2021 HONDA CIVIC SEDAN ECU

Contents
Child Safety P. 62Exhaust Gas Hazard P. 75Safety Labels P. 76
Opening and Closing the Trunk P. 142 Security System P. 145 Opening and Closing the Windows P. 148
Adjusting the Mirrors P. 170 Adjusting the Seats P. 172
Climate Control System P. 193
Audio Error Messages P. 297 General Information on the Audio System P. 300
Bluetooth ® HandsFreeLink ® P. 355, 382
When Driving P. 422 Honda Sensing ® P. 450 Braking P. 494 Parki ng Your Vehicle P. 501
Fuel Economy and CO
2 Emissions P. 508 Turbo Engine Vehicle* P. 509
Maintenance Under the Hood P. 521 Replacing Light Bulbs P. 536
Checking and Maintaining Tires P. 548 Battery P. 558 Remote Transmitter Care P. 560
Cleaning P. 563 Accessories and Modifications P. 568
Engine Does Not Start P. 580 If the Battery Is Dead P. 583
Indicator, Coming On/Blinking P. 589 Fuses P. 595Emergency Towing P. 599
If You Cannot Open the Trunk P. 601 Refueling P. 602
Devices that Emit Radio Waves P. 609 Reporting Safety Defects P. 610
Authorized Manuals P. 616 Customer Service Information P. 617
Quick Reference GuideP. 6
Safe DrivingP. 33
Instrument PanelP. 77
ControlsP. 125
FeaturesP. 201
DrivingP. 415
MaintenanceP. 511
Handling the UnexpectedP. 571
InformationP. 603
IndexP. 619
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Quick Reference Guide❚Seat Belt to Secure a Child Seat (P71)
❚Seat Belt (Installing a Child Seat) (P69)
❚Moonroof Switch* (P151)
❚Front Seat (P172)
❚Seat Belts (P38)
❚Side Airbags (P54)
❚Rear Seat (P175)
❚LATCH to Secure a Child Seat (P67)
❚Ceiling Light (P180)
❚Side Curtain Airbags (P56)
❚Coat Hook (P190)
❚Grab Handle
❚Coat Hook (P190)
❚Sun Visors
❚Vanity Mirrors
❚Map Lights (P181)
* Not available on all models
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Quick Reference Guide
Instrument Panel (P 77)
System Indicators
Malfunction Indicator
Lamp
Low Oil Pressure
Indicator
Charging System
Indicator
Anti-lock Brake System
(ABS ) Indicator
Vehicle Stability
Assist
TM (VSA ®)
System Indicator
Vehicle Stability
Assist
TM (VSA ®) OFF
Indicator
Low Tire Pressure/
TPMS Indicator
*
Electric Power
Steering (EPS) System
Indicator
Seat Belt Reminder
Indicator
System Indicators
Parking Brake and
Brake System
Indicator (Red) Supplemental
Restraint System
Indicator
Tachometer
Speedometer Fuel Gauge
Immobilizer System
Indicator/Security
System Alarm Indicator
Shift Lever Position Indicator/
Transmission System Indicator
Low Fuel Indicator
ECON Mode Indicator Turn Signal and
Hazard Warning
Indicators
Parking Brake and
Brake System
Indicator (Amber)
System Indicators
U.S.
Canada
U.S.
Canada Automatic Brake Hold
System Indicator
Automatic Brake Hold
IndicatorU.S.
Canada Temperature Gauge
Lights Indicators
Lights On Indicator
High Beam Indicator
Fog Light Indicator*
Adaptive Cruise
Control (ACC) with
Low Speed Follow
Indicator (Amber/
Green)
System Message
Indicator
Collision Mitigation
Braking SystemTM
(CMBSTM) Indicator
Road Departure
Mitigation (RDM)
Indicator
Lane Keeping Assist
System (LKAS)
Indicator (Amber/
Green)
Ambient Meter
Gauges (P 108)/Driver Information Interface (P 109)/System Indicators (P 78)
M (7-speed manual shift mode)
Indicator/Shift Indicator
*
Auto High-Beam
Indicator
* Not available on all models
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Quick Reference Guide
The rear door cannot be
opened from inside the
vehicle. Why?Check if the childproof lock is in
the lock position. If so, open the
rear door with the outside door
handle.
To cancel this function, slide the
lever up to the unlock position.
Why do the doors lock
after I unlocked the doors?If you do not open the doors within 30 seconds, the doors are
relocked automatically for security.
Why does the beeper
sound when I open the
driver's door?The beeper sounds when:
●The exterior lights are left on.
●The key is left in the ignition switch.
●The power mode is in ACCESSORY.
Why does a beeper sound
when I walk away from the
vehicle after I close the
door?The beeper sounds if you move outside the walk away auto
door lock operating range before the door completely closes.
2Locking the doors and trunk (Walk away auto lock ®) (P 133)
Models without smart entry system
Models with smart entry system
Models with smart entry system
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uuSeat Belts uFastening a Seat Belt
Safe Driving
Fastening a Seat Belt
After adjusting a front seat to the proper position, and while sitting upright and well
back in the seat:
2 Adjusting the Seats P. 172
1.Pull the seat belt out slowly.
