1996 HONDA CIVIC under-hood

Troubleshooting -'99 - 00 Models
Symptom
Mode control motor does not run, or one or more modes are inoperat've'
Recirculation control door does not change between Fresh and Recirculate'
Blower motor only runs on high speed position; it does not run in any other speed positions
Blower motor does not run at all.
Both heater and Ay'C do not work
See pags
a1_tq
21-21
21-29
21-31
21 35
Symptom Chart
For electrical malfunctions which are indicated by the self-diagnostic system, refer to self-diagnosis function (see next
page).
Note these items before troubleshooting a symptom'
. Check the engine coolant level, and allow the engine to warm up before troubleshooting'
. Any abnormality must be corrected before continuing the test
.Becauseoftheprec|semeasurementsneeded,UseadigitaImu|timeterwithanoutputoflmAor|essatthe20ko
range when testing
. Before performing any troubleshooting procedures check:
- Fuses No. 41 115 Al, No 55 (40 A)]n the under-hood fuse/relay box' and No 17 (7 5 A) in the under-dash fuse/relav
box- Grounds No. G401, G402
- Cleanliness and tightness of all connectors
21-19

Blower Motor
BLOWER MOTOR 2P CONNECTOR
Wire side of lemale terminals
JUMPERWIRE
(cont'd)
21-31
Blower motor does not run at all.
Check the No. 55 (40 A) Iuse in
the under-hood fuse/relay box,
and the No. 17 (7.5 A){use in the
undeFdash fuse/relay box.
Boplace th€ fuse(3), and rechock.
Check th€ blow€r motor Powelsupply circuit:1. Disconnect the blower motor
2P connector.2. Turn the ignition switch ON {ll).
3, Measure the voltage between
the No. 1 terminal oI the blow
er motor 2P connector and
body ground.
ls there battery voltage?
Check tha blower motor:
1. Turn the ignition switch OFF
2. Reconnect the blower motor
2P connector.3. Connect the No.2 terminal o{
the blower motor 2P connector to bodv ground with a
tumper wire.4. Turn the ignition switch ON {ll}
Does the blower motor run?
fo page 21-32
To page 21-33

Troubleshooting -'99 - 00 Models
From page 21-31
Check the blower motor relay:1. Turn the ignition switch OFF.2. Remove the blower motorrelay from the under hoodfuse/relay box, and test it- (seepage 21'49).
Replace the blower motor relay.
Check the under-hood tuse/relaybox:Measure the voltage between theNo. 3 terminal of the blowermotor relay 4P socket and bodyground.
Check tor an open in the wire:1. Turn the ignition switch ON (ll).
2. Measure the voltage betweenthe No. 4 terminal of theblower motor relay 4P socketand body ground.
Repair opon in lhe wire betweenthe No. 17 fuse and the blowetls there battery voltage?
Check for an open in the wire:1. Turn the ignition switch OFF.2. Check for continuity betweenthe No. 2 terminal of theblower motor relay 4P socketand body ground.
Check lor an ooen in the wirebetween the blowor motor relayand body ground. It the wiie isOK, check for poor ground atG401 and G402.
ls there continuityl
Repair open in the BLU/WHTwiae between the blower motorrelay and the blower motor,
BLOWER MOTOR RELAY 4P SOCKET
21-32

Both heater and A/C do nol work.
checkthe No.47 (7.5 A)fuse in the
under-hood fuse/relay box, and theNo. 17 {7.5 A) fuse in the under-
dash fuse/relay box.
ReDlace the tuse{s), and recheck.
Check lor an open in the wire:
1. Disconnect the heater controlpanel 8P connector,2. Turn the ignition switch ON (ll).
3. Measure the voltage between
the No. I terminal of the
heater control panel 8P con-
nector and body ground.
Repair open in the wire betweenthe No. '17 luse and th6 heatercontrol oanel,ls there battery voltage?
Check for an open in the wire:
1. Turn the ignition switch OFF.
2. Disconnect the heater controlpanel20P connector.3. Measure the voltage lletweenthe No. 10 terminal of theheater control Panel 20P con-nector and body ground.
Repair op6n in the wir€ between
the No. il7 tuse and the heater
controloanel,ls there battery voltage?
Check for an open in the wite:Check for continuity between theNo. 6 terminal of the heater con
trol panel 8P connector and bodyground.
Ch6ck tor an open in lhe wire
betwoen the heator control Paneland bodv ground. lf the wire isOK, check for poor ground atG401 and G402.
ls there continuity?
Check for looso wires or Poolconneciions at the heater controloanel 8P and 20P connectors. lf
the connections are good, substi'
tute a known-good heat€r con-trol Danel, and recheck. lI thesymptom/indication goes awaY,r6place the original h€ater con-troloanel.
HEATER CONTROL PANEL 8P CONNECTOR
BLK/YEL
Wire side of female terminals
HEATER CONTROL PANEL 2OP CONNECTOR
Wire side of temale terminals
I2
1578
BLK
o
1
4I
v

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

A/C System
CONDENSER FAN RELAY 4P SOCKET
A/C system does not come on
{comDressor and fan).
Check the No. 56 fuse in theunder'hood fuse/relay box andthe No. 17 fuse in the under-dashfuse/relay box.
ReDlace the fus6{s}, and recheck.
Check for tn open in the wire:
1. Remove the condenser lanrelay from the u nderhood
luse/relay box.2. Turn the ignition switch ON {lli.3- Measure the voltage betweenthe No. 4 terminal of the condenser fan relav 4P socketand body ground.
Repair open in the wire between
the No. 17 fuse and the con-denser fan r6lay,
Check the under-hood fus€/r6laybox:Measure the voltage between the
No. 2 terminal of the condenser
fan relay 4P socket and bodyground,
YES
Io page 22-18
(cont'd)

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