2003 HONDA CIVIC %27

Heater Control Power and Ground Circuits Troubleshooting
1. Check the No.14 (10A)fuse in the under-dash
fuse/relay box.
ls the f use OK?
YES-Go to step 2.
NO-Replace the fuse, and recheck.l
2. Disconnect heater control panel connectorA{'14P).
3. Turn the ignition switch oN (ll).
4. Measure the voltage between the No. l4terminal
of heater control panel connector A (14P) and body
grouno.
HEATER CONTROL PANEL CONNECTOR A {14P}
23456
78I10 l,111214
Wire side of temale terminals
BLK/YEL
ls there battery voltage?
YES-Go to step 5.
NO Repair open in the wire betvveen the No. 14
fuse in the under-dash fuse/relay box and the
heater control panel.l
Turn the ignition switch OFF.
6. Check for continuity between the No. l3terminal of
heater control panel connector A (14P) and body
g rou nd.
HEATER CONTRoL PANEL CONNEcToR A (1ilP)
123456
I89r0 t,1l1214
BLK
.o
Wire side of temaleterminals
ls therc continuity?
YES Check for loose wires or poor connections at
healer control panel connector A (14P). lfthe
connections are good, substitute a known-good
heater control panel, and recheck. lf the symptom/
indication goes away, replace the original heater
control panel.l
NO Check for an open in the wire between the
heater control panel and body ground. lf the wire is
OK, check for poor ground at G501. I
21-27

5. Connect the No. 1 and No. 2 terminals of the
compressor clutch relay 4P socket with a jumper
wire.
COMPRESSOR CLUTCH RELAY 4P SOCKET
JUMPER WIRE
Does the compressor clutch click ?
YES Go to step 6.
NO-Go to step 14.
6. Disconnect the jumper wire.
7. Turn the ignition switch ON (ll).
8. Measure the voltage between the No. 3 terminal of
the compressor clutch relay 4P socket and body
ground.
COMPRESSOR CLUTCH RELAY 4P SOCKET
ls there battery voltage?
YES-Go to step 9.
NO Repair open in the wire between the No.
fuse in the under-dash fuse/relay box and the
compressor clutch relay, I
14
L Turn the ignition switch OFF.
10. Reinstallthe compressor clutch relay.
1 1. l\4ake sure the Ay'C switch is OFF.
12. Turn the ignition switch ON {ll).
13. Uslng the Backprobe Set, measure the voltage
between the No. 18 termina! of ECI\4 connector
E {31P) and body ground with the ECM connectors
connected.
ECM CONNECTOR E 131P}
23t4561E9
141516m21
22232426272931
RED
Wire side of female terminals
ls there battery voltage?
YES Update the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good ECIM, replace the
original ECM.I
NO Repair open in the wire between the
compressor clutch relay and the ECM.I
14. Disconnect the jumper wire.
15. Disconnect the compressor clutch lPconnector.
{cont'd)
21-31

Heating and Air Gonditioning
1.
Compressor Clutch Check
Check the armature plate for discoloration, peeling,
or other damage. lf there is damage, replace the
clutch set (see page 21-49),
Check the rotor pulley bearing play and drag by
rotating the rotor pulley by hand. Beplace the
clutch set with a new one if it is noisy or has
excessive play/drag (see page 21-49).
Measure the clearance between the rotor pulley (A)
and the armature plate (B) all the way around. lf the
clearance is not within specified limits, remove the
armature plate (see page 21-49) and add or remove
shims as needed to increase or decrease clearance.
Clearance: 0.510.15 mm {0.02010.006 in.)
NOTE: The shims are available in four thicknesses:
0.1 mm.0.2 mm,0.4 mm, and 0.5 mm.
21-48
a
4. Release the field coil con nector f rom the holder,
then disconnect it. Check the thermal protector for
continuity. lf there is no continuity, replace the
thermal protector (see page 21-51).
NOTE: The thermal Drotector will have no
continuity above 252to270"F \122lo 132'C). When
the temperature drops below 241 to 219'F (116 to
104'C), the thermal protector will have continuity.
Check resistance of the field coil. lf resistance is not
within specifications, replace the field coil
(see page 21-49).
Field Coil Resistance: 3.05 3.35ohmsat68"F
t20"c)
,\.

Heating and Air Conditioning
System Evacuation
Use only service equipment that is U.L.-listed and is
certified to meet the requirements of SAE J2210 to
remove HFC-134a (R-134a)from the air conditioninq
system.
lf accidental system discharge occurs, ventilate the
work area before resuming service.
Additional health and safety information may be
obtained from the refrigerant and lubricant
manufacturers.
1. When an Ay'C system has been opened to the
atmosphere, such as during installation or repair, it
must be evacuated using a R-134a refrigerant
recovery/recycling/charging station (lf the system
has been open for several days, the receiver/dryer
should be replaced, and the system should be
evacuated for several hours.)
. Air conditioning refrigerant or lubricant vapor
can irritate your eyes, nose, or throat.. Be carefulwhen connecting service equipment.. Do not breathe refrigerant or vapor.
21-54
2. Connect a R-134a refrigerant recovery/recycling/
charging station (A)to the high-pressure servicepon (B) and the low-pressure service port (C), as
shown, following the equipment manufacturer's
instructions. Evacuate the system.
lf the low-pressure does not reach more than 93.3
kPa {700 mmHg, 27.6 in.Hg) in 15 minutes, there isprobably a leak in the system. Partially charge the
system, and check for leaks (see step 3 on page 21-
56).
-i - r4.t

