2023 TOYOTA SIENNA HYBRID check engine

4046-2. Maintenance
General maintenance
Listed below are the general
maintenance items that
should be performed at the
intervals specified in the
“Owner’s Warranty Informa-
tion Booklet” or “Owner’s
Manual Supplement/Sched-
uled Maintenance Guide”. It
is recommended that any
problem you notice should
be brought to the attention
of your Toyota dealer or
qualified service shop for
advice.
WARNING
■If the hybrid system is run-
ning
Turn the hybrid system off and
ensure that there is adequate
ventilation before performing
maintenance checks.
Engine compartment
ItemsCheck points
Brake fluid
Is the brake fluid at
the correct level?
(  P.417)
Engine/power
control unit
coolant
Is the
engine/power con-
trol unit coolant at
the correct level?
( P.416)
Engine oil
Is the engine oil at
the correct level?
( P.413)
Exhaust sys-
temThere should not
be any fumes or
strange sounds.
Radiator/con-
denser
The radiator and
condenser should
be free from for-
eign objects.
( P.417)
Washer fluid
Is there sufficient
washer fluid?
( P.418)
Luggage compartment
ItemsCheck points
12-volt batteryCheck the connec-
tions. ( P.419)
Vehicle interior
ItemsCheck points
Accelerator
pedal
• The accelerator
pedal should
move smoothly
(without uneven
pedal effort or
catching).
Hybrid trans-
mission “Park”
mechanism
• When parked on a slope and the
shift lever is in P,
is the vehicle
securely
stopped?
ItemsCheck points

4066-2. Maintenance
The OBD system determines
that a problem exists some-
where in the emission control
system. Your vehicle may not
pass the I/M test and may need
to be repaired. Contact your
Toyota dealer to service the
vehicle.
When the 12-volt battery is
disconnected or discharged
Readiness codes that are set
during ordinary driving are
erased.
Also, depending on your driv-
ing habits, the readiness
codes may not be completely
set.
 When the fuel tank cap is
Vehicle exterior
ItemsCheck points
Doors
• Do the doors
operate
smoothly?
Engine hood
• Does the engine hood lock system
work properly?
Fluid leaks
• There should not be any signs of
fluid leakage
after the vehicle
has been parked.
Tires
• Is the tire infla-tion pressure
correct?
• The tires should not be damaged
or excessively
worn.
• Have the tires been rotated
according to the
maintenance
schedule?
• The wheel nuts should not be
loose.
Windshield
wipers/rear
window wiper
• The wiper blades should not show
any signs of
cracking, split-
ting, wear, con-
tamination or
deformation.
• The wiper blades should clear the
windshield/rear
window without
streaking or skip-
ping.
Emission inspection
and maintenance (I/M)
programs
Some states have vehicle
emission inspection pro-
grams which include OBD
(On Board Diagnostics)
checks. The OBD system
monitors the operation of
the emission control sys-
tem.
If the malfunction indica-
tor lamp comes on
Your vehicle may not
pass the I/M test in the fol-
lowing situations:

4146-3. Do-it-yourself maintenance
check the oil level on the dip-
stick.
■Checking the engine oil
1 Park the vehicle on level
ground. After warming up the
engine and turning off the
engine, wait more than 5
minutes for the oil to drain
back into the bottom of the
engine.
2 Holding a rag under the end,
pull the dipstick out.
3 Wipe the dipstick clean.
4 Reinsert the dipstick fully.
5 Holding a rag under the end,
pull the dipstick out and
check the oil level.
Low
Normal
Excessive
The shape of the dipstick may differ
depending on the type of vehicle or
engine.
6Wipe the dipstick and reinsert
it fully.
■Checking the oil type and
preparing the items needed
Make sure to check the oil type
and prepare the items needed
before adding oil.
 Engine oil selection
P.519
 Oil quantity (Low  Full)
1.6 qt. (1.5 L, 1.3 Imp. qt.)
 Item
Clean funnel
■Adding engine oil
If the oil level is below or near
the low level mark, add engine
oil of the same type as that
already in the engine.
1 Remove the oil filler cap by
turning it counterclockwise.
2 Add engine oil slowly, check-
ing the dipstick.
3 Install the oil filler cap by
turning it clockwise.
A
B
C

4156-3. Do-it-yourself maintenance
6
Maintenance and care
■Engine oil consumption
A certain amount of engine oil will
be consumed while driving. In the
following situatio ns, oil consump-
tion may increase, and engine oil
may need to be ref illed in between
oil maintenance intervals.
●When the engine is new, for
example directly after purchasing
the vehicle or after replacing the
engine
●If low quality oil or oil of an inap-
propriate viscosity is used
●When driving at high engine
speeds or with a heavy load,
when towing, or when driving
while accelerating o r decelerating
frequently
●When leaving the engine idling for
a long time, or wh en driving fre-
quently through heavy traffic
■After changing the engine oil
The engine oil maintenance data
should be reset. Perform the follow-
ing procedures:
4.2-inch display
1 Press or of the meter
control switches to select on
the multi-information display.
2 Press or of the meter
control switches, select “Vehicle
Settings” and then press and
hold “OK”.
7-inch display
1 Press or of the meter
control switches to select on
the multi-information display.
2 Press or of the meter
control switches, select and
then press and hold “OK”.
3 Press or of the meter
control switch es, select “Oil Maintenance” and then press
“OK”.
4 Select “Yes” and press “OK”.
A message will be displayed on the
multi-informat ion display.
WARNING
■Used engine oil
●Used engine oil contains poten-
tially 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 h ousehold trash,
in sewers or onto the ground.
Call your Toyota dealer, service
station or auto parts store for
information concerning recy-
cling or disposal.
●Do not leave used engine oil
within the reach of children.
NOTICE
■To prevent serious engine
damage
Check the oil le vel 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 dip-
stick every time you refill the
vehicle.

