ECU TOYOTA SIENNA HYBRID 2021 (in English) Repair Manual

2224-1. Before driving
■GCWR (Gross Combination
Weight Rating)
The maximum allowable gross
combination weight. The gross
combination weight is the sum
of the total vehicle weight
(including the occupants, cargo
and any optional equipment
installed on the vehicle) and the
weight of the trailer being towed
(including the cargo in the
trailer).
■GVWR (Gross Vehicle
Weight Rating)
The maximum allowable gross
vehicle weight. The gross vehi-
cle weight is the total weight of
the vehicle. When towing a
trailer, it is the sum of the vehi-
cle weight (including the occu-
pants, cargo and any optional
equipment installed on the vehi-
cle) and the tongue weight.
■GAWR (Gross Axle Weight
Rating)
The maximum allowable gross
axle weight. The gross axle
weight is the load placed on
each axle (front and rear).
Front GAWR
WARNING
●If the gross trailer weight
exceeds unbraked TWR, trailer
brakes are required. Toyota rec-
ommends trailers with brakes
that conform to all applicable
federal and state/provincial reg-
ulations.
●Never tap into y our vehicle’s
hydraulic system, as this will
lower the vehicle’s braking
effectiveness.
●Never tow a trailer without using
a safety chain securely attached
to both the traile r and the vehi-
cle. If damage occurs to the
coupling unit or hitch ball, there
is danger of the trailer wander-
ing into another lane.
Towing related terms
A

2604-4. Refueling
1Press the opener to open the
fuel filler door.
The fuel filler doo r will open within
about 10 seconds of the switch
being pressed. Before refueling is
possible, a message will be shown
on the multi-information display in
the instrument cluster to indicate
the progress of the fuel filler door opener.
2
Turn the fuel tank cap slowly
to open it and put it into the
holder on the fuel filler door.
■If the fuel filler door cannot be
opened
 P.503
After refueling, turn the fuel tank
cap until you hear a click. Once
the cap is released, it will turn
slightly in the opposite direction.
WARNING
■When refueling
Observe the following precautions
to prevent fuel overflowing from
the fuel tank:
●Securely insert the fuel nozzle
into the fuel filler neck.
●Stop filling the tank after the fuel
nozzle automatically clicks off.
●Do not top off the fuel tank.
NOTICE
■Refueling
●Finish refueling within 30 min-
utes. If more than 30 minutes
passes, the internal valve
closes. In this condition, fuel
may overflow during the refuel-
ing process. Press the fuel filler
door opener switch again.
●Do not spill fuel during refueling.
Doing so may damage the vehi-
cle, such as causing the emis-
sion control system to operate
abnormally or damaging fuel
system components or the vehi-
cle’s painted surface.
Opening the fuel tank capClosing the fuel tank cap

2614-4. Refueling
4
Driving
■When “Check Fuel Cap” is dis-
played on the multi-information
display
The fuel tank cap may be unfas-
tened or loose. Turn the power
switch off, check the cap and tighten
it securely. If the message remains,
wait a few seconds and then turn
the power switch off once again.
WARNING
■When replacing the fuel tank
cap
Do not use anything but a genu-
ine Toyota fuel tank cap designed
for your vehicle. Doing so may
cause a fire or other incident
which may result in death or seri-
ous injury.
NOTICE
■When refueling
When refueling your vehicle,
make sure that the fuel filler door
lock is not pushed by the fuel noz-
zle boot, etc., as this may cause a
valve to close, possibly resulting
in a fuel spill.
If the fuel filler door lock has been
pushed, operate the fuel filler door
opener switch in the vehicle
before continuing to refuel.

3044-5. Using the driving support systems
●The shift lever is in a position
other than R.
●The vehicle speed is greater than
approximately 10 mph (16 km/h).
■The BSM function will detect a
vehicle when
The BSM function will detect a vehi-
cle present in the detection area in
the following situations:
●A vehicle in an adjacent lane over-
takes your vehicle.
●You overtake a vehicle in an adja-
cent lane slowly.
●Another vehicle enters the detec-
tion area when it changes lanes.
■Conditions under which the
BSM function will not detect a
vehicle
The BSM function is not designed to
detect the following types of vehi-
cles and/or objects:
●Small motorcycles, bicycles,
pedestrians, etc.*
●Vehicles traveling in the opposite
direction
●Guardrails, walls, signs, parked
vehicles and similar stationary
objects
*
●Following vehicles that are in the
same lane*
●Vehicles traveling 2 lanes away
from your vehicle*
●Vehicles which are being over-
taken rapidly by your vehicle
*: Depending on the conditions, detection of a v ehicle and/or
object may occur.
■Conditions under which the
BSM function may not function
correctly
●The BSM function may not detect
vehicles correctly in the following
situations:
• When the sensor is misaligned due to a strong impact to the sen-
sor or its surrounding area
• When mud, snow, ice, a sticker, etc. is covering the sensor or sur-
rounding area on the rear bumper
• When driving on a road surface that is wet with standing water
during bad weather, such as
heavy rain, snow, or fog
• When multiple vehicles are approaching with only a small gap
between each vehicle
• When the distance between your vehicle and a following vehicle is
short
• When there is a significant differ- ence in speed between your vehi-
cle and the vehicle that enters the
detection area
• When the difference in speed
between your vehicle and another
vehicle is changing
• When a vehicle enters a detection
area traveling at about the same
speed as your vehicle
• As your vehicle starts from a stop,
a vehicle remains in the detection
area
• When driving up and down con-
secutive steep inclines, such as
hills, dips in the road, etc.
• When driving on r oads with sharp
bends, consecutive curves, or
uneven surfaces
• When vehicle lanes are wide, or

