2022 TOYOTA BZ4X cool

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7-3. Do-it-yourself maintenance
WARNING
The motor compartment contains many mechanisms and fluids that
may move suddenly, become hot, or become electrically energized. To avoid death or serious injury, observe
the following precautions.
■When working on the motor com-
partment
●Make sure that “POWER ON” on the multi-information display and
the “READY” indicator are both off.
●Keep hands, clothing and tools
away from the moving fan.
●Be careful not to touch the motor,
power control unit, radiator, etc., right after driving as they may be hot. Coolant and other fluids may
also be hot.
●Do not leave anything that may
burn easily, such as paper and rags, in the motor compartment.
●Do not smoke, cause sparks or expose an open flame to the 12-volt battery. 12-volt battery fumes are
flammable.
●Be extremely cautious when work-
ing on the 12-volt battery. It con- tains poisonous and corrosive sulfuric acid.
●Never touch, disassemble, remove or replace the high voltage parts,
cables and their connectors. It can cause severe burns or electric shock that may result in death or
serious injury.
●Take care because brake fluid can
harm your hands or eyes and dam- age painted surfaces. If fluid gets on your hands or in your eyes, flush
the affected area with clean water immediately. If you still experience discomfort, consult a doctor.
■When working near the electric cooling fan or radiator grille
Be sure the power switch is OFF.
With the power switch in ON, the electric cooling fan may automatically start to run if the air conditioning is on
and/or the coolant temperature is high. ( P.471)
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc.,
from getting in your eyes.
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 or when the fluid level in the accumulator is high.
If the reservoir needs frequent refill- ing, it may indicate a serious problem.

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7-3. Do-it-yourself maintenance
Heater coolant reservoir (P.470)
Washer fluid tank ( P.475)
Power control unit coolant reservoir ( P.472)
12-volt battery ( P.473)
Fuse box ( P.501)
Radiator ( P.471)
Condenser ( P.471)
Electric cooling fan
The coolant level is satisfactory if it
is between the “MAX” and “MIN”
lines on the reservoir when the EV
system is cold.
Motor compartment
Components
Checking the heater coolant

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7-3. Do-it-yourself maintenance
Maintenance and care
Reservoir cap
“MAX” line
“MIN” line
If the level is on or below the “MIN” line,
add coolant up to the “MAX” line.
( P.549)
■Coolant selection
Only use “Toyota Super Long Life Cool- ant” 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.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -35°C [-31°F])
For more details about coolant, contact
any authorized Toyota retailer or Toyota authorized repairer, or any reliable repairer.
■If the coolant level drops within a
short time of replenishing
Visually check the radiator, hoses, power control unit coolant reservoir
caps, drain cock and water pump.
If you cannot find a leak, have any authorized Toyota retailer or Toyota
authorized repairer, or any reliable repairer, test the cap and check for leaks in the cooling system.
Check the radiator and condenser
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 any authorized Toyota
retailer or Toyota authorized
repairer, or any reliable repairer.
WARNING
■When the EV system is hot
Do not remove the power control unit
coolant reservoir caps.
The cooling system may be under pressure and may spray hot coolant 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 mix-
ture 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 and
condenser
WARNING
■When the EV system is hot
Do not touch the radiator or con-
denser as they may be hot and cause serious injuries, such as burns.

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7-3. Do-it-yourself maintenance
The coolant level is satisfactory if it
is between the “MAX” and “MIN”
lines on the reservoir when the EV
system is cold.
Reservoir cap
“MAX” line
“MIN” line
If the level is on or below the “MIN” line,
add coolant up to the “MAX” line.
■Coolant selection
In order to ensure maximum perfor-
mance of the traction battery cooling system and limit risks of battery short-circuit and other damage to your vehi-
cle, Toyota recommends using “Toyota Genuine Traction Battery Coolant” or
similar high-quality ethylene glycol-
based, low electric conductivity coolant, non-amine and non-borate coolant with azole additives.
Toyota cannot guarantee that the use of a product other than “Toyota Genuine Traction Battery Coolant” will prevent
risks of battery short-circuit or other damage.
Never use water as it will cause dam-
age.
Do not reuse coolant that has been removed from the radiator.
For more details about coolant, contact any authorized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
■If the coolant level drops within a short time of replenishing
Visually check the hoses, heater coolant
reservoir caps, drain cock and water pump.
If you cannot find a leak, have any
authorized Toyota retailer or Toyota authorized repairer, or any reliable repairer, test the cap and check for leaks
in the cooling system.
WARNING
■When the electric cooling fan is operating
Do not touch the motor compartment.
With the power switch in ON, the electric cooling fan may automatically
start to run if the air conditioning is on and/or the coolant temperature is high. Be sure the power switch is OFF
when working near the electric cool- ing fan or radiator grille.
Checking the power control
unit coolant
WARNING
■When the heater system is hot
Do not remove the heater coolant res-
ervoir caps.
The heater system may be under pressure and may spray hot coolant if
the cap is removed, causing serious injuries, such as burns.

