service TOYOTA SIENNA HYBRID 2021 (in English) Owner's Manual

4456-3. Do-it-yourself maintenance
6
Maintenance and care
7Install the air intake vent
cover.
Insert the tab of the cover as shown
in the illustrati on and push the
cover to engage the claws.
8 Using a Phillips screwdriver,
install the clip.
■Scheduled maintenance of the
air intake vents is necessary
when
In some situations such as when the
vehicle is used frequently or in
heavy traffic or dusty areas, the air
intake vents may need to be
cleaned more regularly. For details,
refer to “Scheduled Maintenance
Guide” or “Owner’s Manual Supple-
ment”.
■Cleaning the air intake vents
●Dust in the air in take vents may
interfere with the cooling of the
hybrid battery (traction battery). If
charging/discharging of the hybrid
battery (traction battery) becomes
limited, the distance that the vehi-
cle can be driven using the electric motor (traction motor) may be
reduced and the fuel economy
may be reduced. Inspect and
clean the air intake vents periodi-
cally.
●Improper handling of the air intake
vent covers and filters may result
in damage to them. If you have
any concerns about cleaning the
filters, contact your Toyota dealer.
■If “Maintenance Required for
Traction Battery Cooling Parts
See Owner’s Manual” is shown
on the multi-information display
●If this warning message is shown
on the multi-information display,
remove the air intake vent covers
and clean the filters. (
P.444)
●After cleaning the air intake vents,
start the hybrid system and check
that the warning message is no
longer shown.
It may take approximately 20 min-
utes after the hybrid system is
started until the warning message
disappears. If the warning mes-
sage does not disappear, have
the vehicle inspected by your
Toyota dealer.
WARNING
■When cleaning the air intake
vents
●Do not use water or other liq-
uids to clean the air intake
vents. If water is applied to the
hybrid battery (traction battery)
or other components, a mal-
function or fire may occur.
●Before cleaning the air intake
vents, make sure to turn the
power switch off to stop the
hybrid system.
■When removing the air intake
vent covers
Do not touch the service plug
located underneath the console
box. ( P.84)

4627-2. Steps to take in an emergency
7-2.Steps to take in an emergency
If your vehicle needs
to be towed
If towing is necessary, we
recommend having your
vehicle towed by your
Toyota dealer or commer-
cial towing service, using a
wheel-lift type truck or flat-
bed truck.
Use a safety chain system
for all towing, and abide by
all state/provincial and local
laws.
2WD models: If towing your
vehicle with a wheel-lift type
truck from the front, the
vehicle’s rear wheels and
axles must be in good con-
ditions. (P.462, 463)
If they are damaged, use a
towing dolly or flatbed
truck.
AWD models: If towing your
vehicle with a wheel-lift type
truck, use a towing dolly.
( P.462, 463)
WARNING
Observe the following precau-
tions. Failure to do so may result
in death or serious injury.
■When towing the vehicle
2WD models: Be sure to transport
the vehicle with th e front wheels
raised or with all four wheels
raised off the ground. If the vehi-
cle is towed with th e front wheels
contacting the ground, the drive-
train and related parts may be
damaged or electricity generated
by the operation of the motor may
cause a fire to occur depending
on the nature of the damage or
malfunction.
AWD models: Be sure to transport
the vehicle with all four wheels
raised off the ground. If the vehi-
cle is towed with th e tires contact-
ing the ground, the drivetrain or
related parts may be damaged,
the vehicle may fly off the truck, or
electricity generated by the opera-
tion of the motor may cause a fire
to occur depending on the nature
of the damage or malfunction.

4637-2. Steps to take in an emergency
7
When trouble arises
The following may indicate a
problem with your transmission.
Contact your Toyota dealer or
commercial towing service
before towing. 
The hybrid system warning
message is shown on the
multi-information display and
the vehicle does not move.
 The vehicle makes an abnor-
mal sound.
From the front (2WD models)
Release the parking brake.
Turn automatic mode off.
( P.244)
From the front (AWD models)
Use a towing dolly under the
rear wheels.
NOTICE
■To prevent damage to the
vehicle when towing using a
wheel-lift type truck
●Do not tow the vehicle from the
rear when the power switch is
off. The steering lock mecha-
nism is not strong enough to
hold the front wheels straight.
●When raising the vehicle,
ensure adequate ground clear-
ance for towing at the opposite
end of the raised vehicle. With-
out adequate clearance, the
vehicle could be damaged while
being towed.
■To prevent damage to the
vehicle when towing with a
sling-type truck
Do not tow with a sling-type truck,
either from the front or rear.
■Recreational towing (behind
motor home, etc.)
Never dinghy tow your vehicle to
prevent causing serious damage
to the AWD system and transmis-
sion. ( P.230)
Situations when it is nec-
essary to contact dealers
before towing
Towing with a wheel-lift
type truck