2. Insert the latch plate into the buckle, then
tug on the belt to make sure the buckle is
secure.
u Make sure that the belt is not twisted or
caught on anything.
1Fastening a Seat Belt
No one should sit in a seat with an inoperative seat
belt or one that does not appear to be working
correctly. Using a seat be lt that is not working
properly may not protect the occupant in a crash.
Have a dealer check the belt as soon as possible.
Never insert any foreign obj ects into the buckle or
retractor mechanism.
If the seat belt appears to be locked in a fully
retracted position, firmly pull out on the shoulder belt
once, then push it back in.
Then smoothly pull it out of the retractor and fasten.
If you are unable to release the seat belt from a fully
retracted position, do not al low anyone to sit in the
seat, and take your vehicle to a dealer for repair.
2 About Your Seat Belts P. 38
2 Seat Belt Inspection P. 45
Pull out slowly.
Correct
Seated
Posture.
Latch
Plate
Buckle
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Continued43
uuSeat Belts uFastening a Seat Belt
Safe Driving
3. Position the lap part of the belt as low as
possible across your hips, then pull up on
the shoulder part of the belt so the lap part
fits snugly. This lets your strong pelvic
bones take the force of a crash and reduces
the chance of internal injuries.
4. If necessary, pull up on the belt again to
remove any slack, then check that the belt
rests across the center of your chest and
over your shoulder. Th is spreads the forces
of a crash over the strongest bones in your
upper body.
The front seats have adjustab le shoulder anchors to accommodate taller and shorter
occupants. 1.Move the anchor up and down while
pulling the shoulder anchor outward.
2. Position the anchor so that the belt rests
across the center of your chest and over
your shoulder.1 Fastening a Seat Belt
To release the belt, push the red PRESS button and
then guide the belt by hand until it has retracted
completely.
When exiting the vehicle, be sure the belt is properly
stowed so that it will not get caught in the closing
door.
3WARNING
Improperly positioning the seat belts can
cause serious injury or death in a crash.
Make sure all seat belts are properly
positioned before driving.Lap belt
as low as
possible
■Adjusting the Shoulder Anchor1 Adjusting the Shoulder Anchor
The shoulder anchor height can be adjusted to four
levels. If the belt contacts your neck, lower the height
one level at a time.
After an adjustment, make sure that the shoulder
anchor position is secure.
Pull
outward
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uuChild Safety uProtecting Child Passengers
Safe Driving
• Any child who is too small to wear a seat belt correctly must be restrained in an
approved child seat that is properly secu red to the vehicle using either the seat
belt or the lower anchors of the LATCH system.
• Never hold a child on your lap because it is impossible to protect them in the
event of a collision.
• Never put a seat belt over yourself and a child. During a crash, the belt would
likely press deep into the child and cause serious or fatal injuries.
• Never let two children use the same seat belt. Both children could be very
seriously injured in a crash.
• Do not allow children to operate the doors, windows or seat adjustments.
• Do not leave children in the vehicle unatte nded, especially in hot weather when
the inside of the vehicle can get hot enough to kill them. They could also activate
vehicle controls causing it to move unexpectedly.1 Protecting Child Passengers
To deactivate a lockable retractor, release the buckle
and allow the seat belt to wind up all the way.
To remind you of the pa ssenger’s front airbag
hazards and child safety, your vehicle has warning
labels on the dashboard (U.S. models) and on the
front visors. Please read and follow the instructions
on these labels. 2 Safety Labels P. 76
3WARNING
Allowing a child to play with a seat belt or
wrap one around their neck can result in
serious injury or death.
Instruct children not to play with any seat
belt and make sure any unused seat belt a
child can reach is buckled, fully retracted,
and locked.
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uuChild Safety uSafety of Infants and Small Children
Safe Driving
Safety of Infants and Small Children
An infant must be properly restrained in a rear-facing child seat until the infant
reaches the seat manufacturer’s weig ht or height limit for the seat.
■Positioning a rear-facing child seat
Child seats must be placed and secured in a
rear seating position.
When properly installed, a rear-facing child seat may prevent the driver or a front
passenger from moving their seat all the way back, or from locking their seat-back
in the desired position. Make sure that th ere is no contact between the child seat
and the seat in front of it.
It can also interfere with pr oper operation of the passenger’s advanced front airbag
system.
2 Airbags P. 46
If this occurs, we recommend that you install the child seat directly behind the front
passenger’s seat, move the seat as far fo rward as needed, and leave it unoccupied.
Or, you may wish to get a sm aller rear-facing child seat.
■Protecting Infants1Protecting Infants
Experts recommend use of a rear-facing seat for a
child so long as the child’ s height and weight are
appropriate for a rear-facing seat.
Infants should never be s eated in a forward-facing
position.
Always refer to the child seat manufacturer’s
instructions before installation.
Do not allow a front seat to rest against a child seat
installed in a rear seating position:
The weight sensor in the fr ont seat may not correctly
detect the actual weight of the occupant.
3WARNING
Placing a rear-facing child seat in the front
seat can result in serious injury or death
during a crash.
Always place a rear-fac ing child seat in the
rear seat, not the front.
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