cooling LEXUS ES300h 2022 User Guide

3236-3. Do-it-yourself maintenance
6
Maintenance and care
Fuse boxes (P.349)
Engine oil filler cap ( P.324)
Engine oil level dipstick ( P.323)
Brake fluid reservoir ( P.327)
Radiator ( P.326)
Electric cooling fan
Condenser ( P.326)
Power control unit coolant reservoir ( P.326)
Engine coolant reservoir ( P.325)
Washer fluid tank ( P.327)
Q12-volt battery
 P.328
With the engine at operating tempera-
ture and turned off, check the oil level
Engine compartment
Components
A
B
C
D
E
F
G
H
I
J
Checking and adding the engine
oil

3266-3. Do-it-yourself maintenance
Reservoir cap
“F” line
“L” line
If the level is on or below the “L” line, add
coolant up to the “F” line. (P.396)
QPower control unit coolant reser-
voir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW” line,
add coolant up to the “FULL” line.
(  P.397)
QCoolant 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 mix-
ture of 50% coolant and 50% deionized
water. (Minimum temperature: -31°F [-
35°C])
Canada:
“Toyota Super Long Life Coolant” is a mix-
ture of 55% coolant and 45% deionized
water. (Minimum temperature: -44°F [-
42°C])
For more details about coolant, contact
your Lexus dealer.
QIf the coolant level drops within a short
time of replenishing
Visually check the radiator, hoses,
engine/power control unit coolant reser-
voir caps, drain cock and water pump.
If you cannot find a leak, have your Lexus
dealer 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 condi-
tion, have your vehicle inspected by
your Lexus dealer.
A
B
C
A
B
C
WARNING
QWhen the hybrid system is hot
Do not remove the engine/power con-
trol unit coolant reservoir caps or the
radiator cap. ( P.398)
The cooling system may be under pres-
sure and may spray hot coolant if the cap
is removed, causing serious injuries, such
as burns.
NOTICE
QWhen 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.
QIf you spill coolant
Be sure to wash it off with water to pre-
vent it from damaging parts or paint.
Checking the radiator and con-
denser

3436-3. Do-it-yourself maintenance
6
Maintenance and care
filter.
Remove the dust from the air intake
vent with a vacuum cleaner, etc.
Make sure to only use a vacuum to suck
out dust and clogs. Attempting to blow out
dust and clogs using an airgun, etc. may
push it into the air intake vent. (P.346)
If dust and clogs cannot be completely
removed with the air intake vent cover
installed, remove the cover and clean
NOTICE
QWhen using the air conditioning sys-
tem
OMake sure that a filter is always
installed.
Using the air conditioning system with-
out a filter may cause damage to the
system.
OThe filter is replaceable.
When cleaning the filter, do not clean
with water or an air gun.
QTo prevent damage to the filter cover
When moving the filter cover in the
direction of arrow to release the fitting,
pay attention not to apply excessive
force to the claws. Otherwise, the claws
may be damaged.
Cleaning the hybrid battery
(traction battery) air intake
vent and filter
To prevent the fuel economy from
being affected, visually inspect the
hybrid battery (traction battery) air
intake vent periodically for dust and
clogs. If it is dusty or clogged or if
“Maintenance required for Trac-
tion battery cooling parts See
owner’s manual” is displayed on the
multi-information display, clean the
air intake vent using the following
procedures:
Cleaning the air intake vent
If dust and clogs cannot be com-
pletely removed

