ECU TOYOTA COROLLA 2023 Repair Manual

3497-1. Essential information
7
When trouble arises
turning the engine switch to
ACC.
4 Vehicles with a smart key
system: To stop the engine,
press and hold the engine
switch for 2 consecutive sec-
onds or more, or press it
briefly 3 times or more in suc-
cession.
5 Stop the vehicle in a safe
place by the road.
WARNING
■If the engine has to be turned
off while driving
●Power assist for the brakes and
steering wheel will be lost, mak-
ing the brake pedal harder to
depress and the steering wheel
heavier to turn. Decelerate as
much as possible before turning
off the engine.
●Vehicles without a smart key
system: Never attempt to
remove the key, as doing so will
lock the steering wheel.

3517-2. Steps to take in an emergency
7
When trouble arises
7-2.Steps to take in an emergency
If your vehicle needs
to be towed
If towing is necessary, we
recommend having your
vehicle towed by your Toy-
ota dealer or commercial
towing service, using a
wheel-lift type truck or flat-
bed truck.
Use a safety chain system
for all towing, and abide by
all state/provincial and local
laws.
WARNING
Observe the following precau-
tions.
Failure to do so may result in
death or serious injury.
■When towing the vehicle
Be sure to transport the vehicle
with the front wh eels raised or
with all four wheels raised off the
ground. If the vehicle is towed
with the front wh eels contacting
the ground, the drivetrain and
related parts may be damaged.
■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
damaged, broken debris may hit
people, and cause serious dam-
age.
●Do not turn the engine switch
off.
There is a possibility that the
steering wheel is locked and
cannot be operated.
■Installing towing eyelets to
the vehicle
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 t owing using a
wheel-lift type truck
●Vehicles without a smart key
system: Do not tow the vehicle
from the rear when the engine
switch is off or the key is
removed. The steering lock
mechanism is not strong
enough to hold the front wheels
straight.
●Vehicles with a smart key sys-
tem: Do not tow the vehicle from
the rear when the engine switch
is off.
●When raising the vehicle,
ensure adequate ground clear-
ance for towing at the opposite
end of the raised vehicle. With-
out adequate clearance, the
vehicle could be damaged while
being towed.

3527-2. Steps to take in an emergency
The following may indicate a
problem with your transmission.
Contact your Toyota dealer or
commercial towing service
before towing.
The engine is running but the
vehicle does not move.
 The vehicle makes an abnor-
mal sound.
From the front
Release the parking brake. Turn automatic mode off.
(
P.169)
From the rear
Use a towing dolly under the
front wheels.
When using a flat-bed truck to
transport 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 transporta-
tion, set the parking brake and
turn the engine switch off.
NOTICE
■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.
Situations when it is nec-
essary to contact dealers
before towing
Towing with a wheel-lift
type truck
NOTICE
■Towing with a sling-type truck
Do not tow with a sling-type truck
to prevent body damage.
Using a flatbed truck

3537-2. Steps to take in an emergency
7
When trouble arises
If a tow truck is not available in
an emergency, your vehicle may
be temporarily towed using
cables or chains secured to the
emergency towing eyelets. 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.
For vehicles with a continuously
variable transmission, only the
front towing eyelets may be
used.
To have your vehicle towed by
another vehicle, the towing eye-
let must be installed to your
vehicle. Install the towing eyelet
using the following procedure.
1Take out the wheel nut
wrench and towing eyelet.
( 371)
2 Remove the eyelet cover
using a flathead screwdriver.
To protect the bod ywork, place a
rag between the screwdriver and
the vehicle body as shown in the
illustration.
Type A
Type B
3 Insert the towing eyelet into
the hole and tighten partially
by hand.
Emergency towing (vehi-
cles with a towing eyelet)
Emergency towing proce-
dure (vehicles with a tow-
ing eyelet)

