ECU LEXUS IS300 2021 Workshop Manual

2886-2. Maintenance
Radiator, con-
denser and inter-
cooler radiatorThe radiator and con-
denser should be free
from foreign objects.
( P.300)
Washer fluid
Is there sufficient
washer fluid?
( P.302)
Vehicle interior
ItemsCheck points
Accelerator
pedal
• The accelerator
pedal should move
smoothly (without
uneven pedal effort
or catching).
Automatic trans-
mission “Park”
mechanism
•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?
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

3256-3. Do-it-yourself maintenance
6
Maintenance and care
by inserting it and turning it clock-
wise.
9 Install the light unit.
Align the tabs and push the light unit
toward the front of the vehicle to install it.
10Install the 2 bolts. 11
Install the cover.
12 Remove the protective tape.
■When replacing the front turn signal
lights (bulb type)
When the washer fluid filler opening is
removed with a large amount of washer
fluid contained in the washer tank, washer
fluid may spill onto the vehicle and cleaning
may be required.
WARNING
■Replacing light bulbs
●Turn off the lights. Do not attempt to
replace the bulb immediately after
turning off the lights.
The bulbs 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 bulbs and any parts
used to secure them. Failure to do so
may result in heat damage, fire, or
water entering the he adlight unit. This
may damage the headlights or cause
condensation to build up on the lens.
■To prevent damage or fire
●Make sure bulbs are fully seated and
locked.

3287-1. 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 engine is not operat-
ing, the 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 depending 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 engine.
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 engine, press and hold
the engine switch for 2 consecutive
Emergency flashers
The emergency flashers are used to
warn other drivers when the vehicle
has to be stopped on 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

3327-2. Steps to take in an emergency
The following may indicate a problem
with the drivetrain. Contact your Lexus
dealer or commercial towing service
before towing.
 The engine is running but the vehi-
cle does not move.
 The vehicle makes an abnormal
sound.
From the front
Use a towing dolly under the rear
wheels.
WARNING
■While towing
●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 engine switch off.
There is a possibility that the steering
wheel is locked and cannot be oper-
ated.
■Installing towing eyelet to the vehicle
Make sure that towing eyelet is installed
securely.
If not securely installed, towing eyelet
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 engine 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
Do not secure cables or chains to the
suspension components.
■Recreational towing (behind motor
home, etc.)
Never dinghy tow your vehicle to pre-
vent causing serious damage to the
AWD system and transmission.
(  P.133)
Situations when it is necessary to
contact dealers before towing
Towing with a wheel-lift type
truck

3337-2. Steps to take in an emergency
7
When trouble arises
From the rear
Use a towing dolly under the front
wheels.
When using a flat-bed truck to trans-
port the vehicle, use tire strapping
belts. Refer to the owner's manual of
the flat-bed truck for the tire strapping
method.
In order to suppress vehicle movement
during transportati on, set the parking
brake and turn the engine switch off. 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 at most 50
miles (80 km) 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 wheel bolt wrench,
flathead screwdriver and towing
eyelet. ( P.349)
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.
NOTICE
■Towing with a sling-type truck
Do not tow with a sling-type truck to pre-
vent body damage.
Using a flatbed truck
NOTICE
■Using a flatbed truck
Do not overly tighten the tie downs or the
vehicle may be damaged.
Emergency towing
Emergency towing procedure

3347-2. Steps to take in an emergency
3Insert the towing eyelet into the
hole and tighten partially by hand.
4 Tighten down the towing eyelet
securely using a wheel bolt 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 engine.
If the engine does not start, turn the engine
switch to IGNITION ON mode.
7Shift the shift lever to N and release
the parking brake.
Turn automatic mode off. ( P.144)
When the shift lever cannot be shifted:
 P.139
■While towing
If the engine is not running, the power assist
for the brakes and steering will not function,
making steering and braking more difficult.
■Wheel bolt wrench
Wheel bolt wrench is in stalled in the trunk.
(  P.349)

3437-2. Steps to take in an emergency
7
When trouble arises
■Slip indicator
■Parking brake indicator (warning buzzer)
■Brake hold operated indicator (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 sw itch, front passenger
occupant classificatio n 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 and force limiters, airbags,
interconnecting wiring and power sources.
(  P.28)
■If the malfunction indicator lamp comes
on while driving
First check the following:
Warning lightDetails/Actions
Indicates a malfunction in:
 The VSC system;
 The TRAC system; or
 The hill-start assist control system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
(flashes)
(U.S.A.)
or
(flashes)
(Canada)
It is possible that the parking brake is not fully engaged or released
 Operate the parking brake switch once again.
This light comes on when the parking brake is not released. If the light
turns off after the parking brake is fu lly released, the system is operating
normally.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.

