2019 Lexus ES300h cooling

3046-1. Maintenance and care
To prevent the hybrid battery (traction
battery) air intake vent from becoming
clogged, clean it periodically.
■Cleaning the air intake vent
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 a compressed air
blow gun, etc. may push it into the air intake
vent. ( P.307)
If dust and clogs cannot be completely
removed with the air intake vent cover
installed, remove the cover and clean the
filter.
■Cleaning the filter
If “Maintenance required for Traction
battery cooling parts See owner’s man-
ual” is displayed on the multi-informa-
NOTICE
■Preventing damage to leather sur-
faces
Observe the following precautions to
avoid damage to and deterioration of
leather surfaces:
●Remove any dust or dirt from leather
surfaces immediately.
●Do not expose the vehicle to direct
sunlight for extended periods of time.
Park the vehicle in the shade, espe-
cially during summer.
●Do not place items made of vinyl, plas-
tic, or containing wax on the uphol-
stery, as they may stick to the leather
surface if the vehicle interior heats up
significantly.
■Water on the floor
Do not wash the vehicle floor with water.
Vehicle systems such as the audio system
may be damaged if water comes into
contact with electrical components such
as the audio system above or under the
floor of the vehicle. Water may also
cause the body to rust.
■When cleaning the inside of the wind-
shield
Do not allow glass cleaner to contact the
lens. Also, do not touch the lens.
(  P.163)
■Cleaning the inside of the rear win-
dow
●Do not use glass cleaner to clean the
rear window, as this may cause dam-
age to the rear window defogger
heater wires or antenna. Use a cloth
dampened with lukewarm water to
gently wipe the window clean. Wipe
the window in strokes running parallel
to the heater wires or antenna.
●Be careful not to scratch or damage
the heater wires or antenna.
Cleaning the hybrid battery
(traction battery) air intake vent

3076-1. Maintenance and care
6
Maintenance and care
■If “Maintenance required for Traction
battery cooling parts See owner’s man-
ual” is displayed on the multi-informa-
tion display
●If this warning message is displayed on
the multi-information display, remove the
air intake vent cover and clean the filter.
●After 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
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.
 Remove dirt using a water-damp-
ened soft cloth or synthetic chamois.
 Wipe the surface with a dry soft
cloth to remove any remaining
moisture.
WARNING
■When cleaning the hybrid battery
(traction battery) air intake vent/fil-
ter
●Do not use water or other liquids to
clean the air intake vent/filter. If water
is applied to the hybrid battery (trac-
tion battery) or other components, a
malfunction or fire may occur.
●When the air intake vent cover (under
the right side of the rear seat) is to be
removed, make sure to turn the power
switch off to stop the hybrid system.
■When removing the air intake vent
cover
Do not touch the service plug located
near the air intake vent. (P.57)
NOTICE
■When cleaning the air intake vent
Observe the following precautions. Fail-
ure to do so may cause damage to the
vehicle.
●When cleaning the air intake vent,
make sure to only use a vacuum to
suck out dust and clogs. If a com-
pressed air blow gun, etc. is used to
blow out dust and clogs, the dust or
clogs may be pushed into the air intake
vent.
●Do not allow water or foreign matter to
enter the air intake vent when the
cover is removed.
●Carefully handle the removed filter so
that it will not to damage.
If the filter is damaged, have it replaced
with a new filter by your Lexus dealer.
●Make sure to reinstall the filter and
cover to its original positions after
cleaning.
●Do not install anything to the air intake
vent other than the exclusive filter for
this vehicle or use the vehicle without
the filter installed.
●Do not drive continuously with the
message “Maintenance Required for
Traction Battery Cooling Parts See
Owner’s Manual” displayed. If the
warning message is displayed, clean
the air intake vent immediately.
Cleaning the areas with satin-fin-
ish metal accents

3156-3. Do-it-yourself maintenance
6
Maintenance and care
Radiator and
condenser
( P.321)

Tire inflation
pressure
( P.334)• Tire pressure gauge
• Compressed air source
Washer fluid
( P.322)
• Water or washer fluid
containing antifreeze
(for winter use)
• Funnel (used only for adding water or washer
fluid)
WARNING
The engine compartment contains many
mechanisms and fluids that may move
suddenly, become hot, or become elec-
trically energized. To avoid death or seri-
ous injury, observe the following
precautions.
■When working on the engine com-
partment
●Make sure that the “IGNITION ON”
on the multi-information display and
the “READY” indicator are both off.
●Keep hands, clothi ng and tools away
from the moving fan and engine drive
belt.
●Be careful not to touch the engine,
power control unit, radiator, exhaust
manifold, etc. right after driving as they
may be hot. Oil and other fluids may
also be hot.
●Do not leave anything that may burn
easily, such as paper and rags, in the
engine compartment.
●Do not smoke, cause sparks or expose
an open flame to fuel. Fuel fumes are
flammable.
ItemsParts and tools■When working near the electric cool-
ing fan or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the
electric cooling fan may automatically
start to run if the air conditioning is on
and/or the coolant temperature is high.
(  P.321)
■Safety glasses
Wear safety glasses to prevent flying or
falling material, fluid spray, etc. from get-
ting in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter
removed may cause excessive engine
wear due to dirt in the air.

