ECU MAZDA MODEL 3 HATCHBACK 2021 Repair Manual

▼Brake Override Warning Indication
This message is displayed when the
accelerator pedal and brake pedal are
depressed at the same time while
driving.
Release the accelerator pedal and
depress the brake pedal.
▼Check Engine Indication/Light
If this light illuminates while driving ,
the vehicle may have a problem. It is
important to note the driving
conditions when the light illuminated
and consult an Authorized Mazda
Dealer.
The check engine light may illuminate
in the following cases:
The engine's electrical system has a
problem.
The emission control system has a
problem.
The fuel-
filler cap is missing or not
tightened securely.
The fuel tank level being very low or
approaching empty.
If the check engine light remains on, or
it flashes continuously , do not drive at
high speeds and consult an Authorized
Mazda Dealer as soon as possible.
WARNING
If the check engine light turns on, do
not disconnect the battery cables.
If the battery cables are disconnected
and then reconnected, the engine
could be damaged and catch on fire.
▼Automatic Transmission Warning
Indication/Warning Light*
The indication/light illuminates when
the transmission has a problem.
CAUTION
If the automatic transmission warning
indication/light illuminates, the
transmission has an electrical problem.
Continuing to drive your Mazda in this
condition could cause damage to your
transmission. Consult an Authorized
Mazda Dealer as soon as possible.
▼
AWD Warning Indication/
Warning Light*
“AWD Malfunction. Front Wheel
Drive Only. Have the Vehicle
Inspected” is displayed/When the
light is turned on
The indication is displayed/the light
turns on under the following
conditions. The system may have a
malfunction. Have the vehicle checked
at an Authorized Mazda Dealer.
If Trouble Arises
Warning/Indicator Lights and Warning Sounds
*Some models.7-31
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“Key Not Detected” is displayed
If the presence of the key cannot be
detected (dead battery, battery
malfunction, no key), it is displayed
when the driver attempts to start the
engine (push button start operation,
brake pedal depression).
Displayed when it is determined that
a key that was in the vehicle has
been removed from the vehicle. (Key
taken out warning. Other thanIG -OFF).
▼ Security Indicator Light
If the security indicator light
flashes
continuously while you are driving , do
not shut o ff the engine. Go to an
Authorized Mazda Dealer and have it
checked. If the engine is shut o ff while
the indicator light is flashing, you will
not be able to restart it.
Make sure the key is within the
operational range for signal
transmission. Switch the ignition o ff,
and then restart the engine. If the
engine does not start after 3 or more
tries, contact an Authorized Mazda
Dealer.
NOTE
Because the electronic codes are reset
when the immobilizer system is
repaired, the keys are needed. Make
sure to bring all the keys to an
Authorized Mazda Dealer so that they
can be programmed.
▼ High Beam Control System (HBC)
Warning Indication/Warning Light
(Amber)
*
The light remains turned on if there is a
problem with the system. Have your
vehicle inspected at an Authorized
Mazda Dealer.
▼i-ACTIVSENSE Warning
Indication/Warning Light*
The indication displays if the system
has a malfunction.
Check the reason for the indication
displaying on the center display or
multi-information display.
Refer to If a Warning Light Turns On or
Flashes on page 7-27.
▼Exterior Light Warning Indication/
Warning Light
This light illuminates if there is a
malfunction in the exterior lights
(except license plate lights). Have your
vehicle inspected by an Authorized
Mazda Dealer.
If Trouble Arises
Warning/Indicator Lights and Warning Sounds
7-34*Some models.
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▼Door-Ajar/Trunk lid-Ajar/
Liftgate-Ajar Warning Indication/
Warning Light
The light turns on if any door/trunk
lid/liftgate is not closed securely.
Action to be taken
Close the door/trunk lid/liftgate
securely.
▼Tire Pressure Monitoring System
(TPMS) Warning Indication/
Warning Light (Turns on)
If a tire pressure decreases below the
speci
fied air pressure, the TPMS
warning light turns on.