Connectors and Harnesses
Engine Wire Harness
Camshaft position (CMP) sensorLllr sensorEC[,4 connector AECI/l connector BEngine coolant temperature (ECT)
sensorEngine oil pressure switchEVAP canister purge valveldle air control (lAC)valve
lgnition coil No. llgnition coil No. 2lgnition coil No. 3lgnition coil No. 4Iniector No. 1Inlector No.2Iniector No.3Iniector No. 4Intake air temperature {lAT) sensor
TDC sensorThrottle position (TP) sensorVehicle speed sensor (VSSI
VTC oil control solenoid valveVTEC oil pressure switchVTEC solenoid valvec 101
c102
233
242
Transmission housingLeft side of engineRight side ofengineUnder glove boxUnder glove boxLeft side of engine
Bight side oI engineLeft side of intake manifoldLeft side of intake manifoldMiddle of engine compartmentMiddle of engine compartmentMiddle of engine compartmentMiddle of engine compartmentMiddle of engine compartmentMiddle of engine compartmentMiddle of engine compartmentMiddle of engine companment
28
1845672524201912
811102729303
22
12333332222233
322220
Left side of intake manifoldLeft side of engineLeft side of intake manifoldTransmission housingRight side o{ engineRight side of engineRight side of engineUnder right side of dash
Front of engine companment
Front of engine compartment
ECM wire harness {see page22-321Starter subharness (see page22-15)Starter subharness (see page22 151
Connector to Harness Index (cont'dl
22-16

Connectors and Harnesses
Dashboard Wire Harness A {Left branchl
Connector or TerminalffiAccessory power socketAudio antennaBrake pedal position switchClutch interlock switchClutch pedal poistion switchCruise control unitCruise main switchDaytime r!nning lights control unitDaytime running lights relayGauge assembly connector AGauge assembly connector BHazard warning switchHeater control panel connector AHeater control panel connector BHVAC push switch assemblyKeyless receiver unitLow beam cut relayOptional security connectorPower mirror switchUnder-dash fuse/relay boxconnector K (see page 22-45)Under'dash fuse/relay box
L {see page 22-45}Underdash fuse/relay boxconnector M lsee page 22'45)Under-dash fuse/relay boxconnector N (see page 22-45)UndeFdash fuse/relay boxconnector O (see page 22-45)UndeFdash fuse/relay boxconnectorY (see page 22 45)c504
c505
c506
c507
c508
c509
c510
22226
3029628
I820111819105327
,I4
12
11
34
1
24
25
2 Under middle of dash2 Under left side of dash4 ] Under left side of dash2 ] Under left srde of dash2 | Under left side of dash14 I Under left side of dash5 Under left side of dash14 Under lett side of dash4 Under lett side of dash22 I Behind gauge assembly22 i Behind gauge assembly10 Behind hazard warnning switch22 Behind heater control panel'14 Behind heater control panel10 ] Behind HVAC switch assembly5 I Under middle of dash5 lUnderleftsideofdash16 Under lefr side of dash13 Under left side oI dash17 ln the under-dash fuse/relay box
CanadaCanada
l0In the under-dash fuse/relay box
In the undeFdash fuse/relay box
In the underdash fuse/relay box
In the under-dash fuse/relay box
In the under-dash fuse/relay box
Under left side of dash
Under left side ot dash
Under left side of dash
Under left side of dash
Under middle of dash
Under middle of dash
Under middle ol dash
Driver's door wire harness(see page 22'40)Driver's door wire harness(see page 22-40)Left side turo signal lightsuonarnessRoof wire harness (see page22 3AlFloor wire harness {see page22-341Floor wire harness (see page22 34JDashboard wire harness B(see oaoe 22-30)
12
12
G501
G503
1
21
Under gauge assembly
Under left side of dash
Body ground via dashboard
Body ground via dashboard
Left Side Turn Signal Light Sub harness
Connector to Harness Index (cont'd)
L
Connector or TerminalCavitiesLocationConnects toNolesLeft side turn signal lightc506353422Behind left side turn signal lightUnder left side of dashDashboard wire harness A
22-26

DASHBOARD WIREHARNESS A
,./
-19
20
34 I
LEFT SIDE TURN SIGNAL LIGHTSUB HARNESS). \'u2s )t
30
(cont'd)
22-27

Gonnectors and Harnesses
a
Floor Wire Harness {Rear side}(cont'dl
Cargo areaDriver's door switchEVAP emission bypass solenoid valveEVAP emission control canister ventshut valveFuel pump/sending unitFuel tank pressure sensorLeft back-up lightLeft rear ABS wheel sensorLeft rear side marker lightLeft rear speakerLeft rear turn signal lightLeft side seat belt tensionerLeft taillighVbrake lightNoise condenser (rear windowdefogger)Noise condenser (rear window wiper)Passenger's door switchRear window wiper intermiftentcontrolunitRight back-up lightRight taillighvbrake tightRight rear turn signal lightBight rear ABS wheel sensorRight rear side marker lightRight rear speakerRight side seat belt tensioner
c554
Fueltank
FueltankFueltankLeft taillightLeft rear offloorBehind left side of rear bumperLeft quarter panelLefttaillightLeft B-pillarLeft taillightRight quarter panel
Right quarter panelRight B pillarRight q uarter panel
Right tai ightRight taillightRight taillightRight side of cargo area
side of cargo areaLeft B pillarFueltank
Right quaner panel
6224
I32512642A527'13
181011
222021151912117
I
2122
5322222232
232222212
12
2120
Behind right side of rear bumperRight quaner panelRight B-pillarRight quaner panelHatch wire harness (see page22 39)Hatch wire harness (see page
rear seal bdcl Bodv ground vta
Right side of cargo area Body ground via floor wire
Connector to Harness Index (cont'dl
22-36