3186-3. Do-it-yourself maintenance
Fuse boxes (P.341)
Engine oil filler cap ( P.319)
Engine oil level dipstick ( P.318)
Brake fluid reservoir ( P.322)
Radiator ( P.321)
Electric cooling fan
Condenser ( P.321)
Power control unit coolant reservoir ( P.321)
Engine coolant reservoir ( P.320)
Washer fluid tank ( P.322)
■12-volt battery
 P.323
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

3216-3. Do-it-yourself maintenance
6
Maintenance and care
Reservoir cap
“F” line
“L” line
If the level is on or below the “L” line, add
coolant up to the “F” line. ( P.388)
■Power 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.389)
■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 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.
■If the coolant level drops within a short
time of replenishing
Visually check the radiator, hoses,
engine/power control unit coolant reservoir
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
■When the hybrid system is hot
Do not remove the en gine/power control
unit coolant reservoir caps or the radia-
tor cap. ( P.391)
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
■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 pre-
vent it from damaging parts or paint.
Checking the radiator and con-
denser

3717-2. Steps to take in an emergency
7
When trouble arises
schedule* should be performed soon.
Comes on approximately 4500 miles
(7200 km) after the message has been
reset. If necessary, perform maintenance.
Please reset the message after the mainte-
nance is performed. ( P.309)
*: Refer to the separa te “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the maintenance interval
applicable to your vehicle.
■If “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 ha s been reset.) Per-
form the necessary maintenance. Please
reset the message after the maintenance is
performed. ( P.309)
*: Refer to the separa te “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the maintenance interval
applicable to your vehicle.
■If “Oil Maintenance Required Soon” is
displayed
Indicates that the engine oil should be
scheduled to be changed.
Check the engine oil and change it if neces-
sary. After changing the engine oil, make
sure to reset the message. ( P.309)
■If “Oil Maintenance Required” is dis-
played
Indicates that the engine oil should be
changed.
Check and change the en gine oil, and oil fil-
ter by your Lexus deal er. After changing the
engine oil, make sure to reset the message.
(  P.320)
■If a message that in dicates 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.
■If a message that indicates the need for
referring to Owner’
s Manual is dis-
played
●If any of the following messages are
shown on the multi-information display,
follow the instructions.
• “Engine Coolant Temp High” ( P.388)
●If any of the following messages are
shown on the multi-info rmation display, it
may indicate a malf unction. 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”
●If any of the following messages are
shown on the multi-info rmation display, it
may indicate a malfun ction. Immediately
stop the vehicle and contact your Lexus
dealer.
• “Braking Power Low”
• “Charging System Malfunction”
• “Oil Pressure Low”
• “Hybrid system stopped”
• “Engine stopped”
●If “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.384).
*: Displays for about 6 seconds
●If “Maintenance required for Traction bat-
tery cooling Parts” is shown, the filters
may be clogged, the air intake vents may
be blocked, or there may be a gap in the
duct. Therefore, perform the following
correction procedure.
• If the air intake vent s and filters of the
hybrid battery (traction battery) are dirty,
perform the procedure on P.304 to

3887-2. 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.
WARNING
■When exchanging the 12-volt battery
●When the vent plug and indicator are
close to the hold down clamp, the bat-
tery fluid (sulfuric acid) may leak.
●After exchanging, securely attach the
exhaust hose and exhaust hole plug to
the exhaust hole of the exchanged 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
■When handling jumper cables
When connecting the jumper cables,
ensure that they do not become entan-
gled in the cooling fan or engine drive
belt.
■To 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.
If your vehicle overheats
The following may indicate that
your vehicle is overheating.
 The engine coolant temperature
gauge ( P.70) is in the red zone
or a loss of hybrid system power is
experienced. (For example, 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

3897-2. Steps to take in an emergency
7
When trouble arises
3After the hybrid system has cooled
down sufficiently, inspect the hoses
and cooling system for 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 “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.
6
Start 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 oper ate 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.
A
B
A
B
C
D