2023 TOYOTA SIENNA HYBRID water pump

861-4. Hybrid system
of cooling the hybrid battery
(traction battery).
If the vents are blocked, it may
interfere with the cooling of the
hybrid battery (traction battery).
If input/output of the hybrid battery
(traction battery) becomes limited
and the distance that the vehicle
can be driven using the electric
motor (traction motor) is reduced,
the fuel economy may be reduced.
When a certain level of impact is
detected by the impact sensor,
the emergency shut off system
blocks the high voltage current
and stops the fuel pump to mini-
mize the risk of electrocution
and fuel leakage. If the emer-
gency shut off system activates,
your vehicle will not restart. To
restart the hybrid system, con-
tact your Toyota dealer.
A message is automatically dis-
played when a malfunction
occurs in the hybrid system or
an improper operation is
attempted.
If a warning message is shown
on the multi-information display,
read the message and follow the
instructions.
■If a warning light comes on, a
warning message is displayed,
or the 12-volt battery is discon-
nected
The hybrid system may not start. In
NOTICE
■Hybrid battery (traction bat-
tery) air intake vents
●Make sure not to block the air
intake vents with anything, such
as a seat cover, plastic cover, or
luggage. The input/output of the
hybrid battery (traction battery)
may be restricted, leading to a
reduction in hybrid battery (trac-
tion battery) output and a mal-
function.
●Periodically clean the air intake
vents to prevent them from clog-
ging. ( P.440)
●Do not get water or foreign
materials in the air intake vents
as this may cause a short circuit
and damage the hybrid battery
(traction battery).
Emergency shut off sys-
tem
Hybrid warning message

2614-3. Operating the lights and wipers
4
Driving
4 Washer/wiper dual
operation
Pushing the lever operates the
wiper and washer.
The wiper will automatically operate
a couple of times after the washer
squirts.
The washer will automatically oper-
ate and clean the camera for the
Digital Rear view Mirror
*1 (  P.194)
and rear camera
*2.
*1: If equipped
*2: Refer to “NAVIGATION AND MULTIMEDIA SYSTEM
OWNER’S MANUAL”.
■The rear window wiper and
washer can be operated when
The power swit ch is in ON.
■If no washer fluid sprays
Check that the washer nozzle is not
blocked if there is washer fluid in the
washer fluid reservoir.
■Back door opening linked rear
window wiper stop function
When the rear w indow wiper is
operating, if the back door is opened
while the vehicle is stopped, opera-
tion of the rear window wiper will be
stopped to prevent anyone near the
vehicle from being sprayed by water
from the wiper. When the back door
is closed, wiper operation will
resume.
* *
: The setting must be customized at
your Toyota dealer.
■Reverse-linked rear window
wiper function
When the shift lever is shifted to R
when the front wipers are operating,
the rear window wiper will operate
once.
■Customization
Setting of the reverse-linked func-
tion can be changed. (Customizable
features: P.546)
NOTICE
■When the washer fluid tank is
empty
Do not operate the switch continu-
ally as the washer fluid pump may
overheat.
■When a nozzle becomes
blocked
In this case, contact your Toyota
dealer.
Do not try to clear it with a pin or
other object. The nozzle will be
damaged.
■To prevent 12-volt battery dis-
charge
Do not leave the wiper on longer
than necessary when the hybrid
system is off.

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

4186-3. Do-it-yourself maintenance
J1703 brake fluid
FMVSS No.116 DOT 4 or SAE
J1704 brake fluid
Item
Clean funnel
■Brake fluid can absorb moisture
from the air
Excess moisture in the brake fluid
can cause a dangerous loss of brak-
ing efficiency. Use only newly
opened brake fluid.
If any washer does not work or
“Windshield Washer Fluid Low”
is shown on the multi-informa-
tion display, the washer tank
may be empty. Add washer
fluid.
WARNING
■When filling the reservoir
Take care as brake fluid can harm
your hands and eyes and damage
painted surfaces.
If fluid gets on your hands or in
your eyes, flush th e affected area
with clean water immediately.
If you still experien ce discomfort,
see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level
to go down slightly as the brake
pads wear out or when the fluid
level in the accumulator is high.
If the reservoir needs frequent
refilling, there may be a serious
problem.
Adding the washer fluid
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
hybrid system, 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, as
well as damaging the pump lead-
ing to problems of the washer
fluid not spraying.
■Diluting washer fluid
Dilute washer fluid with water as
necessary.
Refer to the freezing tempera-
tures listed on the label of the
washer fluid bottle.