2018 LEXUS LS500H coolant reservoir

3876-3. Do-it-yourself maintenance
LS500h_OM_OM50F42U_(U) 6
Maintenance and care
Engine oil level dipstick ( → P.388)
Power control unit coolant reservoir ( → P.390)
Engine coolant reservoir ( → P.390)
Engine oil filler cap ( → P.389)
Brake fluid reservoir ( → P.391)
Fuse boxes ( → P.414)
Washer fluid tank ( → P.392)
Engine coolant radiator ( → P.391)
Power control unit coolant radiator ( → P.391)
Electric cooling fan
Condenser ( → P.391)■
12-volt battery
→ P.393Engine compartment
Components
A
B
C
D
E
F
G
H
I
J
K

390 6-3. Do-it-yourself maintenance
LS500h_OM_OM50F42U_(U) with a heavy load, or when driving while
accelerating or decelerating frequently●
When leaving the engine idling for a long
time, or when driving frequently through
heavy traffic■
After changing the engine oil
The engine oil maintena nce data should be
reset. Perform the following procedures:
1 Press or of the meter control
switch to select .
2 Press or to select “Vehicle Set-
tings” and then press .
3 Press or to select “Oil Mainte-
nance” and then press .
4 Press or to select “Yes” and
then press .
A message will be displayed on the
multi-information disp lay when the reset
procedure has been completed.
The coolant level is satisfactory if it is
between the “F” and “L” lines on the
reservoir when the engine is cold. ■
Engine coolant reservoir
Reservoir cap
“F” line
“L” line If the level is on or below the “L” line, add
coolant up to the “F” line. ( → P.453)
■
Power control unit coolant reser-
voir
The coolant level is satisfactory if it is
between the “F” and “L” lines on the
reservoir when the hybrid system is WARNING■
Used engine oil●
Used engine oil contains potentially
harmful contaminants which may
cause skin disorders such as inflamma-
tion and skin cancer, so care should be
taken to avoid prolonged and
repeated contact. To remove used
engine oil from your skin, wash thor-
oughly with soap and water.
●
Dispose of used oil and filters only in a
safe and acceptable manner. Do not
dispose of used oil and filters in house-
hold trash, in sewers or onto the
ground.
Call your Lexus dealer, service station
or auto parts store for information
concerning recycling or disposal.
●
Do not leave used engine oil within the
reach of children. NOTICE■
To prevent serious engine damage
Check the oil level on a regular basis. ■
When replacing the engine oil ●
Be careful not to spill engine oil on the
vehicle components. ●
Avoid overfilling, or the engine could
be damaged. ●
Check the oil level on the dipstick
every time you re fill the vehicle.●
Be sure the engine o il filler cap is prop-
erly tightened.
Checking the coolant
A
B
C

3916-3. Do-it-yourself maintenance
LS500h_OM_OM50F42U_(U) 6
Maintenance and care cold.
Reservoir cap
“F” line
“L” lineIf the level is on or below the “L” line, add
coolant up to the “F” line. ( → P.453)
■
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 condition,
have your vehicle inspected by your
Lexus dealer.
■
Checking fluid level
The brake fluid level should be A
B
C WARNING■
When the hybrid system is hot
Do not remove the en gine/power control
unit coolant reservoir caps. ( → P.456)
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 neithe r 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
WARNING
■
When the hybrid system is hot
Do not touch the radiator or condenser
as they may be hot and cause serious
injuries, such as burns.
Checking and adding the brake
fluid

4537-2. Steps to take in an emergency
LS500h_OM_OM50F42U_(U) 7
When trouble arises 
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 radiator core (radiator) for any
leaks.
Radiators
Cooling fan If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
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.
( → P.455) Water can be used in an emergency if If your vehicle overheats The following may indicate that
your vehicle is overheating.
 The engine coolant temperature
gauge ( → P.77, 81) 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
Overheated Reduced Output
Power” is shown on the
multi-information display.
 Steam comes out from under the
hood.
Correction procedures A
B
A
B
C
D

454 7-2. Steps to take in an emergency
LS500h_OM_OM50F42U_(U) 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 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
Reduced Output Power” 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 (radiato r) for any leaks.
Radiator
Cooling fan If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
4 The coolant level is satisfactory if it
is between the “F” and “L” lines on
the reservoir.
Reservoir
“F” line
“L” line
5 Remove the engine compartment
cover and add coolant if necessary. Water can be used in an emergency if A
B
A
B
C

456 7-2. Steps to take in an emergency
LS500h_OM_OM50F42U_(U) 6 Add coolant through the inlet of the cap
until it is full, and then replace the
cap .
WARNING■
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 engine com-
partment may be very hot.●
After the hybrid system has been
turned off, check that the indicator on
the power switch and 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 cl othing (especially a
tie, a scarf or a muffler) getting caught,
resulting in serious injury.●
Do not loosen the coolant inlet cap or
the coolant reservoir cap while the
hybrid system and radiator are hot.
High temperature steam or coolant
could spray out.
NOTICE
■
When 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. B
B NOTICE■
To prevent damage to the cooling sys-
tem
Observe the following precautions: ●
Avoid contaminating the coolant with
foreign matter (such as sand or dust
etc.). ●
Do not use any coolant additive.