engine TOYOTA PRIUS PLUG-IN HYBRID 2023 Repair Manual

5907-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
WARNING
■Used engine oil
● Used engine oil contains potentially harmful contaminants which may
cause skin disorders such as inflammation and skin cancer, so care
should be taken to avoid prolonged and repeated contact. To remove used
engine oil from your skin, wash thoroughly with soap and water.
● Dispose of used oil and filters only in a safe and acceptable manner. Do
not dispose of used oil and filters in household trash, in sewers or onto the
ground. Call any authorized Toyota reta iler or Toyota authorized repairer,
or any reliable repairer, service station or auto parts store for information
concerning recycling or disposal.
● Do not leave used engine oil within the reach of children.
NOTICE
■To prevent serious engine damage
Check the oil level on a regular basis.
■ When replacing the engine oil
● Be careful not to spill engine oil on the vehicle components.
● Avoid overfilling, or the engine could be damaged.
● Check the oil level on the dipstick every time you refill the vehicle.
● Be sure the engine oil filler cap is properly tightened.

5917-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
7
Maintenance and care
The coolant level is satisfactory if it is between the “MAX” and “MIN”
lines on the reservoir when the hybrid system is cold.
■Engine coolant reservoir
Reservoir cap
“MAX” line
“MIN” line
If the level is on or below the
“MIN” line, add coolant up to the
“MAX” line. ( P. 705)
■Power control unit coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the
“LOW” line, add coolant up to
the “FULL” line. ( P. 705)
Coolant
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5927-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
■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.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -35 C [-31F])
For more details about coolant, contact any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer.
■ If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/power control unit coolant reservoir
caps, drain cock and water pump.
If you cannot find a leak, have any authorized Toyota retailer or Toyota autho-
rized repairer, or any reliable repairer, test the cap and check for leaks in the
cooling system.
WARNING
■ When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps.
The cooling system may be under pressure and may spray hot coolant 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.

5937-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
7
Maintenance and care
Check the radiator and condenser and clear away any foreign objects.
If either of the above parts is extremely dirty or you are not sure of
their condition, have your vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable repairer.
Radiator and condenser
WARNING
■ When the hybrid system is hot
Do not touch the radiator or condenser as they may be hot and cause seri-
ous injuries, such as burns.
■ When the electric cooling fans are operating
Do not touch the engine compartment.
With the power switch in ON mode, the electric cooling fans may automati-
cally start to run if the air conditioning is on and/or the coolant temperature
is high. Be sure the power switch is off when working near the electric cool-
ing fans or radiator grille.

5997-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
7
Maintenance and care
WARNING
■When adding washer fluid
Do not add washer fluid when the hybrid system is hot or operating as
washer fluid contains alcohol and may catch fire if spilled on the engine etc.
NOTICE
■ Do not use any fluid other than washer fluid
Do not use soapy water or engine antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle’s painted surfaces, as well as
damaging the pump leading to problems of the washer fluid not spraying.
■ Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures list ed on the label of the washer fluid bot-
tle.