At the same time, a message and the
tire pressure of each tire are displayed
on the multi-information display
alternately. In addition, the tire (s) with
low air pressure is displayed in yellow.
WARNING
Do not drive the vehicle at high
speeds if the TPMS warning light turns
on or flashes:
Driving the vehicle at high speeds
while the TPMS warning light is turned
on or fl ashing is dangerous because
the brake performance and the
steering wheel operability will be
reduced. If the vehicle is driven at high
speeds or the brakes are suddenly
applied, it could lead to an accident.
Gradually apply the brakes to lower the
vehicle's speed.
Do not ignore the TPMS warning light
when it is turned on or flashing:
Continuing to drive the vehicle while
ignoring the illumination/ flashing of
the TPMS warning light is dangerous
because a tire may burst which could
lead to an accident. Take appropriate
measures as soon as possible.
NOTE
While the TPMS is learning the tire
positions, such as immediately after a
tire position has been changed, the tire
pressure at the tire position prior to it
being changed is displayed until the
system completes the learning. For this
reason, the tire pressures displayed for
the tire positions may be di fferent from
the actual tire pressures at the tire
positions.
Action to be taken
Adjust the tire pressures to the
appropriate pressures.
Refer to Tire In flation Pressure on page
6-34.
If Trouble Arises
Warning/Indicator Lights and Warning Sounds
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Index
Fuse..................................... 6-40
Key battery........................... 6-31
Light bulbs........................... 6-37
Tires.....................................6-35
Wheel.................................. 6-37
Wiper.................................. 6-23
Rocking the Vehicle................... 3-46
S
Safety Defects, Reporting
(Canada).................................. 8-14
Safety Defects, Reporting
(U.S.A.).................................... 8-12
Saving Fuel and Protection of the
Environment............................. 3-44
Scheduled Maintenance Canada.................................. 6-6
Mexico.................................. 6-9
U.S.A. and Puerto Rico........... 6-4
Seats Driver's seat........................... 2-5
Front passenger's seat........... 2-13
Front seat............................... 2-5
Head restraint...................... 2-17
Rear seat.............................. 2-14
Seat warmer......................... 2-20
Seat Belt System Automatic locking................ 2-25
Emergency locking................ 2-25
Extender.............................. 2-30
Pregnant women.................. 2-25
Seat belt precautions............ 2-23
Seat Belt Warning Beep............. 7-42
Security System Immobilizer system............... 3-40
Theft-deterrent system.......... 3-42
Shift Position Warning Beep....... 7-45
Smart Brake Support (SBS)....... 4-158 Collision warning................ 4-159
Stopping the Smart Brake Support
(SBS) system operation........4-160
Smart Brake Support [Rear Crossing]
(SBS- RC).................................4-164
Collision warning................ 4-167
Stopping the Smart Brake Support
[Rear Crossing] (SBS-RC) system
operation........................... 4-168
Smart Brake Support [Rear] (SBS -
R) ........................................... 4-160
Collision warning................ 4-163
Stopping the Smart Brake Support
[Rear] (SBS-R) system
operation........................... 4-163
Spare Tire................................... 7-5
Spare Tire and Tool Storage.......... 7-3
Speci fications
Capacities.............................. 9-5
Dimensions............................ 9-6
Electrical system..................... 9-4
Engine................................... 9-4
Light bulbs............................. 9-9
Lubricant quality..................... 9-5
Tires.....................................9-10
Weights................................. 9-7
SRS Air Bags Driver and front passenger
occupant classification
system................................. 2-70
How the SRS air bags work.... 2-63
Limitations to SRS air bag...... 2-69
Monitoring........................... 2-75
SRS air bag deployment
criteria................................. 2-67
Supplemental restraint system
components......................... 2-61
Supplemental restraint system
(SRS) precautions................. 2-55
Starting the Engine...................... 4-5
Steering Wheel Heated steering wheel.......... 2-21
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