3547-2. Steps to take in an emergency
4Tighten down the towing eye-
let 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 vehi-
cle body.
6Enter the vehicle being towed
and start the engine.
If the engine does not start, turn the
engine switch to ON.
7Shift the shift lever to N and
release the parking brake.
Turn automatic mode off.
( P.169)
When the shift lever cannot
be shifted:  P. 1 6 1
■While towing (vehicles with a
towing eyelet)
If the engine is not running, the
power assist for the brakes and
steering will not function, making
steering and braking more difficult.
■Wheel nut wrench (vehicles
with a towing eyelet)
Wheel nut wrench is installed in
trunk. ( P.371)
 Fluid leaks under the vehicle.
(Water dripping from the air
conditioning after use is nor-
mal.)
 Flat-looking tires or uneven
tire wear
 Engine coolant temperature
gauge needle continually
points higher than normal.
 Changes in exhaust sound
 Excessive tire squeal when
cornering
 Strange noises related to the
suspension system
 Pinging or other noises
related to the engine
 Engine missing, stumbling or
running roughly
 Appreciable loss of power
 Vehicle pulls heavily to one
If you think something
is wrong
If you notice any of the fol-
lowing symptoms, your
vehicle probably needs
adjustment or repair. Con-
tact your Toyota dealer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms

3747-2. Steps to take in an emergency
3Loosen the center fastener
that secures the spare tire.
1 Chock the tires. 2
Vehicles with a steel wheel:
Remove the wheel cap (if
equipped) using the wrench.
Insert the wrench i nto the notch
on the wheel cap.
To protect the whee l cap, place a
rag between the wrench and the
wheel cap.
3 Slightly loosen the wheel
nuts (one turn).
4 Turn the tire jack portion
by hand until the center of the
recessed portion of the jack
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
Flat tireWheel chock positions

3787-2. Steps to take in an emergency
WARNING
■When using the compact
spare tire
●Remember that the compact
spare tire provided is specifi-
cally designed for use with your
vehicle. Do not use your com-
pact spare tire on another vehi-
cle.
●Do not use more than one com-
pact spare tires simultaneously.
●Replace the compact spare tire
with a standard tire as soon as
possible.
●Avoid sudden acceleration,
abrupt steering, sudden brak-
ing and shifting operations that
cause sudden engine braking.
■When the compact spare tire
is attached
The vehicle speed may not be
correctly detecte d, and the follow-
ing systems may not operate cor-
rectly:
• ABS & Brake assist
• VSC
• TRAC
• Automatic High Beam
• Dynamic radar cruise control
• EPS
• PCS (Pre-Collision System)
• LDA (Lane Departure Alert)
• LTA (Lane Tracing Assist)
• Tire pressure warning system (if equipped)
• BSM (if equipped)
• RCTA (if equipped)
• SEA (if equipped)
• Rear view monitor system
• Navigation system (if equipped)
■Speed limit when using the
compact spare tire
Do not drive at speeds in excess
of 50 mph (80 km /h) when a com-
pact 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 acci-
dent causing death or serious
injury.
■After using the tools and jack
Before driving, ma ke 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 sur-
faces.

3857-2. Steps to take in an emergency
7
When trouble arises
approximately 5 minutes to
recharge the battery of your
vehicle.
5 Vehicles with a smart key
system: Open and close any
of the doors of your vehicle
with the engine switch OFF.
6 Maintain the engine speed of
the second vehicle and start
the engine of your vehicle by
turning the engine switch to
ON.
7 Once the vehicle’s engine
has started, remove the
jumper cables in the exact
reverse order from which
they were connected.
Once the engine starts, have the
vehicle inspected at your Toyota
dealer as soon as possible.
■Starting the engine when the
battery is discharged
The engine cannot be started by
push-starting.
■To prevent battery discharge
●Turn off the headlights and the
audio system while the engine is
off.
●Turn off any unnecessary electri-
cal components when the vehicle
is running at a low speed for an
extended period, such as in heavy
traffic.
■When the battery is removed or
discharged
●Information stor ed in the ECU is
cleared. When the battery is
depleted, have the vehicle
inspected at you r Toyota dealer.
●Some systems may require initial-
ization. ( P.422)
■When removing the battery ter-
minals
When the battery terminals are
removed, the information stored in
the ECU is cleared. Before remov-
ing the battery term inals, contact
your Toyota dealer.
■Charging the battery
The electricity stored in the battery
will discharge grad ually even when
the vehicle is not in use, due to nat-
ural discharge and the draining
effects of certain electrical appli-
ances. If the vehicle is left for a long
time, the battery may discharge,
and the engine may be unable to
start. (The battery recharges auto-
matically during driving.)
■When recharging or replacing
the battery (vehicles with a
smart key system)
●In some cases, it may not be pos-
sible to unlock the doors using the
smart key system when the bat-
tery is discharged. Use the wire-
less remote control or the
mechanical key to lock or unlock
the doors.
●The engine may not start on the
first attempt after the battery has
recharged but will start normally
after the second attempt. This is
not a malfunction.
●The engine switch mode is memo-
rized by the vehicle. When the
battery is reconnected, the system
will return to the mode it was in
before the bat tery was dis-
charged. Before disconnecting the
battery, turn the engine switch off.
If you are unsure what mode the
engine switch wa s in before the
battery discharged, be especially
careful when reconnecting the
battery.
■When replacing the battery
●Use a battery that conforms to
European regulations.
●Use a battery that the case size is
same as the previous one (LN1),

