check engine TOYOTA COROLLA 2020 (in English) Service Manual

4447-3. Do-it-yourself maintenance
COROLLA_U
Check if the treadwear indica-
tors are showing on the tires.
Also check the tires for uneven
wear, such as excessive wear
on one side of the tread.
Check the spare tire condition
and pressure if not rotated.New tread
Worn tread
Treadwear indicator
The location of treadwear indicators
is shown by a “TWI” or “ ” mark,
WARNING
■When adding washer fluid
Do not add washer fluid when the
engine is hot or running as
washer fluid contains alcohol and
may catch fire if spilled on the
engine, etc.
NOTICE
■Do not use any fluid other
than washer fluid
Do not use soapy water or engine
antifreeze instead of washer fluid.
Doing so may cause streaking on
the vehicle’s painted surfaces, as
well as damaging the pump lead-
ing to problems of the washer
fluid not spraying.
■Diluting washer fluid
Dilute washer fluid with water as
necessary.
Refer to the freezing tempera-
tures listed on the label of the
washer fluid bottle.
Tires
Replace or rotate tires in
accordance with mainte-
nance schedules and tread-
wear.
Checking tires

4577-3. Do-it-yourself maintenance
COROLLA_U
7
Maintenance and care
1 Turn the engine switch off.
2 Open the glove box. Slide off
the damper (if equipped).
3 Push in the glove box on the
vehicle’s outer side to discon-
nect the claws. Then pull out
the glove box and disconnect
the lower claws.
4 Unlock the filter cover ( ),
pull the filter cover out of the claws ( ), and remove the
filter cover.
5 Remove the filter case.
6 Remove the air conditioning
filter from the filter case and
replace it with a new one.
The “ UP” marks shown on the
filter and the filter case should be
pointing up.
■Checking interval
Replace the air conditioning filter
according to the maintenance
schedule. In dusty areas or areas
with heavy traffic flow, early replace-
Air condition ing filter
The air conditioning filter
must be changed regularly
to maintain air conditioning
efficiency.
Removing the air condi-
tioning filter

4617-3. Do-it-yourself maintenance
COROLLA_U
7
Maintenance and care
1 Turn the engine switch off.
2 Open the fuse box cover.
Engine compartment: type A
fuse box
Push the tabs in and lift the lid off.
Engine compartment: type B
fuse box
Push the tabs in and lift the lid off.
NOTICE
●Do not touch or move any other
component inside the remote
control.
●Do not bend either of the battery
terminals.
■When removing the battery
cover (vehicles without a
smart key system)
Do not forcibly remove the battery
cover, otherwise it may be dam-
aged.
If the battery cover is difficult to
remove, lift the edge to remove it.
Checking a nd replac-
ing fuses
If any of the electrical com-
ponents do not operate, a
fuse may have blown. If this
happens, check and replace
the fuses as necessary.
Checking and replacing
fuses

4888-2. Steps to take in an emergency
COROLLA_U
■Electric power steering system
warning light (warning buzzer)
When the battery charge becomes
insufficient or the voltage temporar-
ily 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 (vehicles with a
tire pressure warning system)
Inspect the tires to check if a tire is
punctured.
If a tire is punctured: P.493, 503
If none of the tires are punctured:
Turn the engine switch off then turn
it to ON. Check if the tire pressure
warning light comes on or blinks.
If the tire pressure warning light
blinks for approximately 1 minute
then stays on
There may be a malfunction in the
tire pressure warning system. Have
the vehicle inspected by your Toyota
dealer immediately.
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 pressure of each tire is
at the specified level and perform
initialization. ( P.450)
■The tire pressure warning light
may come on due to natural
causes (vehicles with a tire
pressure warning system)
The tire pressure warning light may
come on due to natural causes such
as natural air leaks and tire inflation
pressure changes caused by tem-
perature. In this case, adjusting the
tire inflation pressu re will turn off the
warning light (after a few minutes).
■When a tire is replaced with a
spare tire (vehicles with a tire
pressure warning system)
Vehicles with a compact spare tire:
The compact spare tire is not
equipped with a tire pressure warn-
ing 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. Replace the spare tire
with the repaired tire and adjust the
tire inflation pressure. The tire pres-
sure warning light will go off after a
few minutes.
■Conditions that the tire pres-
sure warning system may not
function properly (vehicles with
a tire pressure warning system)
 P.447
WARNING
■If both the ABS and the brake
system warning lights remain
on
Stop your vehicle in a safe place
immediately and contact your Toy-
ota dealer.
The vehicle will become
extremely unstable during brak-
ing, 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 steering is
restricted. When the light comes
on red, the assist to the power
steering is lost and handling oper-
ations 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.