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7-3. Do-it-yourself maintenance
Maintenance and care
Check the 12-volt battery as fol-
lows.
■12-volt battery exterior
Make sure that the 12-volt battery
terminals are not corroded and that
there are no loose connections,
cracks, or loose clamps.
Terminals
Hold-down clamp
■Checking 12-volt battery fluid
Check that the level is between the
“UPPER LEVEL” and “LOWER
LEVEL” lines.
“UPPER LEVEL” line
“LOWER LEVEL” line
If the fluid level is at or below the
“LOWER LEVEL” line, add distilled
water.
■Adding distilled water
1 Remove the vent plug.
2 Add distilled water.
If the “UPPER LEVEL” cannot be seen,
check the fluid level by looking directly at the cell.
3 Put the vent plug back on and
close it securely.
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flam-mable and explosive. Therefore,
observe the following precautions before recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to dis-
NOTICE
■When adding coolant
Coolant is neither plain water nor
straight antifreeze. The correct mix- ture 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 12-volt battery

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8-2. Steps to take in an emergency
For details, consult with at any autho-
rized Toyota retailer or Toyota autho- rized repairer, or any reliable repairer as soon as possible.
WARNING
■When removing the 12-volt bat-tery terminals
Always remove the negative (-) termi-
nal first. If the positive (+) terminal contacts any metal in the surrounding area when the positive (+) terminal is
removed, a spark may occur, leading to a fire in addition to electrical shocks and death or serious injury.
■Avoiding 12-volt battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flam-mable gas that may be emitted from
the 12-volt battery:
●Make sure each jumper cable is connected to the correct terminal
and that it is not unintentionally in contact with any other than the intended terminal.
●Do not allow the other end of the jumper cable connected to the “+”
terminal to come into contact with any other parts or metal surfaces in the area, such as brackets or
unpainted metal.
●Do not allow the + and - clamps of
the jumper cables to come into con- tact with each other.
●Do not smoke, use matches, ciga-rette lighters or allow open flame near the 12-volt battery.
■12-volt battery precautions
The 12-volt battery contains poison- ous and corrosive acidic electrolyte,
while related parts contain lead and lead compounds. Observe the follow-ing precautions when handling the
12-volt battery:
●When working with the 12-volt bat- tery, always wear safety glasses
and take care not to allow any bat- tery fluids (acid) to come into con-tact with skin, clothing or the vehicle
body.
●Do not lean over the 12-volt battery.
●In the event that battery fluid (acid) comes into contact with the skin or
eyes, immediately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention can be received.
●Always wash your hands after han-dling the 12-volt battery and other
battery-related parts.
●Do not allow children near the 12-
volt battery.
■When replacing the 12-volt bat-
tery
●When the vent plug is close to the hold down clamp, the battery fluid
(acid) may leak.
●For information regarding battery
replacement, contact any autho- rized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
NOTICE
■When handling jumper cables
When connecting the jumper cables,
ensure that they do not become entangled in the cooling fan.

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8-2. Steps to take in an emergency
When trouble arises
1Stop the vehicle in a safe place
and turn off the air conditioning
system.
2 Leave the EV system operating
and carefully lift the hood.
3 Check if the cooling fan is oper-
ating.
If the fan is operating:
Wait until the “EV System over-
heated Output power reduced”
message disappears and then
stop the EV system. If the mes-
sage does not disappear, call
any authorized Toyota retailer or
Toyota authorized repairer, or
any reliable repairer.
If the fan is not operating:
Stop the EV system immediately
and call any authorized Toyota
retailer or Toyota authorized
repairer, or any reliable repairer.
4 After the EV system has cooled
down, inspect the hoses and
radiator core (radiator) for any
leaks.
Radiator
Cooling fan
If a large amount of coolant leaks,
immediately contact any authorized
Toyota retailer or Toyota authorized
repairer, or any reliable repairer.
If your vehicle overheats
When “EV System overheated
Output power reduced” is
shown on the multi-informa-
tion display, your vehicle may
be overheating.
NOTICE
■Cooling system coolant
The radiator coolant is exclusive for radiator usage. Damage may occur when water or any other type of cool-
ant is used, so never use any other fluid. When there is no “Toyota Genu-ine Traction Battery Coolant”, immedi-
ately contact any authorized Toyota retailer or Toyota authorized repairer, or any reliable repairer.
Correction procedures

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8-2. Steps to take in an emergency
5The coolant level is satisfactory
if it is between the “MAX” and
“MIN” lines on the reservoir.
Reservoir
“MAX” line
“MIN” line
6 If the coolant is insufficient,
replenish with “Toyota Genuine
Traction Battery Coolant”.
If you don’t have “Toyota Genuine Trac-
tion Battery Coolant”, contact any authorized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
1 Remove the bolt.
2 Open the reservoir cap.
Have the vehicle inspected at the
nearest authorized Toyota retailer
or Toyota authorized repairer, or
any reliable repairer as soon as
possible.
WARNING
■To prevent an accident or injury when inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
●If steam is seen coming from under the hood, do not open the hood
until the steam has subsided. The motor compartment may be very hot.
●Keep hands and clothing (espe-cially a tie, a scarf or a muffler)
away from the fan. Failure to do so may cause the hands or clothing to be caught, resulting in serious
injury.
●Do not loosen the coolant reservoir
cap while the EV system and radia- tor are hot. High temperature steam or coolant could spray out.
NOTICE
■When adding coolant
Add coolant slowly after the EV sys-
tem has cooled down sufficiently. Adding cool coolant to a hot EV sys-tem too quickly can cause damage to
the EV system.
■To prevent damage to the cooling
system
Observe the following precautions:
●Avoid contaminating the coolant
with foreign matter (such as sand or dust, etc.).
●Do not use water or any other cool-ant when refilling coolant. Also, do not use any additive agents for the
coolant.