2003 HONDA CIVIC fan

Cooling System
Component Location Index
WATER PUMPInspection, page 10-5Replacement. page 10-5
RESERVETANK
RADIATORCAP
RAOIATOR FAN SWITCHTest, page 10-17Replacement, page 10'17
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WATER OUTLET,Installation, page'10-g
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CONNECTING PIPE
WATER PASSAGEInstallation, page 10-9
THERMOSTATTest, page 10 4Replacement, page 10 8
RADIATORReplacement, page 10-'l0
RADIATOR FANASSEMgLYReplacement, page 10-10Fan MotorTest, page 10 4A/C CONDENSERFAN ASSEMBLYReplacement, page 10 10Fan Motor Test, page '10-4
10-2
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Cooling System
Fan Motor Test
1. Disconnect the 2P connectors from the radiator fan
motor and condenser fan motor.
Test the motor by connecting battery power to the
B terminal and ground to the A terminal.
lf the motor fails to run or does not run smoothly,
reptace rL
10-4
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Thermostat Test
Replace the thermostat if it is open at room
remperalure.
To test a closed thermostatl
1. Suspend the thermostat (A) in a container of water.
Do not let the thermometer {B) touch the bottom of
the hot container.
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2.
3.
Heat the water, and check the temDerature with a
thermometer. Check the temperature at which the
thermostat first opens, and at which it is fully open.
Measure the lift height of the thermostat when it is
fullv ooen.
STANDARD THERMOSTAT
Lift height; above 8.0 mm (0.31 in.)
Starts opening: 169 176"F(76 80"C)
Fully open: 194"F {90'Cl
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1.
After the coolant has drained, tighten the radiator
drain plug securely. and installthe reserve tank
drain cap securely.
Fill the reserve tank to the MAX mark (A) with
Honda All Season Antifreeze/Coolant Tvpe 2
(P/N O1999-9001).
8. Pour Honda All Season Antifreeze/Coolant Type 2
into the radiator up to the base of the filler neck.
NOTE:. Always use Honda All Season Antifreeze/Coolant
Type 2 {P/N 01999-9001). Using a non-Honda
coolant can result in corrosion, causing the
cooling system to malfunction or fail.. Honda All Season Antifreeze/Coolant Type 2 is a
mixture of 50% antifreeze and 507o water. Pre-
mixing is not required.
Engine Coolant Refill Capacity including the
reserve tank capacity of 0.53 4 (0.56 US gtl :
5.0 0 (s.3 US qt)
Installthe radiator cap loosely.
Start the engine, and let it run until it warms up (the
radiator fan comes on at least twice).
Turn off the engine. Check the level in the radiator,
and add Honda All Season Antifreeze/Coolant Type
2 if needed.
Put the radiator cap on tightly, then run the engine
again and check for leaks.
lnstall the splash shield (see step 22 on page 5-12).
10.
11.
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10-7

Cooling System
Radiator and Fans Replacement
1. Drain the engine coolant (see page 10-6).
2. Remove the front bumper {see page 20,85).
3. Remove the bulkhead.
4. Remove the upper radiator hose and lower radiator hose.
DRAIN PLUG
UPPER BADIATOR HOSE
BAOIATOA FANASSEMBLY
{
O.RINGRADIATOR CAP
BADIATOB
LOWERCUSHION
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RADIATOR FANswtTcH24Nm{2.1t kgl m. 17lbl hl
LOWER FADIATORHOSE
RESERVETANK
A/C CONDENSERFAN ASSEMBLY
9.8 N m {1.0 kgf m,7.2 lbf ft)CONNECTORSRADIATOB FAN SWITCHCONNECTOB
5. Disconnect the fan motor connectors and radiator fan switch connector, then pull the radiator up and out.
6. Remove the fan shroud assemblies and other parts from the radiator.
7. Installthe radiator in the reverse order of removal. Make sure the upper and lower cushions are set securelV.
8. Install the bulkhead in the reverse order of removal. Apply body paint to the bulkhead mounting bolts.
9. Fill the radiator with engine coolant and bleed the air (see page 10-6).
10-10
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Fan Controls
Component Location Index
RADIATOR FAN RELAY
RADIATOB FAN SWITCHTest, page 10'17Replacement, page'10-17
UNDER.HOODFUSE/RELAY BOX
RADIATOR FAN ASSEMBLYMotor Test, page 10 4
CONDENSER FAN ASSEMBLYMotor Test, page 10-4
10-11

