1998 HONDA CIVIC Heater motor

- How the Circuit Works
Battery voltage is supplied through tuse 56 to the
A,/C compressor clutch r€lay contacts at all times.
With the ignition switch in ON (ll), vollage is applied
to the coil of the A,/C compressor clutch relay
through fuse 17. When you push the A,/C switch
ON, and the heater fan switch is in position | , 2, 3,
or 4, a "ground" input is provided to the engine
control module (ECM) or powertrain control module
(PCM) through the l'lC thermostat and the l'lC
pressure switch.
The A,/C compressor clutch relay is grounded by the
engine control module (ECM) or powertrain control
module (PCM). When energized, the A'lC
compressor clutch relay allows battery voltage to
turn on the A,/C comDressor clutch.
The A,/C ON indicator light comes on when the A,/C
system is requested.
A,/C Thermostat
The A'lC thermostat is located on the evaoorator
housing. The A,/C thermostat turns off the A,/C
compressor clutch if the temperature at the
evaporator goes below 3'C (37'F). This prevents
condensation from freezing on the evaporator fins
and blocking the air delivery into the passenger
compartment. The blower motor will keep running
when the sensor turns off the comDressor.
A,/C Pressure Switch
The fuC oressure switch is located in the condenser
outlet line where refrigerant is in a high
temperature/high pressure liquid state. The switch
will sense abnormally high or low pressure, and
open the circuit. This removes ground, and the
compressor will stop running.
Thermal Protectot
The thermal protector, located on the A,/C
compressor, opens and turns the compressor off if it
senses high temperature. Once the compressor
cools, the switch will close and the compressor will
begin running again.
Refer to the Service Manual (Section 22,
Air Conditioning) for specific tests or
troubleshooting procedures.
62-3

- How the Circuit Works
Radiator Fan
Voltage is provided at all times to the radiator fan
relay (contacts) through fuse 57. With the ignition
swilch in ON (ll), voltage is provided to the coil of
the relay through luse 17.
The radiator tan relay can be grounded through
either the engine coolant temperature switch or the
engine control module (ECM) or powertrain control
module (PCM).
The engine coolant temperature switch grounds
the radiator fan relay (coil) when the engine
coolant temperature exceeds 199'F (83'C). The
switch opens when coolanl temperature
decreases 3'- 8'C.
Condenser Fan
Voltage is provided at all times to the condenser fan
relay (contacts) through fuse 56. With the ignition
switch in ON (ll), voltage is provided to the coil of
the relay through fuse 17. When you push the A'lC
switch and put the heater fan switch in 1, 2,3, o( 4
position, the ly'C thermostat comes on, the
condenser fan relay energizes, and the condenser
fan motor runs.
A,/C Thermostat
The A,/C thermostat is located on the evaporator
housing. The A,/C thermostat tums off the A/C
compressor clutch if the temperature at the
evaporator goes below 3'C (37'F). This prevents
condensation from freezing on the evaporator fins
and blocking the air delivery into the passenger
compartment. lf the temperature goes below 3'C
(37"F) tuming off the Ay'C thermostat, ground will be
removed from the condenser fan relay. This will
deenergize the relay and remove voltage from the
condenser fan motor causing the fan to stop running.
Reter to the Service Manual (Section 23, Eleckical)
for specific tests or troubleshooting procedures.
63-3

-
Component Connector View Index (Views begin on page 202-21
Connector View
ABS Control Unit........ ......63
Audio Unit ('99-'00 models) ......74
Combination Light Switch . . . . . . . . . . . . . . . 64
Combination Wiper Switch . . . . . . . . . . . . . . 65
Cruise Control Unit.... .....43
C\TTTransmission Solenoid ............. 25
Data Link Connector (DLC) ..... 48
Daytime Runnlng Lights Control Unit ..... 66
Engine control Module (ECM) ...........70
Exhaust Gas Recirculation (EGR) Valve
and Lift Sensor (D16Y5 Mfl, D1685) . . . . 10
Gauge Assembly .............71
HazardWarnlngSwitch,,. .,,,...,,,,... 32
Heater Control Panel ('96-'98 models) .....44
Heater Control Panel ('99-'00 models) ...., 76
Heater Fan Switch ('96-'98 models) ,,,.... 11
fniector Control Module (GX) ............77
I/
202-1
Connector View
Integrated Control Unit .......,. 67
f nterfock Control Unit .... ...... 26
Keyfess Door Lock Control Unit . . . . , . . . . . 75
Mode Control Motor ... ........'17
Moonroof Close Relay .. .......13
Moonroof Open Relay ... .......15
PGM-FI Main Relay .. .......... 18
Power Door Lock Conlrol Unil ..... ...... 37
Power Mirror Switch .,... ...... 33
Power Window Master Switch .,.........36
Powertrain Control Module (PCM) .......70
Security Control Unit ..., ..,,... 58
Security Starter Cut Belay ... ...,,,....,, 12
SRS Unit ............. 51
Stereo Radio Tuner ('96-'98 models) ...... 68
Transmission Control Module CICM) .....69

