2000 HONDA CIVIC heater

Connector ldentification and Wire Harness Routing
D
How to ldentify Connectors:
ldentification numbers have been assigned to all connectors. The number is preceded by the letter "C" for connectors,"G" for ground terminals or "T" for non-ground terminals.
Location
HarnessEngine CompartmentDashboardOthers {Floor, Door,
Trunk/Hatch, and Rootl
Starter cablesT1, T2 and @
Battery ground cableG1 and O
Engine ground cable AT3
G2
Engine ground cable BT4
Under-hood ABS fuse/relay box wire
harness (With ABS)
t5 ano (9
Engine wire harnessCl01 thru C147
T101 and T102
G101
Engine compartmenl ware harnessC201 thru C215
G201 and G202
Main wire harnessC301 thru C310
C351 thru C361
C401 thru C452
G401 and G402
Dashboard wire harnessC501 thru C520
G501
FIoor wire harnessC551 thru C573
G551 and G552
Rear wire harnessC601 thru C62l
G601 and G602
Driver's door wire harnessC631 thru C640
Passenger's door wire harnessC651 thru C657
Left rear door wire harness (Sedan)C661 thru C664
Right rear door wire harness (Sedan)C671 thru C674
Roof wire harness (Without moonroof)C701 thru C719
Moonroof wire harness {With moon-
roof)
C7l'l thru C719
Heater sub-harness AC721 thru C729
Heater sub-harness BC7 41 thtu C7 44
Ay'C wire harnessC751 thru C754
G751
Hatch wire harness (Hatchback)C761 thru C768
Rear window defogger grgund wirec771
G171
Secondary heated orygen sensor sub-
narness
C781 and C782
Fuel tank pressure sensor sub-harnessC791 thru C793
SRS main harnessC801 thru C807
G801
Rear window defogger wireC831 thru C833

Gonnector ldentification and Wire Harness Routing
Msin Wire Harness (Right side oI dash branch)
Connector or
Terminal
Number of
CavitiesLocationConnects toNotes
c440
c441
c442
c443
c4M
c445
c446
c452
16
2
20
7
22
22
Under middle of dash
Under right side of dash
Under right side of dash
Under right side of dash
Behind right side of kick panel
Behind right side of kick panel
Under right side of dash
Under right side of dash
Heater sub-harness A (C721)
Service check connector
Junction connector
PGM-Fl main relay
ABS control unit
ABS control unit
Engine wire harness (C131)
ECM/PCM
G402Right kick panelBody ground, via main wire harness
*'l: '99 - 00 models
23-38

Gonnector ldentification and Wire Harness Routing
Heater Sub-harness A: '96 - 98 models
Connector or
Terminal
Number ot
CavitiesLocationConneqts toNotes
c7 21
c722
c723
c724
c727
7
20
2
Under left side of dash
Behind glove box
Behind glove box
Behind glove box
Behind glove box
Behind glove box
Behind glove box
Main wire harness (C440)
Mode control motor
Heater sub-harness B 1C741)Ay'C thermostat
Blower motor
Blower resister
Recirculation control motor
Heater Sub-harness B: '96 - 98 mod€ls
HEATER SUB.HARNESS A
Connoctor 01
Terminal
Number of
CavitiesLocationConngcts loNotes
c7 41
c142
c7 43
20
14
Behind glove box
Behind middle of dash
Behind middle of dash
Heater sub-harness A (C723)
Heater fan switch
Heater control panel
23-58
HEATER SUB-HARNESS B

'
Heater Sub-harness A: '99 - 00 models
Connector or
Terminal
Number of
CavitiesLocationConnects toNotes
c721
c722
c723
c724
c725
c726
c727
c728
c729
c730
7
24
3
2
4
1
5
4
Under left side of dash
Behind glove box
Behind glove box
Behind glove box
Behind glove box
Behind glove box
Behind glove box
Behind glove box
Behind glove box
Behind glove box
Main wire harness (C440)
Mode control motor
Heater sub-harness B (C741)
lilc thermostat
Blower motor
Power transistor
Recircuiation control motor
Heater sub-harness B (C744)
Air mix control motor
Blower motor high relaY
Heater Sub-harness B: '99 - 00 models
HEATER SUB.HARNESS A
Connector or
Terminal
Number of
CavitiesLocationConnects toNotes
c7 41
c'742
c143
c744
20
8
20
1
Behind glove box
Behind middie of dash
Behind middle of dash
Behind glove box
Heater sub-harness A (C723)
Heater control Panel
Heater control Panel
Heater sub-harness A (C728)

'99 - 00 models
IGNITONSWTCH
-fO Ctsr
\j7 |
I
I
WHT/BLK +WHT
HEATERPUSHswtTcH
BLK
G40lG402
BLK
G401G402
UNDER HOOD FUSEi RELAY BOX
No 4r (80A) No 42 (40A)
8
CLIMATE CONTROLUNIT/ R€ar window delogg€t \I I mer orcLril blill nlo J\climale conlro unil /
I{/\A-4<-INDICATOS(LE0)
II REAF WINDOWDEFOGGEBswtTcH7 16
,ll
23-203
l-

