2023 TOYOTA TUNDRA HYBRID water pump

791-4. Hybrid system
Owners Manual_USA_M0C052_en
1
For safety and security
There are air intake vents under
the rear seat for the purpose of
cooling the hybrid battery (trac-
tion 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.
NOTICE
■Hybrid battery (traction bat-
tery)
Do not carry large amounts of
water such as water cooler bottles
in the vehicle. If water spills onto
the hybrid battery (traction bat-
tery), the batte ry may be dam-
aged. Have the vehicle inspected
by your Toyota dealer.
Hybrid battery (traction
battery) air intake vents
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 (traction bat-
tery) output and a malfunction.
●Periodically clean the air intake
vents to prevent them from clog-
ging. ( P.481)
●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

4616-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_en
6
Maintenance and care
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P.535)
■Coolant selection
Only use “Toyota Super Long Life
Coolant” or a 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% deionized water.
(Minimum temperature: -31°F [-
35°C])
Canada: “Toyota Super Long Life
Coolant” is a mixture of 55% coolant
and 45% deionized water.
(Minimum temperature: -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 radiator, hoses,
engine coolant reser voir cap, inter-
coolant reservoir cap, 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 sys-
tem.
Check the radiator, condenser
and intercooler radiators and
clear away any foreign 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”
WARNING
■When the hybrid system is
hot
Do not remove the coolant reser-
voir cap.
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
Be sure to wash it off with water to
prevent it from damaging parts or
paint.
Checking the radiator,
condenser and inter-
cooler radiators
WARNING
■When the hybrid system is
hot
Do not touch the radiator, con-
denser or intercooler radiators or
condenser as they may be hot
and cause serious injuries, such
as burns.
Checking and adding the
brake fluid

4636-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_en
6
Maintenance and care
The 12-volt battery is located in
the left-hand side of the rear
seat under.
1 Raising the bottom cushion.
( P.135)
2 Remove the battery cover.
Use the flat-head screwdriver or
mechanical key ( P.110).
■Before recharging
When recharging, the 12-volt bat-
tery produces hydrogen gas which
is flammable and explosive. There-
fore, observe the following precau-
tions before recharging:
●If recharging with the 12-volt bat-
NOTICE
■Do not use any fluid other
than washer fluid
Do not use soapy water or anti-
freeze 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.
12-volt batter y
Location
Removing the 12-volt bat-
tery cover