)
Contact your Toyota dealer if the problem cannot be repaired, or if repair
procedures are unknown.
When the hybrid system does not start, the following steps can be
used as an interim measure to star t the hybrid system if the power
switch is functioning normally.
Do not use this starting procedure except in cases of emergency.
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 headlight s do not turn on, or the horn
does not sound.
Emergency start function
1
2
3
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6968-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47A88U_(U)
Once the hybrid system has started, remove the jumper cables in
the exact reverse order from which they were connected.
To install the engine cover, conduct the removal procedure in
reverse. After installing, check that the fixed pins are inserted
securely.
Once the hybrid system starts, ha ve the vehicle inspected at your
Toyota dealer as soon as possible.
■ When opening the cover of th e positive (+) battery terminal
→P. 587
■ 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 running
at a low speed for an extended period, such as in heavy traffic.
■ When the 12-volt battery is removed or discharged
●Information stored in the ECU is cleared. When the 12-volt battery is
depleted, have the vehicle inspected at your Toyota dealer.
● Some systems may require initialization. ( →P. 743)
■ When removing the 12-volt battery terminals
When the 12-volt battery terminals are removed, the information stored in the
ECU is cleared. Before removing the 12-volt battery terminals, contact your
Toyota dealer.
■ 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 operating.)
7
8
Page 738 of 784
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PRIUS PRIME_OM_OM47A88U_(U)
9-2. Customization
■Automatic light control system*1 (→ P. 338)
*1: If equipped
*2: This function cannot be customized for vehicles sold in Canada.
■
Rain-sensing windshield wipers* ( → P. 352)
*: If equipped
■
Intuitive parking assist* ( → P. 420)
*: If equipped
FunctionDefault
settingCustomized setting
Time elapsed before the
headlights turn off 30 secondsOff
–OO
60 seconds
90 seconds
Light sensor sensitivityLevel 0Level -2 to 2–OO
Daytime running lights*2OnOff–OO
123
FunctionDefault
settingCustomized setting
Wiper operation when the
wiper switch is in the “AUTO”
positionRain-sensing operation
Intermittent operation
linked to vehi- cle speed
(with interval
adjuster)
––O
123
FunctionDefault settingCustomized setting
Detection distance of the front
center sensorsFarNear––O
Detection distance of the rear
center sensorsFarNear––O
Buzzer volume31 to 5––O
123
Page 745 of 784
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PRIUS PRIME_OM_OM47A88U_(U)
10For owners
Reporting safety defects for U.S. owners........................ 746
Seat belt instructions for Canadian owners
(in French) ............................... 747
SRS airbag instructions for Canadian owners
(in French) ............................... 749
Headlight aim instructions for Canadian owners
(in French) ............................... 758