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PRIUS PRIME_OM_OM47A88U_(U)
5837-3. Do-it-yourself maintenance
7
Maintenance and care
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 your Toyota dealer, 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.
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7-3. Do-it-yourself maintenance
The coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the hybrid system is cold.
■Engine 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. 700)
■
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. 700)
Coolant
1
2
3
1
2
3
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PRIUS PRIME_OM_OM47A88U_(U)
5857-3. Do-it-yourself maintenance
7
Maintenance and care
■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% deion-
ized water. (Minimum temperature: -31 °F [-35 °C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deion-
ized water. (Minimum temperature: -44 °F [-42 °C])
For more details about coolant, contact your Toyota dealer.
■ 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 your Toyota dealer 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 stra ight 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.
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7-3. Do-it-yourself maintenance
Check the radiator and condenser and clear away any foreign objects.
If either of the above parts is ex tremely dirty or you are not sure of
their condition, have yo ur vehicle inspected by your Toyota dealer.
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, t he electric cooling fans may automati-
cally start to run if the air condition ing 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.
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PRIUS PRIME_OM_OM47A88U_(U)
5937-3. Do-it-yourself maintenance
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.
■ Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures listed on the label of the washer fluid bot-
tle.
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7-3. Do-it-yourself maintenance
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.
Left side instrument panel
Remove the lid.
Make sure to press the claw
during removal or installation.
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.
1
2
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8-2. Steps to take in an emergency
If you think something is wrong
●Fluid leaks under the vehicle
(Water dripping from the air co nditioning 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, spon gy feeling, pedal almost touches
the floor
If you notice any of the follow ing symptoms, your vehicle proba-
bly needs adjustment or repair. Contact your Toyota dealer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms
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8
When trouble arises
8-2. Steps to take in an emergency
If a warning light turns on or a warning
buzzer sounds
Calmly perform the following actions 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 occur, have the vehicle
inspected by your Toyota dealer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
Brake system warning light and warning buzzer (red
indicator)
*1
Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning
→ Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer. Continuing to drive the vehi-
cle may be dangerous.
Brake system warning light (yellow indicator)
Indicates a malfunction in:
• The regenerative braking system; or
• The electronically controlled brake system
→ Have the vehicle inspected by your Toyota dealer
immediately.
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
→ Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer.
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 your Toyota dealer.
(U.S.A.)
(Canada)
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 your Toyota dealer
immediately.