3447-2. Steps to take in an emergency
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving
trips.
If the light does not go off even after several
trips, contact your Lexus dealer as soon as
possible.
■Electric power steering system warning
light (warning buzzer)
When the battery charge becomes insuffi-
cient or the voltage temporarily drops, the
electric power steeri ng 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.349
If none of the tires are punctured:
Turn the engine switch off then turn it to
IGNITION ON mode. Check if the tire
pressure warning light comes on or blinks.
If the tire pressure wa rning light blinks for
approximately 1 minute then stays on
There may be a malfunction in the tire
pressure warning syst em. Have the vehicle
inspected by your Lexus dealer immedi-
ately.
If the tire pressure warning light comes
on
1 After the temperature of the tires has
lowered sufficiently, check the inflation
pressure of each tire and adjust them to
the specified level.
2 If the warning light does not turn off
even after several minutes have
elapsed, check that the inflation pres-
sure of each tire is at the specified level
and perform initialization. ( P.308)
■The tire pressure warning light may
come on due to natural causes
The tire pressure wa rning light may come
on due to natural causes such as natural air
leaks and tire inflation pressure changes
caused by temperature. In this case, adjust-ing the tire inflation pressure will turn off the
warning light (after a few minutes).
■When a tire is replaced with the spare
tire
The spare tire is not equipped with a tire
pressure warning valve and transmitter. If a
tire goes flat, the tire pressure warning light
will not turn off even though the flat tire has
been replaced with the spare tire.
■Conditions that the tire pressure warn-
ing system may not function properly
 P.306
WARNING
■If both the ABS and the brake system
warning lights remain on
Stop your vehicle in a safe place immedi-
ately and contact your Lexus dealer.
The vehicle will become extremely
unstable during br aking, and the ABS
system may fail, which could cause an
accident resulting in death or serious
injury.
■When the electric power steering
system warning light comes on
When the light comes on yellow, the
assist to the power st eering is restricted.
When the light comes on red, the assist
to the power steering is lost and handling
operations of the steering wheel become
extremely heavy.
When steering wheel operations are
heavier than usual, grip the steering
wheel firmly and operate it using more
force than usual.
■If the tire pressure warning light
comes on
Be sure to observe the following precau-
tions.
Failure to do so could cause a loss of
vehicle control and result in death or
serious injury.
●Decelerate to the lowest appropriate
speed as soon as possible. Do not
drive over 50 mph (80 km/h).

3517-2. Steps to take in an emergency
7
When trouble arises
1Remove the luggage mat.
2 Take out the jack handle from the
reverse side of the luggage mat.
Remove the spacer. 3
Take out the jack.
1 For tightening
2 For loosening
If the jack is too tightly installed to be
removed by hand, insert a tool, such as the
screwdriver included wi th the vehicle, into
the hole of the jack (portion ) and
loosen the jack.
1 Remove the luggage mat.
2 Remove the spacer and tool tray.
3 Loosen the center fastener that
secures the spare tire.
If the center fastener cannot be turned by
hand, use the wheel bolt wrench that is
stored in the trunk. (To secure the tire,
tighten the center fastener by hand. Do not
WARNING
●Do not raise the vehicle while some-
one is inside.
●When raising the vehicle, do not put an
object on or under the jack.
●Do not raise the vehicle to a height
greater than that required to replace
the tire.
●Use a jack stand if it is necessary to get
under the vehicle.
●When lowering the vehicle, make sure
that there is no-one near the vehicle. If
there are people nearby, warn them
vocally before lowering.
Taking out the jack and jack han-
dle
Taking out the spare tire
A

3537-2. Steps to take in an emergency
7
When trouble arises
Turn the guide pin clockwise to tighten it
until it stops.
6Remove all the wheel bolts and the
tire.
When resting the tire on the ground, place
the tire so that the wh eel design faces up to
avoid scratching the wheel surface.
1 Remove any dirt or foreign matter
from the wheel contact surfaces
and wheel bolts.
If foreign matter is on the wheel contact
surface, the wheel bolt s may loosen while the vehicle is in motion, causing the tire to
come off.
2
Align a wheel bolt hole on the spare
tire with the guide pin, and set the
spare tire on the guide pin.
Securely set the spare tire so that its wheel
is touching the contact surface.
3Loosely tighten each wheel bolt by
hand or using a wheel bolt socket
.
Push the spare tire to prevent it from falling.
Do not use the wheel bolt socket for any-
thing other than loosely tightening the
wheel bolts by hand.
WARNING
■Replacing a flat tire
Do not touch the disc wheels or the area
around the brakes immediately after the
vehicle has been driven. After the vehicle
has been driven the disc wheels and the
area around the brakes will be extremely
hot. Touching these areas with hands,
feet or other body pa rts while changing a
tire, etc. may result in burns.
Installing the spare tire
A