ECU Lexus ES300h 2020 Workshop Manual

3045-6. Using the other interior features
If there is not enough space to drive in a
circle, drive around the block until a direc-
tion is displayed.
WARNING
■When doing the circling calibration
Secure a wide space, and watch out for
people and vehicles in the vicinity. Do not
violate any local traffic rules while per-
forming circling calibration.

3146-2. Maintenance
Radiator/con-
denser
The radiator and con-
denser should be free
from foreign objects.
( P.324)
Washer fluid
Is there sufficient
washer fluid?
( P.325)
Trunk
ItemsCheck points
12-volt battery
Check the battery fluid
level and connections.
( P.326)
Vehicle interior
ItemsCheck points
Accelerator
pedal
• The accelerator
pedal should move
smoothly (without
uneven pedal effort
or catching).
Hybrid transmis-
sion “Park” mech-
anism
•When parked on a slope and the shift
lever is in P, is the
vehicle securely
stopped?
Brake pedal
•Does the brake pedal move
smoothly?
•Does the brake pedal have appro-
priate clearance
from the floor?
•Does the brake pedal have the cor-
rect amount of free
play?
ItemsCheck points
Brakes
•The vehicle should not pull to one side
when the brakes are
applied.
• The brakes should work effectively.
• The brake pedal should not feel
spongy.
• The brake pedal should not get too
close to the floor
when the brakes are
applied.
Head restraints
•Do the head restraints move
smoothly and lock
securely?
Indicators/buzz-
ers•Do the indicators and buzzers function
properly?
Lights
• Do all the lights come on?
• Are the headlights aimed correctly?
Parking brake
• Does the parking brake operate nor-
mally?
• When parked on a slope and the park-
ing brake is on, is the
vehicle securely
stopped?
Seat belts
• Do the seat belts operate smoothly?
• The seat belts should not be damaged.
ItemsCheck points

3496-3. Do-it-yourself maintenance
6
Maintenance and care
Normal fuse
Blown fuse
Type BNormal fuse
Blown fuse
Type CNormal fuse
Blown fuse
■After a fuse is replaced
●When installing the lid, make sure that the
tab is installed securely.
●If the lights do not turn on even after the
fuse has been replaced, a bulb may need
replacement. ( P.351)
●If the replaced fuse blows again, have the
vehicle inspected by your Lexus dealer.
■If there is an overload in a circuit
The fuses are designed to blow, protecting
the wiring harness from damage.
■When replacing light bulbs
Lexus recommends that you use genuine
Lexus products designed for this vehicle.
Because certain bulbs are connected to cir-
cuits designed to prevent overload, non-
genuine parts or parts not designed for this
vehicle may be unusable.A
B
A
B
A
B
WARNING
■To prevent system breakdowns and
vehicle fire
Observe the following precautions.
Failure to do so may cause damage to
the vehicle, and possibly a fire or injury.
●Never use a fuse of a higher amperage
rating than that indicated, or use any
other object in place of a fuse.
●Always use a genuine Lexus fuse or
equivalent.
Never replace a fuse with a wire, even
as a temporary fix.
●Do not modify the fuses or fuse boxes.
NOTICE
■Before replacing fuses
Have the cause of electrical overload
determined and repaired by your Lexus
dealer as soon as possible.

3546-3. Do-it-yourself maintenance
bumper.
8Engage the clips to the front
bumper to install the fender liner,
and then remove the protective
tape.
WARNING
■Replacing light bulb
●Turn off the light. Do not attempt to
replace the bulb immediately after
turning off the light.
The bulb become very hot and may
cause burns.
●Do not touch the glass portion of the
light bulb with bare hands. When it is
unavoidable to hold the glass portion,
use and hold with a clean dry cloth to
avoid getting moisture and oils on the
bulb.
Also, if the bulb is scratched or
dropped, it may blow out or crack.
●Fully install light bulb and any parts
used to secure it. Failure to do so may
result in heat damage, fire, or water
entering the light unit. This may dam-
age the light or cause condensation to
build up on the lens.
■To prevent damage or fire
●Make sure bulb is fully seated and
locked.
●Check the wattage of the bulb before
installing to prevent heat damage.