4908-2. Steps to take in an emergency
COROLLA_U
■Warning messages
The warning messages explained
below may differ from the actual
messages according to operation
conditions and vehicle specifica-
tions.
■Warning buzzer
A buzzer may sound when a mes-
sage is displayed.
The buzzer may not be audible if the
vehicle is in a noisy location or if the
audio system volume is high.
■If “Engine Oil Level Low Add or
Replace” is displayed
The engine oil level is low. Check
WARNING
Your vehicle has also been
equipped with a TPMS (tire pres-
sure warning system) malfunc-
tion indicator to indicate when the
system is not operating properly.
The TPMS (tire pressure warning
system) malfunction indicator is
combined with the low tire pres-
sure telltale (tire pressure warning
light). When the system detects a
malfunction, the telltale will flash
for approximately one minute and
then remain cont inuously illumi-
nated. This sequence will con-
tinue upon subsequent vehicle
start-ups as long as the malfunc-
tion exists. When the malfunction
indicator is illuminated, the sys-
tem may not be able to detect or
signal low tire pressure as
intended.
TPMS (tire pressure warning sys-
tem) malfunctions may occur for a
variety of reasons, including the
installation of replacement or
alternate tires or wheels on the
vehicle that prevent the TPMS
(tire pressure warning system)
from functioning properly. Always
check the TPMS (tire pressure
warning system) malfunction tell-
tale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow
the TPMS (tire pressure warning
system) to continue to function
properly.
NOTICE
■To ensure the tire pressure
warning system operates
properly (vehicles with a tire
pressure warning system)
Do not install tires with different
specifications or makers, as the
tire pressure wa rning system may
not operate properly.
If a war ning message
is displayed
The multi-information dis-
play shows warnings for
system malfunctions and
incorrectly performed oper-
ations, and messages that
indicate a need for mainte-
nance. When a message is
displayed, perform the
appropriate corrective
action for the message.
If a warning message is dis-
played again after the
appropriate actions have
been performed, contact
your Toyota dealer.
Additionally, if a warning
light comes on or flashes at
the same time that a warn-
ing message is displayed,
take the appropriate correc-
tive action for the warning
light. ( P.481)

4918-2. Steps to take in an emergency
COROLLA_U
8
When trouble arises
the level of the engine oil, and add if
necessary.
This message may appear if the
vehicle is stopped on a slope. Move
the vehicle to a level surface and
check to see if the message disap-
pears.
■If “Engine Stopped Steering
Power Low” is displayed
This message is displayed if the
engine is stopped while driving.
When steering wheel operations are
heavier than usual, grip the steering
wheel firmly and operate it using
more force than usual.
■If “Auto Power OFF to Conserve
Battery” is displayed
Power was cut off due to the auto-
matic power off function. Next time
when starting the engine, increase
the engine speed slightly and main-
tain that level for approximately 5
minutes to recharge the battery.
■If “Headlight System Malfunc-
tion Visit Your Dealer” is dis-
played
The following systems may be mal-
functioning. Have the vehicle
inspected by your Toyota dealer
immediately.
●The LED headlight system
●AFS (Adaptive Front-lighting Sys-
tem) (if equipped)
●The automatic headlight leveling
system (if equipped)
●Automatic High Beam
■If “Front Camera Unavailable”
or “Front Camera Unavailable
See Owner’s Manual” is dis-
played
The following systems may be sus-
pended until the problem shown in
the message is resolved. ( P.185,
481)
●PCS (Pre-Collision system)
●LTA (Lane Tracing Assist) (if
equipped)
●LDA (Lane Departure Alert with
steering control) (if equipped)
●Automatic High Beam
●RSA (Road Sign Assist) (if
equipped)
●Dynamic radar cruise control with
full-speed range (if equipped)
●Dynamic radar cruise control (if
equipped)
■If “Radar Cruise Control
Unavailable See Owner's Man-
ual” is displayed
The dynamic radar cruise control
with full-speed range system or
dynamic radar cruise control system
is suspended temporarily or until the
problem shown in the message is
resolved. (causes and coping meth-
ods: P.185)
■If “Radar Cruise Control
Unavailable” is displayed
The dynamic radar cruise control
with full-speed range system or
dynamic radar cruise control system
cannot be used temporarily. Use the
system when it becomes available
again.
■If “Maintenance Required
Soon” is displayed
Indicates that all maintenance
according to the driven distance on
the maintenance schedule
* should
be performed soon.
Comes on approximately 4500
miles (7200 km) after the message
has been reset. If necessary, per-
form maintenance. Please reset the
message after the maintenance is
performed. ( P.428)
*: Refer to the separate “Scheduled
Maintenance” or “Owner’s Man-
ual Supplement” for the mainte-
nance interval applicable to your
vehicle.
■If “Maintenance Required Visit
Your Dealer” is displayed
Indicates that all maintenance is

