2023 TOYOTA PRIUS PRIME radiator cap

5047-3. Do-it-yourself maintenance
Engine oil filler cap (P.506)
Engine oil level dipstick ( P.504)
Brake fluid reservoir ( P.509)
Fuse boxes ( P.540)
Washer fluid tank ( P.510)
Radiator ( P.508)
Electric cooling fan
Condenser ( P.508)
Power control unit coolant reservoir ( P.507)
Engine coolant reservoir ( P.507)
■12-volt battery
 P.511
With the engine at operating
temperature and turned off,
check the oil level on the dip-
Engine compartment
Components
A
B
C
D
E
F
G
H
I
J
Checking the engine oil

5087-3. Do-it-yourself maintenance
line. (P.595)
■Coolant selection
Only use “Toyota Super Long Life
Coolant” or a similar high quality
ethylene glycol based non-silicate,
non-amine, non-nitrite, and non-
borate coolant with long-life hybrid
organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is
a mixture of 50% coolant and 50%
deionized water. (Minimum tem-
perature: -31°F [-35°C])
Canada:
“Toyota Super Long Life Coolant” is
a mixture of 55% coolant and 45%
deionized water. (Minimum tem-
perature: -44°F [-42°C])
For more details about coolant, con-
tact your Toyota dealer.
■If the coolant level drops within
a short time of replenishing
Visually check the radiators, hoses,
engine/power control unit coolant
reservoir caps, drain cock and water
pump.
If you cannot find a leak, have your
Toyota dealer, test the cap and
check for leaks in the cooling sys-
tem.
Check the radiator and con-
denser, and clear away any for-
eign objects.
If either of the above parts is
extremely dirty or you are not
sure of their condition, have
your vehicle inspected by your
Toyota dealer.
WARNING
■When the hybrid system is
hot
Do not remove the engine/power
control unit coolant reservoir caps
or the radiator cap.
The cooling system may be under
pressure and may spray hot cool-
ant if the cap is removed, causing
serious injuries, such as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor
straight antifreeze. The correct
mixture of water and antifreeze
must be used to provide proper
lubrication, corrosion protection
and cooling. Be sure to read the
antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to
prevent it from damaging parts or
paint.
Checking the radiator and
condenser
WARNING
■When the hybrid system is
hot
Do not touch the radiator or con-
denser as they may be hot and
cause serious injuries, such as
burns.

5097-3. Do-it-yourself maintenance
7
Maintenance and care
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
■Adding fluid
1 Slide and lift up the rubber
strip to partly remove it, and then remove the clip remove
it as shown in the illustration.
2 Disconnect the claws and
remove the service cover.
3 Remove the reservoir cap.
4 Add brake fluid slowly while
checking the fluid level.
Make sure to check the fluid
type and prepare the necessary
WARNING
■When the electric cooling fan
is operating
Do not touch the engine compart-
ment.
With the power switch in ON, the
electric cooling fan may automati-
cally start to run if the air condi-
tioning is on and/or the coolant
temperature is high. Be sure the
power switch is OFF when work-
ing near the electric cooling fan or
radiator grille.
Checking and adding the
brake fluid

5968-2. Steps to take in an emergency
and “MIN” lines on the reser-
voir.
Reservoir
“MAX” line
“MIN” line
5 Add coolant if necessary.
Water can be used in an emer-
gency if power control unit coolant
is unavailable.
If water was added in an emer-
gency, have the vehicle inspected
at your Toyota dealer as soon as
possible.
6After stopping the hybrid sys-
tem and waiting for 5 minutes
or more, start the hybrid sys-
tem again and check for the
multi-information display.
If the message does not disappear:
Stop the hybrid system and contact
your Toyota dealer.
If the message is not displayed:
The hybrid system temperature has dropped and the vehicle may be
driven normally.
However, if the message appears
again frequently, contact your
Toyota dealer.
A
B
C
WARNING
■When inspecting under the
hood of your vehicle
Observe the following precau-
tions.
Failure to do so may result in seri-
ous injury such as burns.
●If steam is seen coming from
under the hood, do not open the
hood until the steam has sub-
sided. The engine compart-
ment may be very hot.
●After the hybrid system has
been turned off, check that the
“READY” indicator is off.
When the hybrid system is oper-
ating, the gasoline engine may
automatically start, or the cool-
ing fan may suddenly operate
even if the gasoline engine
stops. Do not touch or approach
rotating parts such as the fan,
which may lead to fingers or
clothing (especially a tie, a scarf
or a muffler) getting caught,
resulting in serious injury.
●Do not loosen the coolant reser-
voir cap while th e hybrid system
and radiator are hot.
High temperature steam or
coolant could spray out.
NOTICE
■When adding engine/power
control unit coolant
Add coolant slowly after the
hybrid system has cooled down
sufficiently. Adding cool coolant to
a hot hybrid system too quickly
can cause damage to the hybrid
system.

Alphabetical Index659
Door lock linked window opera-tion ..................................... 228
Jam protection function ........ 227
Operation ............................. 227
Window lock switch .............. 229
P position switch .................... 257
Pre-Collision System (PCS) Function ............................... 293
Warning light ........................ 558
Predictive efficient drive .......... 81
R
Radar cruise control Dynamic radar cruise control 331
Radiator ................................... 508
RCD (Rear Camera Detection) ............................................... 378Function ............................... 378
RCTA (Rear Cross Traffic Alert) ............................................... 373
RCTA Function ............................... 373
Rear Cross Traffic Alert (RCTA) ............................................... 373
Rear doors .............................. 185 Opener switch ...................... 188
Rear door child-protector lock........................................... 189
Rear seat reminder function . 188
Rear passengers’ seat belt reminder light ....................... 562
Rear seats ............................... 210 Folding down the rear seatbacks........................................... 210
Head restraints ..................... 212
Rear seat reminder function . 188
Seat heaters ......................... 443
Rear side marker lights ......... 269 Replacing exterior lights ....... 543
Switch................................... 269
Rear turn signal lights ........... 262 Replacing exterior lights ....... 543 Turn signal lever ...................262
Rear view mirror Digital Rear-view Mirror ........217
Inside rear view mirror ..........216
Outside rear view mirrors .....225
Rear window defogger ...........436
Refueling ............ .....................279
Capacity ...............................601
Fuel types .....................601, 607
Opening the fuel tank cap ....280
Regeneration Boost ...............260
Regenerative braking ...............78 Regeneration Boost..............260
Replacing Electronic key battery ...........538
Exterior lights........................543
Fuses....................................540
Tires .....................................526
Wireless remote control battery...........................................538
Replacing the tire ...................526
Reporting safety defects for Canadian owners ..................637
Reporting safety defects for U.S. owners ...................................636
Resetting the message indicat- ing maintenance is required 495
Road accident cautions ...........85
Road Sign Assist ....................329
RSA (Road Sign Assist) .........329
S
Safe Exit Assist.. .....................359
Safety Connect .........................65
Seat belt reminder light..........562
Seat belts...................................31 Adjusting the seat belt shoulder anchor height........................33
Automatic Locking Retractor ..33
Child restraint system installation .............................................55
Cleaning and maintaining the