3054-5. Using the driving support systems
4
Driving
when driving on the edge of a
lane, and the vehicle in an adja-
cent lane is far away from your
vehicle
• When an accessory (such as a hitch-mounted bicycle carrier) is
installed to the r ear of the vehicle
• When the vehicle is heavily loaded in the luggage compart-
ment
• When there is a significant differ- ence in height between your vehi-
cle and the vehicle that enters the
detection area
• Immediately after the BSM func-
tion/RCTA function are turned on
• When towing a trailer
●Instances of the BSM function
unnecessarily detecting a vehicle
and/or object may increase in the
following situations:
• When the sensor is misaligned
due to a strong impact to the sen-
sor or its surrounding area
• When the distanc e between your
vehicle and a guar drail, wall, etc.
that enters the detection area is
short
• When driving up and down con-
secutive steep inclines, such as
hills, dips in the road, etc.
• When vehicle lanes are narrow, or
when driving on the edge of a
lane, and a vehicle traveling in a
lane other than the adjacent lanes
enters the detection area
• When driving on roads with sharp bends, consecutive curves, or
uneven surfaces
• When the tires are slipping or spinning
• When the distanc e between your
vehicle and a following vehicle is
short
• When an accessory (such as a hitch-mounted bicycle carrier) is
installed to the r ear of the vehicle
• When the vehicle throws up water
or snow behind.
■Operation of the RCTA
function
The RCTA function uses radar
sensors to detect vehicles
approaching from the right or left
at the rear of the vehicle and
alerts the driver of the presence
of such vehicles by flashing the
outside rear view mirror indica-
tors and sounding a buzzer.
Approaching vehicles
Detection areas
■RCTA icon display (if
equipped)
When a vehicle approaching
from the right or left at the rear
of the vehicle is detected, the
following will be displayed on
the audio system screen.
 When the Toyota parking
assist monitor (if equipped) is
displayed
The Rear Cross Traffic
Alert function (if
equipped)
A
B

3725-3. Using the storage features
Raise the hook to use.
The cargo hooks are provided for
securing loose items.
To hang the cargo net, use the
cargo net hooks and cargo
hooks.
Pattern 1
Pattern 2
Type A
Type B (vehicles without
spare tire only)
Engage the latch buckle.
Luggage compart-
ment features
Cargo hooks
WARNING
■When cargo hooks are not in
use
To avoid injury, always return the
hooks to their stowed positions
when not in use.
Cargo net hooks
WARNING
■When the cargo net is not in
use
To avoid injury, always return the
hooks to their stowed positions
when not in use.
NOTICE
■To prevent damage to the
cargo net hooks
Avoid hanging things other than a
cargo net on them.
Side auxiliary box

3755-4. Using the other interior features
5
Interior features
Please use as a power supply
for electronic devices that use
less than 120 VAC (power con-
sumption of 1500 W).
■Using the power outlets
Rear of console box
Open the lid.
Luggage compartment
Open the lid.
■When turning the power
outlets on
1 Check that the parking brake
is engaged, and press the
power switch while depress-
ing the brake pedal.
2 Check that the READY indi-
cator is illuminated, and
press the AC120V switch.
The power outlets can be used
when the indicator on the AC120V
switch is illuminated.
The power outlets are turned off/on
each time the AC120V switch is
pressed.
■When connecting a device
Open the lid, and fully and
securely insert the plug of the
device into the power outlet.
NOTICE
■When power outlet is not in
use
To avoid damaging the power out-
let, close the p ower outlet lid
when the power outlet is not in
use.
Foreign objects or liquids that
enter the power outlet may cause
a short circuit.
■To prevent blown fuse
Do not use an accessory that
uses more than 12 V 10 A.
■To prevent 12-volt battery dis-
charge
Do not use the power outlet lon-
ger than necessary when the
hybrid system is off.
Power outlets (120 VAC)
(if equipped)

