heating TOYOTA PRIUS PRIME 2021 Owners Manual (in English)

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PRIUS PRIME_OM_OM47D71U_(U)
2-1. Plug-in hybrid system
2
Plug-in hybrid system
Plug-in hybrid vehicle driving tips
◆Using EV mode and HV mode effectively
Primarily using EV mode when driving in cities and using HV mode
when driving on highways (or freeways) can help conserve fuel and
electricity. (P. 9 0 )
◆Using Eco drive mode
When using Eco drive mode, the torque corresponding to the accel-
erator pedal depression amount can be generated more smoothly
than it is in normal conditions. In addition, the operation of the air
conditioning system (heating/cooling) will be minimized, improving
fuel and electricity economy. (P. 430)
◆Use of Hybrid System Indicator
Eco-friendly driving is possible by keeping the Hybrid System Indi-
cator within Eco area. (P. 225)
◆Shift position operation
Shift the shift position to D when stopped at a traffic light, or driving
in heavy traffic etc. Shift the shift position to P when parking. When
using the N, there is no positive effect on fuel consumption. In the
N, the gasoline engine operates but electricity cannot be gener-
ated. Also, when using the air conditioning system, etc., the hybrid
battery (traction battery) power is consumed.
For economical and ecological driving, pay attention to the fol-
lowing points:

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PRIUS PRIME_OM_OM47D71U_(U)
2-2. Charging
For safety, inspect the charging cable on a routine basis.
Inspecting and maintaining the charging cable
WARNING
■Routine inspection
Check the following points regularly.
Failure to do so may cause an unexpected accident, resulting in death or
serious injury.
●The charging cable, plug, charging connector, CCID (Charging Circuit
Interrupting Device) etc. have not been damaged
●The outlet has not been damaged
●The plug can be securely inserted into the outlet
●The plug does not get extremely hot during use
●The tip of the plug has not been deformed
●The plug is not dirtied by dust etc.
Remove the plug from the outlet before inspecting it. If any abnormalities
are found in the charging cable as a result of the inspection, immediately
stop use and consult your Toyota dealer.
■Maintaining the charging cable
When the charging cable is dirty, first remove the dirt with a hard, wringed
cloth, and then wipe the cable with a dry cloth.
However, never wash it with water. If the charging cable is washed with
water, fire or electric shock may occur during charging, possibly resulting in
death or serious injury.
■When not using the charging cable for a long time
Remove the plug from the outlet. Dust could accumulate on the plug or in
the outlet, possibly causing overheating which could lead to a fire.
Also, keep the cable in a place free from moisture.

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PRIUS PRIME_OM_OM47D71U_(U)
3. Instrument cluster
■BSM (Blind Spot Monitor) outside rear view mirror indicators
(if equipped) (P. 432)
• When the BSM function is enabled on the screen of the multi-infor-
mation display, the power switch is turned to ON mode.
If the system is functioning correctly, the BSM outside rear view mirror indi-
cators will turn off after a few seconds.
If the BSM outside rear view mirror indicators do not illuminate or do not
turn off, there may be a malfunction in the system.
If this occurs, have the vehicle inspected by your Toyota dealer. ●Indicators are also displayed on the out-
side rear view mirrors.
●In order to confirm operation, the BSM
outside rear view mirror indicators illumi-
nate in the following situations:
• When the power switch is in ON
mode, the BSM function is enabled
on the screen of the multi-infor-
mation display.
WARNING
■If a safety system warning light does not come on
Should a safety system light such as the ABS and SRS warning light not
come on when you start the hybrid system, this could mean that these sys-
tems are not available to help protect you in an accident, which could result
in death or serious injury. Have the vehicle inspected by your Toyota dealer
immediately if this occurs.
NOTICE
■To prevent damage to the engine and its components
The engine may be overheating if the high coolant temperature warning
light comes on or flashes. In this case, immediately stop the vehicle in a
safe place, and check the engine after it has cooled completely. (P. 721)