3456-3. Do-it-yourself maintenance
6
Maintenance and care
6Reinstall the filter to the cover.
1 Engage the filter to the 2 claws as
shown in the illustration.
2 Engage the 3 claws to install the fil-
ter.
Make sure that the filter is not crooked or
deformed when installing it.
7Install the air intake vent cover.
1 Insert the tab of the cover as shown
in the illustration.
2 Push the cover to engage the 7
claws. 8
Using a Phillips screwdriver, install
the clip.
QScheduled maintenance of the air
intake vent is necessary when
In some situations such as when the vehicle
is used frequently or in heavy traffic or dusty
areas, the air intake vent may need to be
cleaned more regularly.
For details, refer to “Owner’s Manual Sup-
plement” or “Scheduled Maintenance”.
QCleaning the air intake vent
ODust in the air intake vent may interfere
with the cooling of the hybrid battery
(traction battery). If charging/discharg-
ing of the hybrid battery (traction battery)
becomes limited, the distance that the
vehicle can be driven using the electric
motor (traction motor) may be reduced
and the fuel economy may be reduced.
Inspect and clean the air intake vent peri-
odically.
OImproper handling of the air intake vent
cover and filter may re sult in damage to
them. If you have any concerns about
cleaning the filter, contact your Lexus
dealer.
QIf “Maintenance required for Traction
battery cooling parts See owner’s man-
ual” is displayed on the multi-informa-
tion display
OIf this warning message is displayed on
the multi-information display, remove the
air intake vent cover and clean the filter.
(  P.343)
OAfter cleaning the air intake vent, start
the hybrid system and check that the
warning message is no longer displayed.
After the hybrid system is started, it may

3466-3. Do-it-yourself maintenance
be necessary to drive the vehicle up to
approximately 20 minutes before the
warning message disappears. If the warn-
ing message does not disappear after
driving for appropriately 20 minutes,
have the vehicle inspected by your Lexus
dealer.
WARNING
QWhen cleaning the air intake vent
ODo not use water or other liquids to
clean the air intake vent. If water is
applied to the hybrid battery (traction
battery) or other components, a mal-
function or fire may occur.
OBefore cleaning the air intake vent,
make sure to turn the power switch off
to stop the hybrid system.
QWhen removing the air intake vent
cover
Do not touch the service plug located
near the air intake vent. ( P.63)
NOTICE
QWhen cleaning the air intake vent
When cleaning the air intake vent, make
sure to only use a vacuum to suck out
dust and clogs. If a compressed air blow
gun, etc. is used to blow out dust and
clogs, the dust or clogs may be pushed
into the air intake vent, which may affect
the performance of the hybrid battery
(traction battery) and cause a malfunc-
tion.
QTo prevent damage to the vehicle
ODo not allow water or foreign matter
to enter the air intake vent when the
cover is removed.
OCarefully handle the removed filter so
that it will not be damage.
If the filter is damaged, have it
replaced with a new filter by your
Lexus dealer.
OMake sure to reinstall the filter and
cover to their original positions after
cleaning.
ODo not install anything to the air intake
vent other than the exclusive filter for
this vehicle or use the vehicle without
the filter installed.
QIf “Maintenance required for Trac-
tion battery cooling parts See
owner’s manual” is displayed on the
multi-information display
If the vehicle is continuously driven with
the warning message (indicating that
charging/discharging of the hybrid bat-
tery (traction battery) may become lim-
ited) displayed, the hybrid battery
(traction battery) may malfunction.