4938-2. Steps to take in an emergency
COROLLA_U
8
When trouble arises
 Stop the vehicle in a safe
place on a hard, flat surface.
 Set the parking brake.
 Shift the shift lever to P (con- tinuously variable transmis-
sion) or N (manual
transmission).
 Stop the engine.
 Turn on the emergency flash-
ers.
 Check the degree of the tire
damage.
A tire should only be repaired
with the emergency tire punc-
ture repair kit if the damage is
caused by a nail or screw pass-
ing through the tire tread.
• Do not remove the nail or screw from the tire. Removing
the object may widen the
opening and make emer-
gency repair with the repair kit
impossible.
• To avoid sealant leakage, move the vehicle until the
area of the puncture, if
known, is positioned at the
top of the tire.
■A flat tire that cannot be
repaired with the emergency
tire puncture repair kit
In the following cases, the tire can-
not be repaired with the emergency
tire puncture repair kit. Contact your
Toyota dealer.
If you have a flat tire
(vehicles without
spare tire)
Your vehicle is not equipped
with a spare tire, but instead
is equipped with an emer-
gency tire puncture repair
kit.
A puncture caused by a nail
or screw passing through
the tire tread can be
repaired temporarily using
the emergency tire puncture
repair kit. (The kit contains a
bottle of sealant. The seal-
ant can be used only once
to temporarily repair one
tire without removing the
nail or screw from the tire.)
After temporarily repairing
the tire with the kit, have the
tire repaired or replaced by
your Toyota dealer.
WARNING
■If you have a flat tire
Do not continue driving with a flat
tire.
Driving even a short distance with
a flat tire can damage the tire and
the wheel beyond repair, which
could result in an accident.
Before repairing the tire

4988-2. Steps to take in an emergency
COROLLA_Ular as shown. (
P.531)
12 Start the engine.
13 To inject the sealant and
inflate the tire, turn the com-
pressor switch on. 14Inflate the tire until the speci-
fied air pressure is reached.
The sealant will be injected
and the pressure will spike to
between 44 psi (300 kPa, 3.0
kgf/cm
2 or bar) and 58 psi
(400 kPa, 4.0 kgf/cm
2 or bar),
then gradually decrease.
The air pressure gauge will
display the actual tire inflation
pressure about 1 to 5 min-
utes after the switch is turned
on.
Turn the compressor switch off and
then check the tire inflation pres-
sure. Being careful not to over
inflate, check and repeat the infla-
tion procedure until the specified
tire inflation pressure is reached.
The tire can be inflated for about 5
to 20 minutes (depending on the
outside temperature). If the tire
inflation pressure is still lower than
the specified point after inflation for
25 minutes, the tire is too damaged

5128-2. Steps to take in an emergency
COROLLA_U
The battery terminal connec-
tions may be loose or cor-
roded. ( P.442)
The engine starting system may
be malfunctioning due to an
electrical problem such as elec-
tronic key battery depletion or a
blown fuse. However, an interim
measure is available to start the
engine. ( P.512)
One of the following may be the
cause of the problem:
 The battery may be dis-
charged. ( P.515)
 One or both of the battery ter-
minals may be disconnected.
( P.442)
 There may be a malfunction
in the steering lock system.
Contact your Toyota dealer if the
problem cannot be repaired, or if
repair procedures are unknown.
When the engine does not start,
the following steps can be used
as an interim measure to start
the engine if the engine switch is
functioning normally.
Do not use this starting proce-
dure except in case of emer-
gency.
1 Set the parking brake.
( P.163, 164)
2 Check that the shift lever is in
P (continuously variable
transmission) or N (manual
transmission).
3 Turn the engine switch to
ACC.
4 Press and hold the engine
switch for about 15 seconds
while depressing the brake
pedal (continuously variable
transmission) or clutch pedal
(manual transmission) firmly.
Even if the engine can be started
using the above steps, the system
may be malfunctioning. Have the
vehicle inspected by your Toyota
dealer.
The starter motor does
not turn over (vehicles
with a smart key system)
The starter motor does
not turn over, the interior
lights and headlights do
not turn on, or the horn
does not sound.
Emergency start function
(vehicles with a smart key
system)

5138-2. Steps to take in an emergency
COROLLA_U
8
When trouble arises
■When the electronic key does
not work properly
●Make sure that the smart key sys-
tem has not been deactivated in
the customization setting. If it is
off, turn the function on. (Custom-
izable features: P.548)
●Check if battery-saving mode is
set. If it is set, cancel the function.
( P. 1 1 3 )
Use the mechanical key
( P.100) in order to perform the
If you lose your keys
New genuine keys can be
made by your Toyota dealer
using the other key (vehi-
cles without a smart key
system) or mechanical key
(vehicles with a smart key
system) and the key number
stamped on your key num-
ber plate.
Keep the plate in a safe
place such as your wallet,
not in the vehicle.
NOTICE
■When an electronic key is lost
(vehicles with a smart key
system)
If the electronic key remains lost,
the risk of vehicle theft increases
significantly. Visit your Toyota
dealer immediately with all
remaining electronic keys that
were provided with your vehicle.
If the electronic key
does not operate prop-
erly (vehicles with a
smar t key system)
If communication between
the electronic key and vehi-
cle is interrupted ( P.113)
or the electronic key cannot
be used because the battery
is depleted, the smart key
system and wireless remote
control cannot be used. In
such cases, the doors can
be opened and the engine
can be started by following
the procedure below.
NOTICE
■In case of a smart key system
malfunction or other
key-related problems
Take your vehicle with all the elec-
tronic keys provided with your
vehicle to your Toyota dealer.
Locking and unlocking
the doors