6357-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
7
Maintenance and care
Checking and replacing fuses
Turn the power switch off.
Confirm that the charging connector is not connected. Also, do not use the
Remote Air Conditioning System during the procedure.
Open the fuse box cover.
Engine compartment type A fuse box
While pushing the 2 claws, lift
up the cover.
When closing the cover, make
sure to attach the 2 claws.
Engine compartment type B fuse box
While pushing the 3 claws, lift
up the cover.
When closing the cover, make
sure to attach the 3 claws.
If any of the electrical components do not operate, a fuse may
have blown. If this happens, check and replace the fuses as nec-
essary.
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6508-1. Essential information
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
If the vehicle is submerged or water on the
road is rising
● If the door can be opened, open the door and exit the vehicle.
● If the door can not be opened, open the window using the power
window switch and ensure an escape route.
● If the window can be opened, exit the vehicle through the window.
● If the door and window cannot be opened due to the rising water,
remain calm, wait until the water level inside the vehicle rises to the
point that the water pressure inside of the vehicle equals the water
pressure outside of the vehicle and then open the door after waiting
for the rising water to enter the vehicle, and exit the vehicle. When
the outside water level exceeds half the height of the door, the door
cannot be opened from the inside due to water pressure.
■ Water level exceeds the floor
When the water level exceeds the floor and time has passed, the electrical
equipment will get damaged, the power windows will not operate, the engine
and motor stop, and the vehicle may not be able to get moving.
■ Using an emergency escape hammer*1
Laminated glass*2 is used in the windshield and the windows on this vehicle.
Laminated glass cannot be shattered with an emergency hammer*1.
*1: Contact any authorized Toyota retailer or Toyota authorized repairer, or any
reliable repairer or aftermarket access ory manufacturer for further informa-
tion about an emergency hammer.
*2: If equipped
This vehicle is not designed to be able to drive on roads that are
deeply flooded with water. Do not drive on roads where the
roads may be submerged or the water may be rising. It is dan-
gerous to remain in the vehicle, if it anticipated that the vehicle
will be flooded or set a drift. Remain calm and follow the follow-
ing.

6588-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
If you think something is wrong
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● High coolant temperature warning light flashes or comes on
● 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
● 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, spongy feeling, pedal almost touches
the floor
If you notice any of the following symptoms, your vehicle proba-
bly needs adjustment or repair. Contact any authorized Toyota
retailer or Toyota authorized repairer, or any reliable repairer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms

6608-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
Low engine oil pressure warning light
(warning buzzer)*2
Indicates that the engine oil pressure is too low
 Immediately stop the vehicle in a safe place and con-
tact any authorized Toyota retailer or Toyota autho-
rized repairer, or any reliable repairer.
Malfunction indicator lamp
Indicates a malfunction in:
• The hybrid system;
• The electronic engine control system; or
• The electronic throttle control system
 Have the vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable
repairer immediately.
SRS warning light
Indicates a malfunction in:
• The SRS airbag system; or
• The seat belt pretensioner system
 Have the vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable
repairer immediately.
ABS warning light
Indicates a malfunction in:
• The ABS; or
• The brake assist system
 Have the vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable
repairer immediately.
(Red/yellow)
Electric power steering system warning light (warning
buzzer)
Indicates a malfunction in the EPS (Electric Power Steer-
ing) system
 Have the vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable
repairer immediately.
Warning lightWarning light/Details/Actions

6618-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
8
When trouble arises
(Flashes or illuminates)
PCS warning light
• When a buzzer sounds simultaneously:
Indicates a malfunction has occurred in the PCS (Pre-
Collision System).
 Have the vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable
repairer immediately.
• When a buzzer does not sound:
The PCS (Pre-Collision System) has become temporar-
ily unavailable, corrective action may be necessary.
 Follow the instructions displayed on the multi-infor-
mation display. ( P. 366, 667)
If the PCS (Pre-Collision System) or VSC (Vehicle Stability
Control) system is disabled, the PCS warning light will illu-
minate.
 P. 378
(Orange)
LTA indicator (warning buzzer)
Indicates a malfunction in the LTA (Lane Tracing Assist)
 Follow the instructions displayed on the multi-infor-
mation display. ( P. 394)
Slip indicator light
Indicates a malfunction in:
• The VSC system;
• The TRC system; or
• The hill-start assist control system
 Have the vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable
repairer immediately.
The light will flash when the ABS, VSC or TRC system is
operating.
High coolant temperature warning light
• When the light flashes:
Indicates that the engine coolant temperature is too high
The light changes from a flashing to a solid light when
the temperature further increases
 Immediately stop the vehicle in a safe place.
( P. 705)
• When the light comes on without flashing:
Indicates a malfunction in the exhaust heat recirculator
system
 Have the vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable
repairer immediately.
Warning lightWarning light/Details/Actions