3787-2. Steps to take in an emergency
ment” for the maintenance interval
applicable to your vehicle.
QIf “Maintenance Required Visit Your
Dealer” is displayed
Indicates that all maintenance is required to
correspond to the driven distance on the
maintenance schedule
*.
Comes on approximately 5000 miles
(8000 km) after the message has been
reset. (The indicator will not work properly
unless the message has been reset.) Per-
form the necessary maintenance. Please
reset the message after the maintenance is
performed. ( P.314)
*: Refer to the separate “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the maintenance interval
applicable to your vehicle.
QIf “Oil Maintenance Required Soon” is
displayed
Indicates that the engine oil should be
scheduled to be changed.
Check the engine oil an d change it if neces-
sary. After changing the engine oil, make
sure to reset the message. ( P.314)
QIf “Oil Maintenance Required” is dis-
played
Indicates that the engine oil should be
changed.
Check and change the engine oil, and oil fil-
ter by your Lexus dealer. After changing
the engine oil, make sure to reset the mes-
sage. ( P.325)
QIf a message that indicates the need for
visiting your Lexus dealer is displayed
The system or part shown on the multi-
information display is malfunctioning. Have
the vehicle inspected by your Lexus dealer
immediately.
QIf a message that indicates the need for
referring to Owner’s Manual is dis-
played
OIf any of the following messages are
shown on the multi-information display,
follow the instructions.
• “Engine Coolant Temp High” ( P.396)
OIf any of the following messages are
shown on the multi-information display, it
may indicate a malfunction. Have the
vehicle inspected by your Lexus dealer
immediately.
• “Access System with Elec. Key Malfunc-
tion”
• “Hybrid system malfunction”
•“Check Engine”
• “Hybrid battery system malfunction”
• “Accelerator system malfunction”
OIf any of the following messages are
shown on the multi-information display, it
may indicate a malfunction. Immediately
stop the vehicle and contact your Lexus
dealer.
•“Braking Power Low”
• “Charging System Malfunction”
• “Oil Pressure Low”
OIf any of the following messages are
shown on the multi-information 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. ( P.62)
• “Hybrid system stopped”
• “Engine stopped”
OIf “Low Auxiliary Battery” is shown
• When the display goes off after several
seconds
*:
Maintain the hybrid system operation 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 proce-
dures for “If the 12-volt battery is dis-
charged” ( P.391).
*: Displays for about 6 seconds
OIf “Maintenance required for Traction
battery cooling parts” is shown, the filter
may be clogged, the air intake vent may
be blocked, or there may be a gap in the
duct. Therefore, perform the following
correction procedure.
• If the air intake vent and filter of the
hybrid battery (traction battery) are dirty,
perform the procedure on P.343 to
clean them.
• If the warning message is shown when the air intake vent and filter of the hybrid

3957-2. Steps to take in an emergency
7
When trouble arises
WARNING
OIn the event that 12-volt battery fluid
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.
OAlways wash your hands after han-
dling the 12-volt battery support, ter-
minals, and other battery-related
parts.
ODo not allow children near the 12-volt
battery.
QAfter recharging the 12-volt battery
Have the 12-volt battery inspected at
your Lexus dealer as soon as possible. If
the 12-volt battery is deteriorating, con-
tinued use may cause the 12-volt battery
to emit a malodorous gas, which may be
detrimental to the health of passengers.
QWhen disconnecting the 12-volt bat-
tery
Do not disconnect the negative (-) termi-
nal on the body side. The disconnected
negative (-) terminal may touch the posi-
tive (+) terminal, which may cause a short
and result in death or serious injury.
QWhen exchanging the 12-volt battery
OWhen the vent plug and indicator are
close to the hold down clamp, the bat-
tery fluid (sulfuric acid) may leak.
OAfter replacing, securely attach the
exhaust hose and exhaust hole plug to
the exhaust hole of the replaced 12-
volt battery. If not properly installed,
gases (hydrogen) may leak into the
vehicle interior, and there is the possi-
ble danger of the gas igniting and
exploding.
NOTICE
QWhen handling jumper cables
When connecting the jumper cables,
ensure that they do not become entan-
gled in the cooling fan or engine drive
belt.
QTo prevent damaging the vehicle
The exclusive jump starting terminal is to
be used when charging the 12-volt bat-
tery from another vehicle in an emer-
gency. It cannot be used to jump start
another vehicle.