4166-3. 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.509)
■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.510)
■Coolant selection
Only use “Toyota Super Long Life
Coolant” or a similar high quality
ethylene glycol ba sed 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% c oolant and 50%
deionized water. (Minimum tem-
perature: -31°F [-35°C])
Canada:
“Toyota Super Long Life Coolant” is
a mixture of 55% c oolant and 45%
deionized water. (Minimum tem-
perature: -44°F [-42°C])
For more details about coolant, con-
tact your Toyota dealer.
■If the coolant level drops within
a short time of replenishing
Visually check the radiators, 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
NOTICE
●Be sure the engine oil filler cap
is properly tightened.
■If oil is spilled on the engine
cover
To prevent the engine cover from
being damaged, remove any
engine oil from the engine cover
as soon as possible using a neu-
tral detergent. Do not use an
organic solvent such as brake
cleaner.
Checking the coolant
A
B
C
A
B
C

4176-3. Do-it-yourself maintenance
6
Maintenance and care
check for leaks in the cooling sys-
tem.
Check the radiator and con-
denser, and clear away any for-
eign objects.
If either of the above parts is
extremely dirty or you are not
sure of their condition, have
your vehicle inspected by your
Toyota dealer.
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
■Adding fluid
Make sure to check the fluid
type and prepare the necessary
item.
 Fluid type
FMVSS No.116 DOT 3 or SAE
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 cool-
ant 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
B e s ur e t o wa sh it o ff w ith w at er to
prevent it from d amaging parts or
paint.
Checking the radiator and
condenser
WARNING
■When the hybrid system is
hot
Do not touch the radiator or con-
denser as they may be hot and
cause serious injuries, such as
burns.
■When the electric cooling fan
is operating
Do not touch the engine compart-
ment.
With the power switch in ON, the
electric cooling fa n may automati-
cally start to run if the air condi-
tioning is on and/or the coolant
temperature is high. Be sure the
power switch is OFF when work-
ing near the electric cooling fan or
radiator grille.
Checking and adding the
brake fluid

4466-3. Do-it-yourself maintenance
1Turn the power switch off.
2 Open the fuse box cover.
Engine compartment
Push claw , and to com-
pletely release the lock, and then lift
up the cover.
Left side instrument panel
Remove the lid.
Right side luggage compart-
ment
Remove the cover
3Remove the fuse.
Only type A fuse c an be removed
using the pullout tool.
4 Check if the fuse is blown.
Replace the blown fuse with a new
fuse of an appropriate amperage
rating. The amperage rating can be
found on the fuse box lid.
Type A
Normal fuse
Checking and replac-
ing fuses
If any of the electrical com-
ponents do not operate, a
fuse may have blown. If this
happens, check and replace
the fuses as necessary.
Checking and replacing
fuses
ABC
A

4777-2. Steps to take in an emergency
7
When trouble arises
instructions (P.512).
●If any of the following messages
are shown on the multi-informa-
tion display, it may indicate a mal-
function. Have the vehicle
inspected by your Toyota dealer
immediately.
• “Smart Key System Malfunction”
• “Hybrid System Malfunction”
• “Check Engine”
• “Hybrid Battery System Malfunc-
tion”
• “Accelerator Syst em Malfunction”
●If any of the following messages
are shown on the multi-informa-
tion display, it may indicate a mal-
function. Immediately stop the
vehicle and contact your Toyota
dealer.
•“Braking Power Low”
• “12-Volt Battery Charging System Malfunction”
• “Oil Pressure Low”
●If any of the following messages
are shown on the multi-informa-
tion display, the vehicle may have
run out of fuel. Stop the vehicle in
a safe place and, if the fuel level is
low, refuel the vehicle.
• “Hybrid System Stopped”
• “Engine Stopped”
●If “Low Auxiliary Battery See
Owner’s Manual” is shown
• When the display goes off after
several seconds
*:
Maintain the hybri d system opera-
tion for more than 15 minutes and
charge the 12- volt battery.
• When the display does not go off:
Start up the hybrid system using the
procedures for “If the 12-volt battery
is discharged” ( P.504)
*: Displays for about 6 seconds
●If “Maintenance Required for Trac-
tion Battery Cooling Parts See
Owner’s Manual” is shown, the fil-
ter may be clogged, the air intake
vent may be blocked, or there may
be a gap in the duct. Therefore, perform the follo
wing correction
procedure.
• Cleaning the hybrid battery (trac-
tion battery) air intake vents
(
P.440)
If the warning message is shown
even if the vents are cleaned,
have the vehicle inspected by
your Toyota dealer.
■If “Engine Oil Level Low Add or
Replace” is displayed
The engine oil level may be low.
Check the level o f the engine oil,
and add engine oil if necessary.
This message may be displayed if
the vehicle is stopped on a slope.
Move the vehicle to a level surface
and check if the message disap-
pears.
■If “Hybrid System Stopped
Steering Power Low” is dis-
played
This message is displayed if the
hybrid system is stopped while driv-
ing.
When steering wheel operations are
heavier than usual, grip the steering
wheel firmly and operate it using
more force than usual.
■If “Hybrid System Overheated
Output Power Reduced” is
shown
The message may be shown when
driving under severe operating con-
ditions. (For example, when driving
up a long steep hill or driving up a
steep hill in reverse.)
Coping method: P.512
■If “Traction Battery Needs to be
Protected Refrain from the Use
of N Position” is shown
This message may be displayed
when the shift lever is in N.
As the hybrid battery (traction bat-
tery) can not be charged when the
shift lever is in N, shift the shift lever
to P when the vehicle is stopped.