Page 486 of 672
486
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7-3. Do-it-yourself maintenance
Engine compartment
Washer fluid tank (P. 495)
Engine oil filler cap  ( P. 488)
Engine oil level dipstick  ( P. 487)
Engine coolant reservoir  ( P. 489) Brake fluid reservoir (
P. 491)
Fuse box  ( P. 514)
Battery  ( P. 492)
Electric cooling fans
Condenser  ( P. 491)
Radiator  (P. 491)1
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SIENNA_OM_OM08007U_(U)
4897-3. Do-it-yourself maintenance
7
Maintenance and care
The coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the engine is cold.Reservoir cap
“FULL” line
“LOW” line
If  the  level  is  on  or  below  the
“LOW”  line,  add  coolant  up  to  the
“FULL” line.
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.
Engine coolant
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7-3. Do-it-yourself maintenance
■Coolant selection
Only  use  “Toyota  Super  Long  Life  Coolant”  or  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 engine coolant, contact your Toyota dealer.
■ If the coolant level drops within a short time of replenishing
Visually  check  the  radiator,  hoses,  engine  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 engine is hot
Do not remove the engine coolant reservoir cap. 
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. 
     
        
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5958-2. Steps to take in an emergency
SIENNA_OM_OM08007U_(U)
8
When trouble arises
The  coolant  level  is  satisfactory if  it  is  between  the  “FULL”  and
“LOW” lines on the reservoir.
Reservoir
“FULL” line
“LOW” line
Radiator cap
Add coolant if necessary.
Water  can  be  used  in  an  emer-
gency if coolant is unavailable.
Start  the  engine  and  turn  the  air  conditioning  system  on  to  check
that the radiator cooling fans oper ate and to check for coolant leaks
from the radiator or hoses.
The  fans  operate  when  the  air  conditioning  system  is  turned  on  immedi-
ately after a cold start. Confirm that  the fans are operating by checking the
fan sound and air flow. If it is difficult to check these, turn the air condition-
ing  system  on  and  off  repeatedly.  (The  fans  may  not  operate  in  freezing
temperatures.)
If the fans are not operating:
Stop the engine immediately an d contact your Toyota dealer.
If the fans are operating:
Have the vehicle in spected at the nearest Toyota dealer.
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        Page 596 of 672

5968-2. Steps to take in an emergency
SIENNA_OM_OM08007U_(U)
WARNING
■When inspecting under the hood of your vehicle
Observe the following precautions. 
Failure to do so may result in serious injury such as burns.
●If  steam  is  seen  coming  from  under  the  hood,  do  not  open  the  hood  until
the steam has subsided. The engine compartment may be very hot.
● Keep hands and clothing (especially a tie, a scarf or a muffler) away from
the  fan and  belts. Failure to  do so  may  cause the  hands or  clothing to  be
caught.
● Do  not  loosen  the  radiator  cap  or  the  coolant  reservoir  cap  while  the
engine  and  radiator  are  hot.  High  temperature  steam  or  coolant  could
spray out.
NOTICE
■When adding engine coolant
Add  coolant  slowly  after  the  engine  has  cooled  down  sufficiently.  Adding
cool coolant to a hot engine too quickly can cause damage to the engine.
■ To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust
etc.).
● Do not use any coolant additive.