3567-1. Essential information
7-1.Essential information
Press the switch to flash all of the turn
signal lights.
To turn them off, press the switch once
again.
■Emergency flashers
●If the emergency flashers are used for a
long time while the hybrid system is not
operating (while the “READY” indicator
is not illuminated), the 12-volt battery may
discharge.
●If any of the SRS airbags deploy (inflate)
or in the event of a strong rear impact, the
emergency flashers will turn on automati-
cally.
The emergency flashers will turn off auto-
matically after operating for approxi-
mately 20 minutes. To manually turn the
emergency flashers off, press the switch
twice.
(The emergency flashers may not turn on
automatically dependin g on the force of
the impact and conditions of the colli-
sion.)
1 Steadily step on the brake pedal
with both feet and firmly depress it.
Do not pump the brake pedal repeatedly
as this will increase the effort required to
slow the vehicle.
2Shift the shift lever to N.
If the shift lever is shifted to N
3 After slowing down, stop the vehi-
cle in a safe place by the road.
4 Stop the hybrid system.
If the shift lever cannot be shifted to
N
3 Keep depressing the brake pedal
with both feet to reduce vehicle
speed as much as possible.
4 To stop the hybrid system, press
and hold the power switch for 2
consecutive seconds or more, or
Emergency flashers
The emergency flashers are used to
warn other drivers when the vehicle
has to be stopped in the road due to
a breakdown, etc.
Operating instructions
If your vehicle has to be
stopped in an emergency
Only in an emergency, such as if it
becomes impossible to stop the
vehicle in the normal way, stop the
vehicle using the following proce-
dure:
Stopping the vehicle

3597-2. Steps to take in an emergency
7
When trouble arises
7-2.Steps to take in an emergency
The following may indicate a problem
with your hybrid transmission. Contact
your Lexus dealer or commercial tow-
ing service before towing.
If your vehicle needs to be
t
owed
If towing is ne cessary, we recom-
mend having your vehicle towed by
your Lexus dealer or commercial
towing service, using a wheel-lift
type truck or flatbed truck.
Use a safety chain system for all
towing, and abide by all state/pro-
vincial and local laws.
WARNING
Observe the following precautions.
Failure to do so may result in death or
serious injury.
■When towing the vehicle
Be sure to transport the vehicle with the
front wheels raised or with all four wheels
raised off the ground. If the vehicle is
towed with the front wheels contacting
the ground, the drivetrain and related
parts may be damaged or electricity
generated by the operation of the motor
may cause a fire to occur depending on
the nature of the damage or malfunction.
■While towing (vehicles with a towing
eyelet)
●When towing using cables or chains,
avoid sudden starts, etc. which place
excessive stress on the towing eyelets,
cables or chains. The towing eyelets,
cables or chains may become dam-
aged, broken debris may hit people,
and cause serious damage.
●Do not turn the power switch off.
There is a possibility that the steering
wheel is locked and cannot be oper-
ated.
■Installing towing eyelets to the vehi-
cle (vehicles with a towing eyelet)
Make sure that towing eyelets are
installed securely.
If not securely installed, towing eyelets
may come loose during towing.
NOTICE
■To prevent damage to the vehicle
when towing using a wheel-lift type
truck
●Do not tow the vehicle from the rear
when the power switch is off. The
steering lock mechanism is not strong
enough to hold the front wheels
straight.
●When raising the vehicle, ensure ade-
quate ground clearance for towing at
the opposite end of the raised vehicle.
Without adequate clearance, the vehi-
cle could be damaged while being
towed.
■To prevent damage to the vehicle
when towing with a sling-type truck
Do not tow with a sling-type truck, either
from the front or rear.
■To prevent damage to the vehicle
during emergency towing (vehicles
with a towing eyelet)
Do not secure cables or chains to the
suspension components.
Situations when it is necessary to
contact dealers before towing

3617-2. Steps to take in an emergency
7
When trouble arises
If a tow truck is not available in an
emergency, your vehicle may be tem-
porarily towed using cables or chains
secured to the emergency towing eye-
lets. This should only be attempted on
hard surfaced roads for short distances
at under 18 mph (30 km/h).
A driver must be in the vehicle to steer
and operate the brakes. The vehicle’s
wheels, drive train, axles, steering and
brakes must be in good condition.
To have your vehicle towed by another
vehicle, the towing eyelet must be
installed to your vehicle. Install the tow-
ing eyelet using the following proce-
dure.
1 Take out the towing eyelet.
(P.379)
2 Remove the eyelet cover using a
flathead screwdriver.
To protect the bodywork, place a rag
between the screwdriver and the vehicle
body as shown in the illustration.
3Insert the towing eyelet into the
hole and tighten partially by hand.
4 Tighten down the towing eyelet
securely using a wheel nut wrench
or hard metal bar.
5 Securely attach cables or chains to
the towing eyelet.
Take care not to damage the vehicle body.
6Enter the vehicle being towed and
start the hybrid system.
If the hybrid system does not start, turn the
power switch to ON mode.
7Shift the shift lever to N and release
the parking brake.
When the shift lever cannot be shifted:
P.151
■While towing
If the hybrid system is off, the power assist
for the brakes and steer ing will not function,
making steering and braking more difficult.
■Wheel nut wrench
Wheel nut wrench is installed in trunk.
Emergency towing (vehicles
with a towing eyelet)
Emergency towing procedure
(vehicles with a towing eyelet)