Contents
How to Use This Manual ICircuit Schematics (see Circuit Index)Fuse/Relaylnformation 6Ground-to-Componentslndex 6-6ComponentLocationPhotooraohs 201Conriector Views 202
Circuit Index
Accessory power socket 155Air conditionerAir delivery'96198 models 61'99-'00 models 61-2Blower controls'96198 models 60'99100 models 60-1Compressor controls 62Fans 63Anti-lock brake system (ABS) 44A/T gear position indicatorCVT 89All except CVT 89-1Automatic transmission controlsAll '96-'98 models except CVT and GX 39All '99100 models except CVT 39-8All GX models 39-8'96-'98 CVT 39-4'99100 cw 39-12Back-up lightsCoupe and Sedan 110Hatchback l'10-1Brake lightsAll Coupes and'96-'98 Sedans 110-15'99-'00 Sedans 110-16Hatchback 110-17Brake system indicator light'96198 models 7'1'99100 models 71-1Ceiling light 114-3Charging system 22Condenser fan 63Console lights 114Cruise control 34Dash lights 114Daytime running lights 110- 13Engine coolant temperature gauge 81-1Fog lights 110-10Front parking lights 110-2Fuel gauge 81-1Fuse/relay boxUnder-dash 6Under-hood 6-4Underhood ABS 6-3Gauges 81Ground distribution 14Ground-to-Componentslndex 6-6Hazard warning lightsAll except '99100 Sedans 110-6'99100 Sedans 110-8Headlights 110-12Headlight switch 100Heater - See Air ConditionerHorn'96197 models 40'98 model 40-1'99100 models 40-2lgnition key reminder 73lgnition systemAll '96198 models except Dl685 20All '99100 models except D16Y5 with Mn 2O-2All D1685 engines 20-2'99-'00 D 16Y5 with M/T 20
lndicators 80Integrated control unit 70lnterlock systemAll except'96J98 CVT 138'96198CVT 138-1License plate lightsAll Coupes and '96-'98 Sedans I l0-3'99100 Sedans 1 10-4Hatchback 110-5Low fuel indicator light 74Moonrool'96197 models |22'98-'00 models 122-1Odometer 81Oil pressure indicator light 80-3Power distributionBattery to ignition switch, fuses, and relaysFuses to relays and components 10-2Power door locksAll models without keyless entry 130'96-'98 models with keyless entry 130-2'99100 models with keyless entry 130-12Power mirrorsWithout detogger 141With defogger '141-2
Power windows 120Programmed fuel injection system (PGNr-Fl)All '96-98 models except D1685 23All '99-'00 models except D16Y5with M/T and D1685 24All D1685 engines 25'99100 D16Y5 with M/T 23Radiator fan 63Rear window defogger'96-,98 models 64'99100 models 64-1Seat belt reminder 73Security system'96.'98 USA HX, LX, EX 133'96-'98 Canada EX, Si 133'99TOO USA HX, LX, EX, DX.V Si 133-4'99100 Canada EX, Si 133-4All CX and DX models 133-8Speedometer 81Starting systemA./T (All except Dl685) 21A"/r (D16Bs) 21-1Manualtransmission 21-2Slereo sound system 150Supplemental rastraint system (SRS) 47Tachometer 81TailliqhtsAllboupes and'96-'98 Sedans 110-3'99100 Sedans 1 10-4Hatchback 110-5Trunk light 114-3Turn signal lightsAll except'99100 Sedans 110-6'99-'00 Sedans 1 10-8Vehicle speed sensor (VSS) 33Wiper/washerFront 91Rear 92
10

Ground Distribution Schematics
This sample Ground Distribution schematic shows all of the components that share two
ground points.
TCSCONTROLUNITPage 35
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FRONTPASSENGER'SSEAT HEATERPage 147
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FRONTPASSENGER'SSEAT BELTSWITCHPage 145
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RIGHTREAR DOORASHTRAYLIGHTPage 114
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G601c611

Fuse
NumberAmpsPageFuse Name
(RR WIPER
RR WASHER)
i R HiL HIGH BEAM | 10
L H/L HIGH BEAM
| (PAIV RR-L)
i (P/vv RR-R)
(rGN CO|L)
10I (P,^/V AS)
Component or Circuit Protected
Not used
Not used
Rear wiper, Security system (option)
(Vehicles pre-wired for accessory security system)
'10r 1n-2
I
| 1 10-12i Right headlight, DRL control unit (Canada)
Lett headlight, DRL control unit (Canada)
I ro-rsSecurity system (option)
| 120-2 | Left rear window motor
Right rear window motor
lgnition coil ('98-'00 models except GX)
| 120-1 | Front passenger's window motor
i (PiW DH)| 20 1 12O I Driver's window motor
TURN LIGHTSHazard warning switch
FUEL PUMP
(SRS UNIT)
PGM-FI main relav, SRS unit
(cRUrsE CoNTROL)
/KtrVt trSS\
Stereo radio tuner ('96-'98 USA: LX, EX, and HX),
Cruise control main switch, Keyless door lock
control unit ('99-'00 models with keyless entry)
15ALTERNATOR
SP SENSOR
l-a10-4I ELD unit, Gauge assembly, TCM (96-'98 CW, PGM-FI
16I RR DEF RELAY7.510-8I Rear window defogger ('96-'98 models), ABS control
I unit. Power mirror switch ('99-'00 models except GX)
i-HEATER r/C
I RELAY
Power mirrors ('96-98 models and all GX models),
Air delivery, Blower controls, AilC compressor
controls, Fans
I (RUNNING LIGHT
I RELAY)
1 7.5 1
tl
I DRL control unit (Canada)
i BACK-UP LTGHTSi Back-up lights
(RUNNING LIGHT)DRL control unit (Canada)
I R H/L LOW BEAM'10 l11o-12Right headlight
I L H/L LOW BEAM | 101110-12 | Left headlight
(cont'd)
(SRS)SRS unit
6-1