2003 HONDA CIVIC 10-1

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

Fan Controls
Radiator Fan Switch Circuit
Troubleshooting (Openl
1. Disconnect the radiator fan switch 2P connector.
2. Turn the ignition switch ON (ll).
3. Measure voltage between the No.2 terminal ofthe
radiator fan switch 2P connector and body ground.
RADIATOR FAN SWITCH 2PCONNECTOR
ls there battety voltage?
YES-Go to step 4.
NO- Repair open in the wire between the radiator
fan switch 2P connector terminal No. 2 and under-
hood fuse/relay box.l
Turn the ignition switch OFF, and check for
continuity between the No. '1 terminal of the
radiator fan switch 2P connector and body ground.
RADIATOB FAN SWITCX 2PCONNECTOR
ls there continuity?
YES Replace the radiator fan switch. t
NO Check for an open in the wire between theradiator fan switch 2P connector terminal No. 1 and
body ground. lf the wire is OK, check for a poor
ground at G301.1
10-16
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Radiator Fan Switch Circuit
Troubleshooting (Short)
NOTE: After troubleshooting, perform the engine
control module (ECM)idle learn procedure (see page
1 1,139).
1. 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 2.
NO Replace the radiator fan relay.I
2. Remove the radiator fan switch, and test it (see
page 10-17 ).
Is the radiatot tan switch OK?
4.
YES Go to step 3.
NO Replace the radiator fan switch.I
Disconnect the battery negative cable from the
battery.
Disconnect engine control module {ECM) connector
B (24P) and the under hood fuse relay box 14P
connector.
Check for continuity between the No. 2 terminal of
the radiator fan switch 2P connector and bodygrouno.
RADIATOR FAN SWITCH2P CONNECTOR
lstnere continuity?
YES Repair short in the wire between the radiator
fan switch 2P connector terminal No. 2 and under-
hood fuse/relay box.l
NO Replace the under-hood fuse/relay box.t
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Radiator Fan Switch Test
NOTE: Bleed air from the cooling system after installing
the radiator fan switch (see page 10-6).
1, Remove the radiator fan switch from the radiator
(see page 10-17).
2. Suspend the radiator fan switch (A) inacontainer
of water as shown.
3. Heat the water, and check the temperature with a
thermometer. Do not let the thermometer (B) touch
the bottom of the hot conlainer.
4. Measure the continuity between terminal No. 1 and
terminal No. 2 according to the table.
Termina
Operation lTemperature1
swtTcH
ON196" 203'F(91" gs"C)
OFF5' 15'F {3' 8'C) lowelthan the temoeraturewhen it goes on
Radiator Fan Switch Replacement
1.Disconnect the radiator fan switch connector, then
remove the radiator fan switch (A).
A24 N m (2.4 kgt.m, 17 lbt.ftl
2. Installthe radiator fan switch with a new O-ring (B).
10-17

PGM-FI System
aDTG Troubleshootang (cont'dl
DTC P0128: Cooling System Malfunction
NOTE; lf the DTCS listed below are stored at the same
time as DTC P0128. troubleshoot those DTCS first, thenrecheck for P0128.
P0107, P0108, P1128, P1129: N4anifold absolutepressure (MAP) sensor
P] I06, P1 107, P1 108: Barometric pressure (BARO)
sensor
P1259: VTEC system
P01 16, P01 17, P01 18: Engine coolant temperature (ECT)
sensor
P01 12, P01 13: Intake air temperature (lAT) sensor
P0500: Vehicle speed sensor {VSS)P0335, P0336: Crankshaft position (CKP) sensor
P0300: Random misfire
P0301, P0302, P0303, P0304: No. 1, No. 2, No.3 or No.4
cylinder misfire
P0505: ldle control system malfunction
P1519: ldle air control (lAC)valve
DTC P0128 can occasionally set when the hood is
opened while the engine is running.
1. Check the engine coolant level
Is the engine coolant level low?
VES Refill the engine coolant. lf necessary, repair
the coolant leakage.l
NO Go to step 2.
2. Turn the ignition switch ON (ll), and make sure the
A,/C is off.
11-64
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3. Check the radiator fan.
Does the tadiator fan keep running?
YES Checkthe rad iato r fan circuit (see page 10-
14), the radiator fan switch circuit (Short) (see page
10-'16), and the radiator fan switch (see page 10-17).
Also, inspect the ECT and IAT circuits and terminal
connections. lf the circuits, the switch, and the
connections are OK, update the ECI\4 if it does not
have the latest software. or substitute a known-good ECM, then recheck (see page 1 1-6). lf the
symptom/indication goes away with a known-good
ECM, replace the original ECM.I
NO Replace the thermostat (see page 10-8).1