Fan Controls
Symptom Troubleshooting Index
Before performing any troubleshooting procedures check:. Fuses. Grounds. Cleanliness and tightness of all connectors
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\,4
SYMPTOMPROCEDURE
Radiator fan does not run at allRadiator Fan Circuil Troubleshooting (see page 1O-14).
Radiator fan does not run for engine cooling, but it runswith A,/C ON
Radiator Fan Switch Circuit Troubleshooting (Open)
(see page 10-16).
Radiator fan runs with ignition switch ON (ll), Ay'C OFF,
and engine temperature below 199"F (93"C)Radiator Fan Switch Circuit Troubleshooting (Short)
(see page 10-'16).
10-12
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Fan Gontrols
Radiator Fan Circuit Troubleshooting
1. Check the No. 4 (20A) fuse in the under-hood
fuse/relay box, and the No. 14 (10A) fuse in the
under-dash fuse/relay box.
ls the tuse (s) OK?
YES-Go to step 2.
NO- Replace the fuse (s) and recheck.l
2. Remove the radiator fan relay from the under-hood
fuse/relay box, and test it (see page 22-51).
ls the relay OK?
YES Go to step 3.
NO Replace the radiator fan relay. t
3. Measure the voltage between the No. 2 terminal of
the radiator fan relay 4P socket and body ground.
RADIATOR FAN RELAY 4P SOCKET
Terminal side of female terminals
ls there battery voltage?
YES Go to step 4.
NO Replace the under-hood fuse/relay box. I
10-14
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4. Connect the No. landNo.2terminalsofthe
radiator fan relay 4P socket with a jumper wire.
RADIATOR FAN RELAY 4P SOCKET
JUMPERWIRE
Terminal side of Iemale terminals
Does the radiatot fan run?
YES Go to step 5.
NO Go to step 6.
Disconnect the jumper, and turn the ignition switch
ON { ll}. Check for voltage between the No. 3
terminal of the radiator fan relay 4P socket and
body ground.
BADIATOB FAN RELAY 4P SOCKET
Termlnal side of female terminals
ls there battety voltage?
YES-Go to step 9.
NO Check for an open in the wire between the
under-hood fuse/relay box and under-dash fuse/
relay box.l
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7.
Disconnect the radiator fan motor 2P connector.
Check for continuity between the No. 1 terminal of
the radiator fan relay 4P socket and the No. 2
terminal of the radiator fan motor 2P connector.
RAOIATOR FAN REI-AY 4P SOCKET
Terminal side offemale terminals
RADIATOR FAN MOTOR 2P CONNECTOR
ls thete continuity?
YES-Go to step 8.
NO Repair open in the wire between the under-
hood fuse/relay box and the radiator fan motor 2P
connector terminal No. 2,I
8. Check for continuity between the No, 1terminal of
the radiator fan motor 2P connector and bodv
g rou nd.
RADIATOR F
Wire side of female terminals
ls there continuity?
YES Replace the radiator fan motor.l
NO Check for an open in the wire between
radiator fan motor 2P connector terminal No. 1 and
body ground. lf the wire is OK, check for a poor
ground at G301.1
AN MOTOR 2P CONNECTOR
rftr
T-
Y
9.
10.
Reinstall the radiator fan relay.
Disconnect the radiator fan switch 2P connector.
Connect the No. 1 and No. 2 terminals, of the
radiator fan switch 2P connector with a jumper wire.
RAOIATOR FAN SWITCH2P CONNECTOR
11.
5\- IJUMPERf-; 'fl I wrRE
--
Wire side of female terminals
Does the radiator fan run?
YES- Replace the radiator fan switch.l
NO-Go to step 12.
Remove the jumper wire, and measure the voltage
between the No, 2 terminal of the radiator fan
switch connector and body ground,
RADIATOR FAN SWITCH2P CONNECTOR
ls there battery voltage?
YES Check for an open in the wire between
radiator fan switch 2P connector terminal No. 1 and
body ground. lf the wire is OK, check for a poor
ground at G301.1
NO Repair open in the wire between the radiator
fan switch terminal No. 2 and the under-hood
fuse/relay box.l
10-15