3867-2. Steps to take in an emergency
20 hour rate capacity (20HR) is
equivalent (45Ah) or greater, and
performance rating (CCA) is
equivalent (286A or 307A) or
greater.
• If the sizes differ, the battery can-
not be properly secured.
• If the 20 hour rate capacity is low,
even if the time period where the
vehicle is not used is a short time,
the battery may discharge and the
engine may not be able to start.
●For details, consu lt your Toyota
dealer.
WARNING
■When removing the battery
terminals
Always remove the negative (-)
terminal first. If the positive (+) ter-
minal contacts any metal in the
surrounding area when the posi-
tive (+) terminal is removed, a
spark may occur, l eading to a fire
in addition to electrical shocks
and death or serious injury.
■Avoiding battery fires or
explosions
Observe the following precautions
to prevent accidentally igniting the
flammable gas that may be emit-
ted from the battery:
●Make sure each jumper cable is
connected to the correct termi-
nal and that it is not unintention-
ally in contact with any other
than the intended terminal.
●Do not allow the other end of
the jumper cable connected to
the “+” terminal to come into
contact with any other parts or
metal surfaces in the area, such
as brackets or unpainted metal.
●Do not allow the + and - clamps
of the jumper cables to come
into contact with each other.
●Do not smoke, use matches,
cigarette lighter s or allow open
flame near the battery.
■Battery precautions
The battery contains poisonous
and corrosive acidic electrolyte,
while related parts contain lead
and lead compounds. Observe
the following precautions when
handling the battery:
●When working with the battery,
always wear safety glasses and
take care not to allow any bat-
tery fluids (acid) to come into
contact with skin, clothing or the
vehicle body.
●Do not lean over the battery.
●In the event that 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.
●Always wash your hands after
handling the battery support,
terminals, and other bat-
tery-related parts.
●Do not allow children near the
battery.
NOTICE
■When handling jumper cables
When connecting the jumper
cables, ensure that they do not
become entangled in the cooling
fan or engine drive belt.

4108-1. Specifications
*: Table 1 -Occupant loading and distribution for vehicle normal load for var-
ious designated seating capacities
Sidewall separationThe parting of the rubber compound from
the cord materia l in the sidewall
Snow tire
A tire that attains a traction index equal to
or greater than 110, compared to the
ASTM E-1136 Standard Reference Test
Tire, when using the snow traction test as
described in ASTM F-1805-00, Standard
Test Method for Single Wheel Driving Trac-
tion in a Straight Line on Snow-and
Ice-Covered Surfaces, and which is
marked with an Alpine Symbol ( ) on at
least one sidewall
Te s t r i m
The rim on which a tire is fitted for testing,
and may be any rim lis ted as appropriate
for use with that tire
TreadThat portion of a tire that comes into con-
tact with the road
Tread ribA tread section running circumferentially
around a tire
Tread separationPulling away of the tread from the tire car-
cass
Treadwear indicators (TWI)
The projections wit hin the principal
grooves designed to g ive a visual indica-
tion of the degrees of wear of the tread
Wheel-holding fixtureThe fixture used to hol d the wheel and tire
assembly securely during testing
Tire related termMeaning
Designated seating
capacity, Number of occupantsVehicle normal load,
Number of occupantsOccupant distribution in a normally loaded vehi- cle
2 through 422 in front
5 through 1032 in front, 1 in second seat