3967-2. Steps to take in an emergency
If the engine coolant temperature
gauge enters the red zone or
“Engine Coolant Temp High Stop in
a Safe Place See Owner’s Manual”
is shown on the multi-information
display
1 Stop the vehicle in a safe place and
turn off the air conditioning system,
and then stop the hybrid system.
2 If you see steam:
Carefully lift the hood after the
steam subsides.
If you do not see steam:
Carefully lift the hood.
3 After the hybrid system has cooled
down sufficiently, inspect the hoses
and cooling system for leaks.
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
Radiator
Cooling fan
4 The coolant level is satisfactory if it
is between the “F” and “L” lines on
the reservoir.
Reservoir
“F” line
“L” line
Coolant inlet cap
5 Add coolant if necessary.
Water can be used in an emergency if
engine coolant is unavailable.
If water was added in an emergency, have
the vehicle inspected at your Lexus dealer
If your vehi cle overheats
The following may indicate that
your vehicle is overheating.
The engine coolant temperature
gauge ( P.76, 80) is in the red
zone or a loss of hybrid system
power is experienced. (For exam-
ple, the vehicle speed does not
increase.)
 “Engine Coolant Temp High Stop
in a Safe Place See Owner’s
Manual” or “Hybrid system over-
heated Output power reduced” is
shown on the multi-information
display.
 Steam comes out from under the
hood.
Correction procedures
A
B
A
B
C
D

3977-2. Steps to take in an emergency
7
When trouble arises
as soon as possible.
6Start the hybrid system and turn the
air conditioning system on to check
that the radiator cooling fan oper-
ates and to check for coolant leaks
from the radiator or hoses.
The fan operates when the air conditioning
system is turned on immediately after a
cold start. Confirm that the fan is operating
by checking the fan sound and air flow. If it
is difficult to check these, turn the air con-
ditioning system on and off repeatedly.
(The fan may not operate in freezing tem-
peratures.)
7 If the fan is not operating:
Stop the hybrid system immediately
and contact your Lexus dealer.
If the fan is operating:
Have the vehicle inspected at the
nearest Lexus dealer.
If “Hybrid system overheated Out-
put power reduced” is shown on the
multi-information display
1 Stop the vehicle in a safe place.
2 Stop the hybrid system and care-
fully lift the hood. 3
After the hybrid system has cooled
down, inspect the hoses and radia-
tor core (radiator) for any leaks.
Radiator
Cooling fan
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
4The coolant level is satisfactory if it
is between the “FULL” and “LOW”
lines on the reservoir.
Reservoir
“FULL” line
“LOW” line
5 Add coolant if necessary.
Water can be used in an emergency if
power control unit coolant is unavailable.
If water was added in an emergency, have
the vehicle inspected at your Lexus dealer
A
B
A
B
C

3987-2. Steps to take in an emergency
as soon as possible.
6After stopping the hybrid system
and waiting for 5 minutes or more,
start the hybrid system again and
check if “Hybrid system over-
heated Output power reduced” is
shown on the multi-information dis-
play.
If the message does not disappear:
Stop the hybrid system and contact your
Lexus dealer.
If the message is not displayed:
The hybrid system temperature has
dropped and the vehicle may be driven
normally.
However, if the message appears again
frequently, contact your Lexus dealer.
WARNING
QWhen inspecting under the hood of
your vehicle
Observe the following precautions.
Failure to do so may result in serious
injury such as burns.
OIf steam is seen coming from under the
hood, do not open the hood until the
steam has subsided. The engine com-
partment may be very hot.
OAfter the hybrid system has been
turned off, check that the “READY”
indicator are off.
When the hybrid system is operating,
the gasoline engine may automatically
start, or the cooling fan may suddenly
operate even if the gasoline engine
stops. Do not touch or approach rotat-
ing parts such as the fan, which may
lead to fingers or clothing (especially a
tie, a scarf or a muffler) getting caught,
resulting in serious injury.
ODo not loosen the coolant inlet cap or
coolant reservoir caps while the hybrid
system and radiator are hot.
High temperature steam or coolant
could spray out.
NOTICE
QWhen adding engine/power control
unit coolant
Add coolant slowly after the hybrid sys-
tem has cooled down sufficiently. Adding
cool coolant to a hot hybrid system too
quickly can cause damage to the hybrid
system.
QTo prevent damage to the cooling
system
Observe the following precautions:
OAvoid contaminating the coolant with
foreign matter (such as sand or dust
etc.).
ODo not use any coolant additive.