PRIUS PRIME_OM_OM47D71U_(U)
3295-1. Before driving
5
Driving
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When taking a nap in the vehicle
Always turn the hybrid system off. Otherwise, if you accidentally move the
shift lever or depress the accelerator pedal, this could cause an accident or
fire due to hybrid system overheating. Additionally, if the vehicle is parked in
a poorly ventilated area, exhaust gases may collect and enter the vehicle,
leading to death or a serious health hazard.
■When braking
●When the brakes are wet, drive more cautiously.
Braking distance increases when the brakes are wet, and this may cause
one side of the vehicle to brake differently than the other side. Also, the
parking brake may not securely hold the vehicle.
●If the electronically controlled assist function does not operate, do not fol-
low other vehicles closely and avoid downhill or sharp turns that require
braking.
In this case, braking is still possible, but the brake pedal should be
depressed more firmly than usual. Also, the braking distance will increase.
Have your brakes fixed immediately.
●The brake system consists of 2 or more individual hydraulic systems; if
one of the systems fails, the other(s) will still operate. In this case, the
brake pedal should be depressed more firmly than usual and the braking
distance will increase. Have your brakes fixed immediately.

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PRIUS PRIME_OM_OM47D71U_(U)
5-2. Driving procedures
Parking brake
To set the parking brake, fully
depress the parking brake pedal
with your left foot while depress-
ing the brake pedal with your right
foot.
(Depressing the pedal again
releases the parking brake.)
■Parking the vehicle
P. 321
■Parking brake engaged warning buzzer
A buzzer will sound if the vehicle is driven with the parking brake engaged.
“Release Parking Brake” is displayed on the multi-information display (with
the vehicle reached a speed of 3 mph [5 km/h]).
■Usage in winter time
P. 508
Operating instructions
(U.S.A.)
(Canada)
NOTICE
■Before driving
Fully release the parking brake.
Driving the vehicle with the parking brake set will lead to brake components
overheating, which may affect braking performance and increase brake
wear.

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PRIUS PRIME_OM_OM47D71U_(U)
5-5. Using the driving support systems
■ECB operating sound
ECB operating sound may be heard in the following cases, but it does not
indicate that a malfunction has occurred.
●Operating sound heard from the engine compartment when the brake pedal
is operated.
●Motor sound of the brake system heard from the front part of the vehicle
when the driver’s door is opened.
●Operating sound heard from the engine compartment when one or two min-
utes passed after the stop of the hybrid system.
■EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■Automatic reactivation of TRAC and VSC systems
After turning the TRAC and VSC systems off, the systems will be automati-
cally re-enabled in the following situations:
●When the power switch is turned off
●If only the TRAC system is turned off, the TRAC will turn on when vehicle
speed increases
If both the TRAC and VSC systems are turned off, automatic re-enabling
will not occur when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from
overheating when there is frequent steering input over an extended period of
time. The steering wheel may feel heavy as a result. Should this occur, refrain
from excessive steering input or stop the vehicle and turn the hybrid system
off. The EPS system should return to normal within 10 minutes.
■Electric power steering system warning light (warning buzzer)
P. 675

5186-1. Using the air conditioning system and defogger
PRIUS PRIME_OM_OM47D71U_(U)
■Heating
●In HV mode, the gasoline engine may operate in order to extract heat from
the engine coolant via the heater.
●In EV mode, heating is done by a heat pump system.
• When the outside temperature is low or it is snowing, compared to con-
ventional vehicles, heating may be less effective and warm air may not
come out.
• If frost has formed on the outside heat exchanger, the heating perfor-
mance will decline. The frost can be removed from the outside heat
exchanger by operating the Remote Air Conditioning System before driv-
ing (P. 535). When frosted over, the heating operation of the Remote
Air Conditioning System starts after defrosting.
• When is turned on, the heating is controlled optimally. Therefore,
the set heating performance may not be achieved even if the fan speed
setting is increased.
●In the following situations the gasoline engine may operate in order to
extract heat from the engine coolant via the heater even in EV mode.
• The outside temperature is approximately 14°F (-10°C) or low
• is operating
■Using automatic mode
Fan speed is adjusted automatically according to the temperature setting and
the ambient conditions.
Therefore, the fan may stop for a while until warm or cool air is ready to flow
immediately after is pressed.
■Water droplets during air conditioning operation• When the outside heat exchanger is
frosted over, fan speed declines and it
may become harder to heat the inte-
rior. However, it is not a malfunction.
In this situation, the air temperature
from the outlets may not change even
though the set temperature is raised.
The outside heat exchanger, accumulator
and air conditioning piping may incur con-
densation or frost may form. During or
after the air conditioning operation, water
droplets may fall from the vehicle. How-
ever, it is not a malfunction.
Outside heat exchanger
Outside heat exchanger
Accumulator

