2000 HONDA CIVIC Relay fan

Heater
lllustrated Index
'96 - 98 Models ................................ 21'2
'99 - 00 Models ................................ 21'3
Circuit Diagram
'96 - 98 Models .....21-4
'99 - 00 Models ................................ 21-5
Troubleshooting - '96 - 98 Models
Symptom Chart ............................... 21-6
Heater Control Panel Input/
Output Signals ..............,.............. 21-7
Flowcharts
Blower Motor Speed ................... 21-8
Bf ower Motor ,...21'10
Mode Control Motor ............... ,.'.' 21-13
Recirculation control Motor ....... 21-16
Heater Control Panel ................ ... 21 -14
Troubleshooting - '99 - 00 Models
Symptom Chart ............................... 21-19
Seff-diagnosis Function ............,,,.... 21-20
Flowcharts
Air Mix Control Motor ......,.......... 21-21
Mode Control Motor ............... ..... 21 -25
Recirculation Control Motor ....... 21-27
Bf ower Motor Speed .............. .....21'29
Bf ower Motor ....21-31
Heater Control Panel ................,.. 21-35
Heater Control Panel Input/
Output Signals ............................. 21-36
Blower Unit
Repf acement .........21-37
Overhaul ................ 21-38
* Heater Unit
Replacement ....'....21-39
overhaul """" """' 21-4'l
Heater Control Panel
Repfacement .........21'42
Overhaul -'96 - 98 Models ........... 21-43
Temperature Control
Adjustment - '96 - 98 Models """" 21-44
Adiustment - '99 - 00 Models .......21-45
Air Mix Control Motor
Test - '99 - 00 Models ...........' .......21'46
Replacement - '99 - 00 Models ....21'46
Mode Control Motol
Test ................, .,...'.21'47
Replacement '.'."...21-47
Recirculation Control Motor
Test ................. .......21-48
Repf acement ......." 21-48
Relays
Test ................. .......2'l-49
Heater Fan Switch
Test - '96 - 98 Models ............. .......21-49
Mode Control Switch
Test -'96 - 98 Models ..........."....... 21-50
Power Transistor
Test - '99 - 00 Models ....'........ ....".21-50
*: Read SRS Drecautions before working in this area.

'99 - 00 Models
SRS components are located in this area, Review the SRS component locations, precautions, and procedures in the SRS
section (24) betore perfoming repairs or service.
HEATER UNITReplacement, page 21'39
Overhaul, page 21-41
BLOWEB UNITReplacement, page 21-37Overhaul, page 21 38
HEATER FANswtTcH
RECIRCULATIONCONTROL MOTORTest, page 21-48Beplacement, page 21-48
AIR MIX CONTROL MOTOBTest, page 21-46Replacement, page 21 46
BLOWERTest, page 21-49
POWER TRANSISTORTest, page 21 50
HIGH RELAY
MODE CONTROLDIALHEATER VALVE CABLEAdjustment, page 21 45TEMPERATURE CONTROLDIALAdjustment, page 21-45
REAR WINDOWDEFOGGERswtrcHSee section 23MODEMOTORTest, page 21 47Replacement, page 2 l-47A/C SWTTCH
lwith A/cl
CONTROL SWITCH
21-3

RelaysHeater Fan Switch
Test
There should be continuity between the No 1 and No. 3
terminals when power and ground are connected to the
No.2 and No. 4 terminals, and there should be no conta-
nuity when power is disconnected.
Blower motor relaY
. Blower motor high relay ('99 00 models)
,I It;€'Y )
Test -'96 - 98 Models
Check for continuity between the terminals according to
the table below.
lerminal
Position14253
OFF
1IrJ
2o-o
3o-a
4c)-{
21-49

