2023 HONDA CIVIC radiator

707Continued
Maintenance
Maintenance Under the Hood
Maintenance Items Under the Hood
1.5 L engine models
Brake/Clutch* Fluid
(Black Cap)
Radiator Cap Washer Fluid
(Blue Cap)
Engine Oil Dipstick
(Orange) Engine Oil Fill Cap Battery
Engine Coolant
Reserve Tank
* Not available on all models
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708
uuMaintenance Under the Hood uMaintenance Items Under the Hood
Maintenance
2.0 L engine models with Auto Idle Stop
Brake/Clutch*
Fluid (Black Cap)
Washer Fluid
(Blue Cap) Engine Oil Dipstick
(Orange)
Battery
Radiator Cap
Engine Coolant
Reserve Tank Engine Oil Fill Cap
* Not available on all models
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721
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 first. If it is completely empty, also check the coolant level in the
radiator. 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
■Reserve Tank
Models with Auto Idle Stop
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 radiator 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 radiator cap.
MAX
MIN
Reserve Tank
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uuMaintenance Under the Hood uEngine Coolant
722
Maintenance
1. Make sure the engine and radiator are
cool.
2. Turn the radiator cap 1/8 turn counter-
clockwise and relieve any pressure in the
cooling system.
3. Push down and turn the radiator cap
counter-clockwise to remove it.
4. The coolant level should be up to the base
of the filler neck. Add coolant if it is low.
5. Put the radiator cap back on, and tighten it
fully.
■Radiator1Engine 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 Radiator
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.
Radiator Cap
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723
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
Models without Auto Idle Stop
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
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uuMaintenance Under the Hood uEngine Coolant
724
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
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uuOverheating uHow to Handle Overheating
792
Handling the Unexpected
■Next thing to do
1.Check that the cooling fan is operating and
stop the engine once the Engine
temperature too hot. Do not drive.
Allow engine to cool. message on the
driver information interface disappears.
u If the cooling fan is not operating,
immediately stop the engine.
2. Once the engine has cooled down, inspect
the coolant level an d 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 coolan t 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, re start it and check the driver information
interface.
If the Engine temperature too hot. Do not drive. Allow engine to cool.
message does not appear, resume driving. If it appears again, contact a dealer for
repairs.
1 How to Handle Overheating
If the coolant is leaking, contact a dealer for repairs.
Use water as an emergency/temporary measure only.
Have a dealer flush the system with proper antifreeze
as soon as possible.
3WARNING
Removing the radiator 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 radiator cap.
MAX
Reserve Tank
MIN
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uuOverheating uHow to Handle Overheating
794
Handling the Unexpected
■Next thing to do
1.Check that the cooling fan is operating and
stop the engine once the temperature
gauge goes down.
u If the cooling fan is not operating,
immediately stop the engine.
2. Once the engine has cooled down, inspect
the coolant level an d 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 coolan t in the reserve tank,
check that the radiator is cool. Cover the
reserve tank 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 has gone down, re sume 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 emergency/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.MAX
Reserve Tank
MIN
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