5298-1. Specifications
8
Vehicle specifications
emission control system may be
adversely affected.
The malfunction indicator lamp on
the instrument cluster may come on.
If this happens, contact your Toyota
dealer for service.
■If your engine knocks
●Consult your Toyota dealer.
●You may occasionally notice light
knocking for a short time while
accelerating or driving uphill. This
is normal and there is no need for
concern.
NOTICE
■Notice on fuel quality
●Do not use impro per fuels. If
improper fuels are used, the
engine will be damaged.
●Do not use leaded gasoline.
Leaded gasoline can cause
damage to your vehicle’s three-
way catalytic converters caus-
ing the emission control system
to malfunction.
●Do not use gasohol other than
the type previously stated.
Other gasohol may cause fuel
system damage or vehicle per-
formance problems.
●Using unleaded gasoline with
an octane number or rating
lower than the l evel previously
stated will cause persistent
heavy knocking.
At worst, this will lead to engine
damage.
■Fuel-related poor driveability
If poor driveability (poor hot start-
ing, vaporization, engine knock-
ing, etc.) is encountered after
using a different type of fuel, dis-
continue the use of that type of
fuel.
■When refueling with gasohol
Take care not to spill gasohol. It
can damage your vehicle’s paint.

Alphabetical Index581
Digital Rear-view Mirror........ 192
Inside rear view mirror.......... 187
Intuitive parking assist .......... 308
LTA (Lane Tracing Assist).... 275
Parking Support Brake function (rear-crossing vehicles) ...... 301
Parking Support Brake function (static objects) .................... 308
Rain-sensing windshield wipers ........................................... 256
RCTA ................................... 301
Toyota Safety Sense ............ 262
Service plug .............................. 83
Shift lever ................................ 238 If the shift lever cannot be shifted from P................................. 240
Shift lock system .................... 240
Shopping bag hooks .............. 387
Side airbags .............................. 41
Side auxiliary box ................... 372
Side marker lights Light switch .......................... 248
Replacing light bulbs ............ 451
Side mirrors ............................ 198 Adjustment ........................... 198
BSM (Blind Spot Monitor)..... 300
Folding ................................. 199
Heaters................................. 350
Linked mirror function when reversing ............................ 199
Side turn signal lights Replacing light bulbs ............ 451
Turn signal lever................... 242
Side windows ...... ................... 201
Sliding doors Canceling the power sliding door system ................................ 148
Hands Free Power Sliding doors
........................................... 141
Keyless entry........................ 138
Power sliding doors .............. 137
Sliding door child -protectors. 142 Wireless remote control........139
Smart key system ...................164 Antenna location...................164
Entry functions......132, 138, 151
Starting the hybrid system ....231
Warning message . ...............477
Snow tires ...............................343
Spare tire Storage location ...................492
Specifications .........................518
Speedometer .....................97, 101
Sport mode..............................333
Steering lock Column lock releas e .............232
Steering lock system warning message .............................232
Steering wheel Adjustment ...........................185
Heated steering wheel..........361
Meter control switches..........105
Stop lights Replacing light bulbs ............451
Storage feature .. .....................366
Storage precaution s ...............367
Stuck If the vehicle becomes stuck 514
Suggestion functi on ...............117
Sunglass holder.... ..................370
Sunshade ........................204, 385
Sunshades ..............................385
Sun visors ...............................374
Switches “ODO TRIP”switch ..........99, 103
“SOS” button ..........................75
Automatic High Beam switch 250
Brake hold switch .................246
BSM (Blind Spot M onitor) .....301
Digital Rear-view Mirror control switches..............................188
Door lock switch ...................135
Driving mode select switch ...333
Driving position memory