Compressor Replacement
1. lf the compressor is marginally operable, run the
engine at idle speed, and let the air conditioning
work for a few minutes, then shut the engine off.
2. Make sure you have the anti-theft code for the radio,
then write down the frequencies for the radio's
preset buttons.
3. Disconnect the negative cable from the battery.
4. Recover the refrigerant with a recovery/recycling/
charging station (see page 21-53).
5. Remove the alternator (see page 4-29).
6. Remove the Ay'C condenser fan assembly (see page
10-10).
7. Disconnectthe compressor clutch connector (A),
remove the bolts, then disconnect the suction line(B) and the discharge line (C)from the compressor.
Plug or cap the lines immediately after
disconnecting them to avoid moisture and dust
contamination.
6 x '1.0 mm9.8 N.m11.0 kgt.m,7.2 tbl.ttl
u1/
(
o
8. Remove the mounting bolts and the compressor.
8 x 1.25 mm22 N.m 12.2 kgf.m.
9. Installthe compressor in the reverse order of
removal, and note these items:
. Before installing the new compressor, check for
metal or other contamination in the line. Replace
any contaminated parts.. lf you're installing a newcompressor, you must
calculate the amount of refrigerant oil to be
removed from it (see page 21-6).. Replace the O-rings with new ones at each fitting,
and apply a thin coat of refrigerant oil before
installing them. Be sure to use the correct O-rings
for HFC-134a {R-134a) to avoid leakage,. Use refrigerant oil (KElHlN SP-'10) for HFC-134a
KEIHIN spiral type compressor only.. To avoid contaminatlon, do not return the oilto
the container once dispensed, and never mix it
with other refrigerant oils.. lmmediately after using the oil, reinstallthe cap
on the container, and seal it to avoid moisture
absorption.. Do not spill the refrigerant oil on the vehicle; it
may damage the paint. lf the refrlgerant oil
contacts the paint, wash it off immediately.. Charge the system (see page 21-55).. Do the engine control module (ECM) idle learn
procedure (see page 11-'139).. Enter the antitheft code for the radio, then enter
the customer's radio station presets.
21-47

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DTCDetection ltemNotes9-1Internal failure of the SRS unit. lf intermittent, it could mean internalfailure of the unit or a faulty indicator circuit. Refer toTroubleshooting Intermittent Failures (see page 23-26).
NOTE: Before troubleshooting DTC 9-1 or 9-2, check battery/systemvoltage. lf the voltage is low, repair the charging system beforetroubleshooting the SRS.
(see page 23-69)
9-2Internal failure of the SRS unit. lf intermittent, it could mean internalfailu re of the power supply (VB line). Refer to TroubleshootingIntermittent Failures (see page 23-26).
NOTE: Before troubleshooting DTC 9-1 or 9-2, check battery/systemvoltage. lf the voltage is low, repair the charging system or replacethe b€ttery before troubleshooting the SRS.
9-3Faulty driver's seat belt buckle switch(see Daqe 23-71)9-4
9-6
FaultLtglt passenger's seat belt buckle switch
Faulty Ieft front imDact sensorlgqgfage 23-74)
{see Daqe 23-77)9-7Faulty right front impact sensor(see paqe 23-79)10-1Seat belt and seat belt buckle tensioners (and airbag(s)) deployedDriver's side airbag deployed
Seat belt and seat belt buckle tensioners (and airbag(s)) and driver'sside airbag deployed
Front passenqer's side airbao deDloved
(see page 23-69)10-2
r0-3
'10-4
'10-5Seat belt and seat belt buckle tensioners (and airbag(s)) and frontpassenqer's side airbaq deDloved
10-6Driver's and front passenqer's side al10-7Seat belt and seat belt buckle tensioners (and airbag(s)) and driver'sand front passenger's side airbags deployed
1 1-1Open or increased resistance in driver's side airbao inflator(see paqe 23-81)Short to another wire or decreased resistance in driver's side airbaoinflator
(see page 23-82)
11-4Short to power in driver's side airbaq inflator(see oaqe 23-83)I t-5Short to ground in driver's side airbaq inflator{see paqe 23-85)Open or increased resistance in front passenger's side airbaginflator
(see page 23-86)
Short to another wire or decreased resistance in front passenger's
side airbag inflator
(see page 23-87)
12-4Short to power in front passenqer's side airbaq inflator{see Daqe zJ-uu}I z-5Short to ground in front passenger's side airbaq inflator(see oaqe 23-90)13-1Internal failure of the driver's side impact sensor(see page 23-70)
No signal from the driver's side impact sensor(see paqe 23-91)13-4
14-1-7ii,
Faulty power supply to the df,rglllug t Opact s9I99LInternal failure ofthe front passenger's side impact sensor
(see page 23-92)(see page 23-70)
14-3No signal from the front passenger's side impact sensor(see paqe 23-94)14-4Faulty power supply to the front passenqer's side impact sensor(see page 23-95)15-1Faultv OPDS unit or OPDS not initialized(see paqe 23-96115-2Faulty side airbag cutoff indicator circuit(see Daqe 23-99)15-3Faulty OPDS sensor(see oaoe 23-104)
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23-29

I
DTC s-1, 5-2, 5-4, s-8, 6-3, 6-4,6-7,6-8,7-1,
7-2,7-3, A-1,4-2, 8-3, 8-4, 8-5, 8-6, 9-1, 9-2:
Internal Failure of the SRS Unit
NOTE: Before troubleshooting any of these DTCs, check
the battery/system voltage. lf the voltage is low, repair
the charging system or replace the battery before
troubleshooting the SRS. lf the battery/system voltage
is now OK, ask the customer if the battery ever went
oeao,
1. Erase the DTC memory (see page 23-26).
2. Turn the ignition switch ON (ll), and check that the
SRS indicator comes on for about 6 seconds and
then goes off.
Does the SRS indicatot stay on?
YES Replace the SRS unit (see page 23-122).1
NO Intermittent failure, system is OK at this time.
Go to Troubleshooting lntermittent Failures (see
page 23-26).
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DTC 10-1, 10-2, 10-3, 10-4, 10-s, 10-6, 10-7:
Airbags, Side Airbags, and/or Seat Belt and
Seat Belt Buckle Tensioners Deployed
The SRS unit must be replaced after any airbags and/or
tensioners have deployed (see page 23-122). !
23-69