3775-4. Using the other interior features
5
Interior features
stable power supply
●Devices that require a constant
power supply from the power out-
let, such as a device with a timer.
■When the 120 VAC power out-
lets cannot be used
If the AC120V switch is pressed but
the switch indicator does not illumi-
nate, the protection circuit may have
operated.
In this case, perform the appropriate
procedures as follows.
●Disconnect the plug of each
device from the p ower outlets,
check that the total power con-
sumption of all devices to be con-
nected to the power outlets is less
than 1500 W and check that the
devices are not malfunctioning,
reconnect the devices and then
press the AC120V switch again.
●Check the charge of the hybrid
battery (traction battery)
(  P.122). If the charge is low,
shift the shift lever to P, allow the
engine to run to charge the hybrid
battery (traction battery), and then
press the AC120V switch again.
●If the temperature inside the vehi-
cle is high, such as after the vehi-
cle has been park ed in the sun,
use the air conditioning system to
sufficiently ventilate or cool the
interior, and then press the
AC120V switch again.
●If the vehicle has been stopped in
a cold area, to pro tect the hybrid
battery (traction battery), the
power outlets may not be able to
be used. In this case, drive the
vehicle for a while to warm up the
hybrid battery (traction battery),
and then press the AC120V
switch again.
If the power outlets cannot be used
even after performing the appropri-
ate procedures above, have the
vehicle inspected by your Toyota
dealer.
WARNING
■For safe use
Observe the following precau-
tions.
Failure to do so may lead to an
accident, resulting in death or
serious injury.
●Do not use devices such as the
following when driving:
• Devices which cannot be prop- erly secured within the vehicle.
• Devices which may distract the driver and be a hinderance to
safe driving, such as a TV, DVD
player, etc.
• Unsecured devices which gen- erate heat, such as a toaster,
microwave, electric heater,
electric kettle, coffee maker,
etc., as they may cause burns
or a fire in the case of sudden
braking or an accident.
• Devices which may fall under the pedals and prevent the
brake pedal from being
depressed.
●Do not use devices which pro-
duce steam while the windows
are closed. Doing so may cause
the windows to fog up, reducing
visibility and making it difficult to
drive safely. Also, the steam
may damage or negatively
affect other devices.
●Do not connect a malfunctioning
device to a power outlet, as
doing so may cause the power
outlets to become inoperable.
●Do not disconnect the plug of a
device while your hands are wet
or insert a pin or other object
into the power ou tlet. Also, if a
liquid or snow is on the power
outlet, dry the outlet before
using it.

3895-4. Using the other interior features
5
Interior features
■Things unsuitable for the refrig-
erator
●Drinks in unsealed containers
●Fragile things, perishables or any-
thing with strong odor
■To use the refrigerator effec-
tively
●Do not keep too many things in
the refrigerator.
●Cool things in advance before it is
put in the refrigerator. Especially,
hot things should be cooled off.
●When storing watery things, wrap
them up.
●Before using the freeze mode,
make sure that all items in the
cooler box are suitable for freez-
ing.
●To prevent the inside temperature
from getting higher, avoid stop-
ping the hybrid system for a long
time when using the refrigerator.
■After using the refrigerator
Water droplets inside of the refriger-
ator may cause an odor. It is recom-
mended to frequently wipe off water
droplets.
■Cleaning the refrigerator
Clean the inside o f the refrigerator
using a soft cloth dampened with a
diluted neutral detergent, and then
make sure to dry.
■Location of the compo-
nents
Vacuum port
Vacuum cleaner switch
Hose
Cleaning heads
■Before using the vacuum
cleaner
 Stop the vehicle in a safe
place.
 Set the parking brake.
 Shift the shift lever to P.
 Make sure the power switch is
in ON.
 Make sure the vacuum dust
bin is securely installed.
 Make sure the pre-filter and
main-filter are securely
installed in the dust bin.
WARNING
■Caution while driving
Always keep the refrigerator
closed to reduce the chance of
injury in case of an accident or
sudden stop.
NOTICE
■To prevent battery discharge
Do not leave the refrigerator on
longer than necessary when the
hybrid system is not running.
Vacuum cleaner (if
equipped)
A
B
C
D

3905-4. Using the other interior features
■When using the vacuum
cleaner
1 Open the lid and install the
hose and cleaning head.
Make sure that the hose and clean-
ing head are securely installed.
2 Press the switch.
The vacuum cleaner can be used
when the indicator on the switch is
illuminated.
The vacuum cleaner is turned
off/on each time the switch is
pressed.
■After using the vacuum
cleaner
1 Remove the hose and clean-
ing head and stow them. 2
Remove the access panel.
3 Rotate the handle counter-
clockwise, and lift up and pull
the handle to take out the
dust bin.
4 Open the lid and check the
dust bin, and empty it if nec-
essary.
5 To reinstall the dust bin,
make sure that the handle is