-17. Mode Control Motor
- Green- Behind dash, right of steering column- On heater sub-harness-A
1 BLK,TYEL (lgnition input)
2 YEUBLU (Detrost input)
3 YEL (H/DEF input)
4 BLUA/VHT (Heat input)
5 GRN/YEL (BI-LEV input)
YEURED (Vent input)'96.98: BLK (G402)'99-'00r BRNAVHT
{Motor ground input)
6
7
18. PGM-FI Main Relay
- Brown- Behind right side o{ dash- On main wire harness
'l
4
1 GRN/YEL(Fuel pump control)
2 BLUAVHT (Fuse 31)
3 BLK (G101)
*1: YEUGRN(Fuel pump output)*2: WHT/RED(Fuel supply control)
YEUGRN (Fuse 13)
YEUBLK (Power output)
WHT/BLK (Fuse 44)
6
7
*1= All except Dl685*2= D16Bs
19. Cl23 (D16Y5 M/T)
2
3
BLI(WHT
{Heater control)
BLK (Heater ground)
GRN/BLK(Sensor ground)
- cray- Right tront o{ engine- Connects engine wire harness to primary
HO2S pigtail
5
6
7
8
WHT (Hgater control)
WHT (Sensor input)
BLK (Sensor input)
RED (Sensor ground)
20. c136
- Gray- Left rear of engine compartment- Connects engine wire harness to main wire harness
'96198 D't6Y5:
1 Male - BLUAVHTFemale - BLU|/EL(A"/T controls)
2 GRN,^WHT (A,/T controls)
3 YEL (A/T controls)
4 GRN/YEL (A/T controls)
5 PN(BLK (fff gs6lrq;s;
6 PNI(BLU (A/T controls)
7 GRN/BLK (Ar/T controls)
8 RED/BLU (A/T controls)
9 WHT (A/T controls)
'96198 D16Y7/D16Y8:
GRN/BLK (A/T controls)
WHT/RED(lnterlock system)
10 WHT/RED (A"/T controls)
11 '98 models: GRN/BLK(PGr,4-Fr)
12 GRN (A/T controls)
13 l\4ale - REDMHTFemale - RED/BLU(4,/T controls)
14 N4ale - BLIVWHTFemale - ORN/BLU(A/T controls)
5 WHT (A/T controls)
6 BLU (Antf se11re;s;
7
A

01685:
3
1
2
3
4
5
6
7
8
BRN (PGM-FD
RED (PGIV-FD
BLU (PGI\4-FD
YEL (PGI,4,F|)
l\4ale - GFNFemale - WHT/RED(PGM-FD
GRN/BLK (A'tl gs6trels;
BLU (A/T controls)
wHT (A/I controls)
202-5

Connectol
or
Terminal
Number of
Cavities/
Color
LocationConnects toNotes
Connector ldentification and Wire Harness Routing
HEATER SUB.HARNESS A
1"t-
Heater Sub-harness A: '96-'98 models
c440
c722
c723
c724
c725
c726
c727
1 6-BLU
7.GRN
2O.GRY
3-GRY
2.NAT
4-BRN
4.GRN
Under middle of dash
Behind middle ot dash
Behind front console
Behind glove box
Below right side of dash
Behind glove box
Behind glove box
Main wire harness
Mode control motor
Heater sub-harness B
A,/C thermostat
Blower motor
Blower motor resistor
Recirculation control motor
Heater Sub-harness Bt '96;98 models
c743
2O-GRY
6-BRN
14-GRN
Behind front console
Behind middle of dash
Behind middle of dash
Heater sub-harness A
Heater fan switch
Heater control panel
u.
HEATER SUB.HARNESS B
l\-
203-44

) ._'
Connectol
o1
Terminal
Number ot
Cavltles/
Color
LocationConnects toNotes
Heater Sub-harness A: '99-'00 models
c440
c722
c723
c724
wlzc
c726
c727
c728
c729
c730
16.8LU
7-GRN
24-BLU
3-GRY
2-NAT
3-NAT
4.GRN
1-BRN
5-GRN
4-BRN
Under middle of dash
Behind middle of dash
Behind front console
Behind glove box
Below right side of dash
Behind glove box
Behind glove box
Behind front console
Behind glove box
Behind glove box
Main wire harness
Mode control motor
Heater sub-harness B
A'lC thermostat
Blower motor
Power transistor
Recirculation control motor
Heater sub-harness B
Air mix control motor
Blower motor high relay
Heater Sub-harness B: '99-'00 models
c723
c728
c742
c743
24.BLU
1-BRN
8-GRY
2O.BLK
Behind front console
Behind front console
Behind middle of dash
Behind middle of dash
Heater sub-harness A
Heater sub-harness A
Heater control panel conn€ctor A
Heater control oanel connector B
HEATER SUB.HARNESS A
HEATER SUB-HARNESS B
203-45