2021 HONDA CIVIC HATCHBACK cooling

uuClimate Control System uUsing Automatic Climate Control
218
Controls
Use the system when the engine is running.
1. Press the AUTO button.
2. Adjust the interior temperature us ing the temperature control dial.
3. Press the (ON/OFF) button to cancel.
1Using Automatic Climate Control
Pressing the button switches the climate control
system between on and off. When turned on, the
system returns to your last selection.
While ECON mode is active, the climate control
system may have reduced cooling performance.
Press the CLIMATE button to display A/C, MODE,
fan control information on the audio/information
screen to operate manually. Select ic on to turn on or
off A/C , change the vent mode , or change the fan
speed.
Models with ECON button
Models with Display Audio
Models with Display Audio
Models without SYNC button
A/C (Air Conditioning) Icon
Fan Control Icon
Temperature
Control Dial
AUTO Button
(Recirculation) Button
(CLIMATE)
Button
Fan Control
Dial
(ON/OFF) Button
(Fresh Air) Button
MODE Control
Icon
(Floor vents)
MODE Control
Icon
(Dashboard vents) MODE Control Icon
(Floor and
defroster vents)
MODE Control Icon
(Dashboard and
floor vents)
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４８分

589
uuMaintenance Under the Hood uEngine Coolant
Continued
Maintenance
Engine Coolant
This coolant is premixed with 50% an tifreeze and 50% water. Do not add any
straight antifreeze or water.
We recommend you check the engine coolant level every time you refuel. Check the
reserve tank. Add the engine coolant accordingly.
1. Make sure the engine and radiator are cool.
2. Check the amount of coolant in the reserve
tank.
u If the coolant level is below the MIN
mark, add the specified coolant until it
reaches the MAX mark.
3. Inspect the cooling system for leaks.
Specified coolant: Ho nda Long Life Antifreeze/Coolant Type 2
■Checking the Coolant
1Engine Coolant
NOTICE
Genuine Honda engine coolan t is a 50/50 mixture of
antifreeze and water that can withstand freezing at
temperatures as low as about −31°F (−35°C). If your
vehicle is consistently subjected to temperatures
below this, the concentration of antifreeze in the
coolant should be increased. Consult a dealer for
details.
If Honda antifreeze /coolant is not available, you may
use another major brand of non-silicate coolant as a
temporary replacement. Check that it is a high quality
coolant recommended for aluminum engines.
Continued use of any non-Honda coolant can result
in corrosion, causing the cooling system to
malfunction or fail. Have the cooling system flushed
and refilled with Honda anti freeze/coolant as soon as
possible.
3WARNING
Removing the reserve tank cap while the
engine is hot can cause the coolant to spray
out, seriously scalding you.
Always let the engine and radiator cool
down before removing the reserve tank
cap.
Reserve Tank
1.5 L engine models
2.0 L engine models
Reserve Tank
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uuMaintenance Under the Hood uEngine Coolant
590
Maintenance
1. Make sure the engine and radiator are
cool.
2. Turn the reserve tank cap 1/8 turn counter-
clockwise and relieve any pressure in the
cooling system.
3. Push down and turn the reserve tank cap
counter-clockwise to remove it.
4. Pour coolant into the reserve tank until it
reaches the MAX mark.
5. Put the reserve tank cap back on, and
tighten it fully.
■Adding the Coolant1Engine Coolant
Do not add rust inhibitors or other additives to your
vehicle’s cooling system. Th ey may not be compatible
with the coolant or with the engine components.
1 Adding the Coolant
NOTICE
Pour the fluid slowly and ca refully so you do not spill
any. Clean up any spills immediately; they can
damage components in the engine compartment.
Reserve Tank Cap
1.5 L engine models
2.0 L engine models
Reserve Tank Cap
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624
Maintenance
Climate Control System Maintenance
Air Conditioning
To ensure proper and safe operation, th e Society of Automotive Engineers (SAE
J2845) recommends that the refrigerant sy stem only be serviced by trained and
certified technicians.
Never repair or replace the air conditioning evaporator (cooling coil) with one
removed from a used or salvaged vehicle.
New replacement mobile air conditioning evaporators must be certified (and
labeled) as meeting SAE Standard J2842.
Dust and Pollen Filter
The climate control system is equipped wi th a dust and pollen filter that collects
pollen, dust, and other debris in the air. The Maintenance MinderTM messages will let
you know when to replace the filter.