3717-2. Steps to take in an emergency
7
When trouble arises
■Brake hold operated indicator (warning buzzer)
■Hybrid system overheat warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
■Master warning light (warning buzzer)
■Warning buzzer
In some cases, the bu zzer may not be heard
due to being in a noisy location or audio
sound.
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause th e warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■SRS warning light
This warning light system monitors the air-
bag sensor assembly, fr ont impact sensors,
side impact sensors (front door), side
impact sensors (front), side impact sensors
(rear), driver’s seat position sensor, driver’s
seat belt buckle switch, front passenger
occupant classification system (ECU and
sensors), “AIR BAG ON” indicator light, “AIR BAG OFF” indicator light, front pas-
senger’s seat belt buckle switch, seat belt
pretensioners, airbags, interconnecting wir-
ing and power sources. (
P.28)
■Electric power steering system warning
light (warning buzzer)
When the 12-volt battery charge becomes
insufficient or the voltage temporarily
drops, the electric power steering system
warning light may come on and the warning
buzzer may sound.
■When the tire pressure warning light
comes on
Inspect the tires to check if a tire is punc-
tured.
If a tire is punctured:  P.378
If none of the tires are punctured:
Turn the power switch off then turn it to ON
mode. Check if the tire pressure warning
light comes on or blinks.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
Indicates that the hybrid system has overheated
Stop the vehicle in a safe place. Handling method ( P.396)
Warning lightDetails/Actions
A buzzer sounds and the warning light comes on and flashes to indicate
that the master warning system has detected a malfunction.
 P.374

3817-2. Steps to take in an emergency
7
When trouble arises
3The lever can be hooked on the
edge of the trunk.
4
Remove the jack.
1
Remove the auxiliary box. 2
Loosen the center fastener that
secures the spare tire.
1
Chock the tires.
NOTICE
■To prevent damage to luggage mat
When closing the trunk door, do not
leave the luggage mat lever hooked on
the edge of the trunk.
Taking out the spare tire
WARNING
■When storing the spare tire
Be careful not to catch fingers or other
body parts between the spare tire and
the body of the vehicle.
Replacing a flat tire
Flat tireWheel chock positions
Front left-
hand sideBehind the rear right-hand
side tire
Front right-
hand sideBehind the rear left-hand
side tire
Rear left-hand
sideIn front of the front right-
hand side tire
Rear right-
hand sideIn front of the front left-
hand side tire

3857-2. Steps to take in an emergency
7
When trouble arises
One of the following may be the cause
of the problem:
The electronic key may not be func-
tioning properly. ( P.389)
 There may not be sufficient fuel in
the vehicle’s tank.
Refuel the vehicle. ( P.170)
 There may be a malfunction in the
immobilizer system. ( P.67)
 There may be a malfunction in the
steering lock system.
 The hybrid system may be malfunc-
tioning due to an electrical problem
such as electronic key battery
depletion or a blown fuse. However,
depending on the type of malfunc-
tion, an interim measure is available
to start the hybrid system.
One of the following may be the cause
WARNING
■Speed limit when using the compact
spare tire
Do not drive at speeds in excess of 50
mph (80 km/h) when a compact spare
tire is installed on the vehicle.
The compact spare tire is not designed
for driving at high speeds. Failure to
observe this precaution may lead to an
accident causing deat h or serious injury.
■After using the tools and jack
Before driving, make sure all the tools
and jack are securely in place in their
storage location to reduce the possibility
of personal injury during a collision or
sudden braking.
NOTICE
■Be careful when driving over bumps
with the compact spare tire installed
on the vehicle
The vehicle becomes lower when driving
with the compact spare tire compared to
when driving with standard tires. Be
careful when driving over uneven road
surfaces.
■Driving with tire chains and the com-
pact spare tire
Do not fit tire chains to the compact
spare tire.
Tire chains may damage the vehicle body
and adversely affect driving perfor-
mance.
■When replacing the tires
When removing or fitting the wheels,
tires or the tire pressure warning valve
and transmitter, contact your Lexus
dealer as the tire pr essure warning valve
and transmitter may be damaged if not
handled correctly.
If the hybrid system will not
s
tart
Reasons for the hybrid system not
starting vary depending on the situ-
ation. Check the following and per-
form the appropriate procedure:
The hybrid system will not start
even though the correct starting
procedure is being followed.
(  P.143)
The interior lights and head-
lights are dim, or the horn does
not sound or sounds at a low vol-
ume.