Air Conditioning
Speciaf Tools ......'.....' 22-2
f f f ustrated f ndex ......................... ".......' 22-3
Wiring/Connector Locations'.........'.... 22'4
Description
Outfine ............ .......22-s
Circuit Diagram
'96 - 98 Models ......"..........".......'.... 22-6
'99 Modef """""""' 22-7
Troubleshooting
Symptom Chart ".'......""................. 22-8
Flowcharts
Condenser Fan .........".................,..'. 22-9
Compressor .....""" 22-12
A/C System .........'.22'17
A/C Thermostat
Test ........'.......' """'22'21
Relays
Test ....."'......... ..""'22-21
A/C Service Tips and Precautions ......22-22
A/C System Torque Specifications '...22-23
A/C System Service
Performance Test ... '."......... ".... ....'..22-24
Pressure Test Chart .................. .... "' 22-26
Recovery ...".........," 22-27
Evaporator
Replacement .....",' 22'24
Overhauf .....-.....""' 22'29
Compressor {SANDEN}
Repf acement ......'.' 22-30
fffustrated fndex ......"..................'.... 22'32
Cf utch Inspection ......... "............ ...... 22-33
Clutch Overhau I ........................ ....... 22-34
Thermal Protector Replacement .... 22-36
Relief Valve Replacement ......'..."". 22-36
Compressor (DENSO)
Repfacement ..""',' 22-37
lf lustrated Index ............................... 22-39
Clutch lnspection ............."'...... "'.... 22-40
Cf utch Overhaul .....................'......... 22-41
Ref ief Valve Replacement'..'......"'.. 22-42
A/C Compressor Belt
Adiustment ............22'43
Condenser
Repfacement .......,,22'44
A/C System Service
Evacuation ...,,,.......22-45
Charging '..........--'..22'46
Leak rest """""""'22-46

Wiring/Gonnector Locations
A/C DIODE.CONDENSER FAN RELAY,COMPRESSOR CLUTCH RELAY(Located in the under,hood fuse/relay box)
COND€NSER FANCONNECTOR
COMPARTMENTWIRE HARNESS
CONNECTOR
22-4

Circuit Diagram
UNDER DASHFUSE/RELAY 8OX
N0.17 (7.54)
'96 - 98 Models
UNDER.HOOD FUSEi BELAY BOX
WHT/SLU BLKYEL
BLK
+
G751
3
'o
I8LK
I
G40lG402
GNITON SWITCH
N0.41 (8rA) N0.42 (40A)
COMPBESSORCLUTCHBELAY
BLUMHT
,l
(E) i,T'
BLUi BED
A/c ITHERMOSTAI BLU/REO
CONDENSEFFAN MOTOR
*F,.X,
FAN rl
BLK
{
G401G402
HEATERswrlcH
32
22-6

Troubleshooting
Symptom Chart
NOTE:
. Any abnormality must be corrected before continuing the test.. Because of the precise measurements needed. use a multimeter when testinq.. Before performing any troubleshooting procedures check:- Fuses No. 47 l7 -5 Al, No. 56 (20 A) in the under-hood fuse/relay box, and No. 17 (7.5 A) in the under_dash fuse/relavbox- Grounds No. c401, c402, G751- Cleanliness and tightness of alt connectors
SymptomRemedy
Condenser fan does not run at all.Perform the procedures in the flowchart {see page 22-9).
Compressor clutch does not engage.Perform the procedures in the flowchart lsee page 22-12).
Ay'C system does not come on (compressor and fan),Perform the procedures in the flowchan (see page 22-17).
Both heater and A,/C do not work.. '96 - 98 models-Perform the procedures in the flowchart
{see page 21-18).. '99 - 00 models-Perform the procedures in the flowchart(see page 21-35).
22-8

Condenser Fan
CONDENSER FAN RELAY 4P SOCKET
JUMPERwlRE
(cont'd)
22-9
Conden3er fan does not run at all.
Check the No. 56 (20 A) fuse in the
unde.hood frJse/relaY box, and the
No. 17 (7.5 A) fuse in the under-
dash fuse/relay box.
Reolace the fuse{s), and techeck
Remove the condenser lan rclaY'
and test it (see page 22 21i
Replace the condensei fan relav.
Check the under-hood tus6/relaY
Measure the vohage between the
No. 2 terminalofthe condenser fan
relav 4P socket and bodv ground.
ls there battery voltage?
Check the condenser lan Powersupply circuit:Connect the No. 1 and No. 2 teF
minals of the condenser fan relay
4P socket with a jumper wire
Does the condenser fan run?To page 22-10
Io page 22 11