We recommend that you replace the dust and pollen filter sooner when using your
vehicle in areas with high concentrations of dust.
1Climate Control System Maintenance
NOTICE
Vented refrigerant is harmful to the environment.
To avoid refrigerant from venting, never replace the
evaporator with one re moved from a used or
salvaged vehicle.
Refrigerant in your vehicle’ s air conditioning system is
flammable and can be igni ted during servicing if
proper procedures are not followed.
The air conditioner labe l is found under the hood:
2 Safety Labels P. 80
2 Specifications P. 684
Canadian models
: Caution
: Flammable
Refrigerant
: Requires Registered
Technician to Service
: Air Conditioning
System
1Dust and Pollen Filter
If the airflow from the climate control system
deteriorates noticeably, and the windows fog up
easily, the filter may need to be replaced. Please
contact a dealer for replacement.
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667
uuOverheating uHow to Handle Overheating
Handling the Unexpected
■Next thing to do
1.Check that the cooling fan is operating and
stop the engine once the Stop Driving
When Safe. Engine Temperature Too
Hot message on the driver information
interface goes off.
u If the cooling fan is not operating,
immediately stop the engine.
2. Once the engine has cooled down, inspect
the coolant level and check the cooling
system components for leaks.
u If the coolant level in the reserve tank is
low, add coolant until it reaches the MAX
mark.
u If there is no coolant in the reserve tank,
check that the radiator is cool. Cover the
radiator cap with a heavy cloth and open
the cap. If necessary, add coolant up to
the base of the filler neck, and put the
cap back on.
■Last thing to do
Once the engine has cooled sufficiently, restart it and check the temperature gauge.
If the temperature gauge pointer has gone down, resume driving. If it has not gone
down, contact a dealer for repairs.
1 How to Handle Overheating
If the coolant is leaking, contact a dealer for repairs.
Use water as an emergen cy/temporary measure only.
Have a dealer flush the system with proper antifreeze
as soon as possible.
3WARNING
Removing the reserve tank cap while the
engine is hot can cause the coolant to spray
out, seriously scalding you.
Always let the engine and radiator cool
down before removing the reserve tank
cap.
Reserve Tank
1.5 L engine models
2.0 L engine models
Reserve Tank
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675
uuFuses uFuse Locations
Continued
Handling the Unexpected
■Circuit protected and fuse rating
Circuit ProtectedAmps
1
Option Block 1*(60 A)
−−
Cooling Fan50 A*4
30 A*5
Audio AMP*(30 A)
IG Main 2*1(30 A)
Headlight High Beam Main30 A
Battery125 A
2
EPS70 A
IG Main 1 30 A*1
50 A*2
Fuse Box Option*(40 A)
Fuse Box 1 60 A
Front Wiper Motor30 A
Headlight Low Beam Main 30 A
3
Rear Defroster40 A
Starter Motor(30 A)
Fuse Box 240 A
ABS/VSA Motor40 A
ABS/VSA FSR40 A
Blower Motor40 A
4 −−
−−
−−
−−
5Cooling Fan*4(5 A)
6Washer 15A
7FI Main15 A*4
20 A*5
8 Stop Lights 10 A
9FI Sub15 A
10 Injector*4(15 A)
Sub Fan Motor*520 A
11LAF5A
12 FI ECU 10 A
13Hazard15 A
14 Rear Heated Seat*(15 A)
15IG Coil15 A
16 Transmission*3(15 A)
17Daytime Running Lights(10 A)
18 Back Up 10 A
19Audio(15 A)
20 Parking Lights 10 A
Circuit ProtectedAmps
*1:Models with smart entry system
*2:Models without smart entry system
*3:Continuously variable transmission models
*4:1.5 L engine models
*5:2.0 L engine models
21Interior Lights10 A
22 Front Fog Lights*(15 A)
23A/C Compressor10 A
24 Horn 10 A
25−−
26 Left Headlight Low Beam 10 A
27Right Headlight Low Beam10 A
28 − −
29Left Headlight High Beam10 A
30 Right Headlight High Beam 10 A
31Passenger’s Power Seat Sliding*(20 A)
32 Passenger’s Power Seat
Reclining
*(20 A)
Adaptive Damper System
*5(15 A)
33VB ACT(5 A)
Circuit ProtectedAmps
* Not available on all models
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