5206-1. Using the air conditioning system and defogger
PRIUS PRIME_OM_OM47D71U_(U)■Fogging up of the windows
●The windows will easily fog up when the humidity in the vehicle is high.
Turning on will dehumidify the air from the outlets and defog the
windshield effectively.
●If you turn off, the windows may fog up more easily.
●The windows may fog up if the recirculated air mode is used.
■Windshield fog detection function
When automatic mode is set, the humidity sensor (P. 523) detects fog on
the windshield and controls the air conditioning system to prevent fog.
■When driving on dusty roads
Close all windows. If dust thrown up by the vehicle is still drawn into the vehi-
cle after closing the windows, it is recommended that the air intake mode be
set to outside air mode and the fan speed to any setting except off.
■Outside/recirculated air mode
●Setting to the recirculated air mode temporarily is recommended in prevent-
ing dirty air from entering the vehicle interior and helping to cool the vehicle
when the outside air temperature is high.
●Outside/recirculated air mode may automatically switch depending on the
temperature setting or the inside temperature.
■Fresh air intake system while parking
When parking, the system automatically switches to outside air mode to
encourage better air circulation throughout the vehicle, helping to reduce
odors that occur when starting the vehicle.
■Operation of the air conditioning system in the air conditioning eco
mode
●In the air conditioning eco mode, the air conditioning system is controlled as
follows to prioritize fuel efficiency:
• Engine speed and compressor operation controlled to restrict heating/
cooling capacity
• Fan speed restricted when automatic mode is selected
●To improve air conditioning performance, perform the following operations:
• Adjust the fan speed
• Adjust the temperature setting
• Turn off the air conditioning eco mode
●When the driving mode is set to Eco driving mode, the air conditioning eco
mode will be turned on automatically. Even in this case, the air conditioning
eco mode can be turned off by pressing . (P. 430)
■When the outside temperature falls to nearly 32F (0C)
The dehumidification function may not operate even when is pressed.

PRIUS PRIME_OM_OM47D71U_(U)
5236-1. Using the air conditioning system and defogger
6
Interior features
NOTICE
■Humidity sensor
●Do not spray the glass cleaner on the sensor or subject it to strong impacts
●Do not stick anything on the sensor
■To prevent 12-volt battery discharge
Do not leave the air conditioning system on longer than necessary when the
hybrid system is off.
■When repairing/replacing parts of the air conditioning system
Have repair/replacement performed by your Toyota dealer. When a part of
the air conditioning system, such as the evaporator, is to be replaced, it
must be replaced with a new one.
■Air outlets
The air outlets become hot when used for heating. Therefore, use caution
and adjust the air outlets accordingly.
In order to detect fog on the windshield, a
sensor which monitors the temperature
of the windshield, the surround humidity,
etc. is installed. (P. 520)
Follow these points to avoid damaging
the sensor:
●Do not disassemble the sensor

PRIUS PRIME_OM_OM47D71U_(U)
5296-1. Using the air conditioning system and defogger
6
Interior features
■Heating
●In HV mode, the gasoline engine may operate in order to extract heat from
the engine coolant via the heater.
●In EV mode, heating is done by a heat pump system.
• When the outside temperature is low or it is snowing, compared to con-
ventional vehicles, heating may be less effective and warm air may not
come out.
• If frost has formed of the outside heat exchanger, the heating perfor-
mance will decline. The frost can be removed from the outside heat
exchanger by operating the Remote Air Conditioning System before driv-
ing (P. 535). When frosted over, the heating operation of the Remote
Air Conditioning System starts after defrosting.
• When is turned on, the heating is controlled optimally. There-
fore, the set heating performance may not be achieved even if the fan
speed setting is increased.
●In the following situations the gasoline engine may operate in order to
extract heat from the engine coolant via the heater even in EV mode.
• The outside temperature is approximately 14°F (-10°C) or low
• is operating
■Using automatic mode
Fan speed is adjusted automatically according to the temperature setting and
the ambient conditions.
Therefore, the fan may stop for a while until warm or cool air is ready to flow
immediately after is pressed.
■Water droplets during air conditioning operation• When the outside heat exchanger is
frosted over, fan speed declines and it
may become harder to heat the inte-
rior. However, it is not a malfunction.
In this situation, the air temperature
from the outlets may not change even
though the set temperature is raised.
The outside heat exchanger, accumulator
and air conditioning piping may incur con-
densation or frost may form. During or
after the air conditioning operation, water
droplets may fall from the vehicle. How-
ever, it is not a malfunction.
Outside heat exchanger
Outside heat exchanger
Accumulator