1998 HONDA CIVIC battery

Mode control motor does not run.
or one or more modes arc inope]a-
tive.
Check the No. 17 (7.5 A) fuse in
the under-dash fuse/relay box.
Replace the Iuse. and recheck.
Check for an open in the wire:
1. Disconnect the mode control
motor 7P connector,
2. Turn the ignition switch ON (ll)-
3. MeasLrre the voltage between
the No. 1 terminal of themode control motor 7P con
nector and body ground
Repair open in the wire between
the No. 17 luse and lhe mode
control motor.ls there battery voltage?
Check the mode control motor:
1- Turn the ignition switch OFF
2, Test the mode control motor(see page 21 47).Check lhe mode control linkage
and doors:1. Remove the mode controlmotor (see page 21 47).
2. Check the mode control linkage
and doors for smooth move
ls the mode control motor OK?
Do the mode control linkage
and doors move smoothlY?
ReDlace the mode control motor'
Check for a short to Power in the
wires:1. Iurn the,gnitjon switch ON(ll).
2, Disconnect the heater controlpanel20P connector.3. Check for voltage betweenthe No. 2, 5, 6, 7, I and 9 ter'minals of the heater controlpanel 20P connector andbody ground individuallY.Repair shorl to power in the
wire{sl between the heater con-
trol oanel and the mode controlmotor. This short also damagesthe heater control Pan6l. RePair
the short to power before replac'ing the heater control Panel
ls lhere any voltage?
MODE CONTROL MOTOR 7P CONNECTOR
t2315
BLK/YEL
Wire side of female terminals
HEATER CONIROL PANEL 2OP CONNECTOR
Wire side of female terminals
NO
(cont'd)
21-25Io page 21 26

Recirculation control door does
not chango betwe€n Fresh and
Recirculate.
Check the No. l7 (7.5 A) fuse an the
underdash fuse/relay box.
Replace the fuse, and recheck.
Check lor an oPen in the wite:
1. Disconnect the recirculation
control motor 4P connector.
2. Turn the ignition switch ON (ll)
3. Measure the voltage between
the No. 1 terminal of the recir
culation control motor 4P
connector and body ground.
Repair open in the wire between
the No. 17 luse and lhe recircula-
tion control motor.ls there battery voltage?
Check the rccirculation control
motorr'] Turn the ignition switch OFF.
2. Test the recirculation control
motor (see Page 21 48i
Check the recirculation control
linkage and door:1. Remove the recirculation con_
trol motor lsee Page 2l 48).
2. Check the recirculation control
linkage and door for smooth
movement.
Reoair the recirculation conlrol
linkag€ or door.Do the recirculation control link_
age and door move smoothlY?
CONTROL MOTOR
side of temale terminals
RECIRCULATION CONTRC,lP CONNECTOR
q-?--T--T--T-|1l2l/l1l
f BLK/YEt(v)
!
page
(cont'd)

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

From page 21 31
ls there continuity?
YES
Check the blower motor highrelay:1. Turn the ignition switch OFF,and disconnect the iumPer
2. Remove the blower motor
high relay, and test it. {seepage 21 49).
Check lor an open in the wire:1. Connect the No. 1 terminal ofthe blower motor high relay4P connector to body ground
with a jumPer wire.2. Turn the ignition switch ON (ll).
Repair open in the wire belweenthe blower motor and the blowermotor high rolay.Does the blower motor run?
Check for an op6n in the wir6:1. Turn the ignition switch OFF,and disconnect the iumPer
2. Turn the ignition switch ON (ll).
3, Measure the voltage betweenthe No. 2 terminal of theblower motor high relay 4Pconnector and body ground.
Repair open in the wire betweenthe No. 17 fuse and the blowor
motor high relay.ls there battery voltage?
Check for an open in the wire:1. Turn the ignitaon switch OFF.2. Check for continuity betweenthe No.3 terminal of theblower motor high relay 4P
connector and body ground.
Ch6ck lor an op.n in the wirebotween the blower motor highrelay and body ground. ll the wireis OK, ch6ck for poot ground atG401 end G402.
To page 21 34
BLOWER MOTOR HIGH RELAY 4P CONNECTOR
JUMPERWIRE
Wire side of female terminals
(cont'd)
21-33

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

Heater Unit
Replacement
SRS components are located in this area. Review the
SRS component locations, precautions, and procedures
in the SRS section {24} before performing repairs or ser-
L Disconnect the negative cable from the battery.
2. Frcm under the hood, open the clamp, then discon-
nect the heater valve cable from the heater valve
arm. Turn the heater valve arm to the fully opened
position as shown.
When the engine is cool. drain the engine coolant
from the radiator (see section 10).
!@ Do not remove the radiator cap when
the engine is hot; the ongine coolant is under pres'
surg and could severely scald you.
CLAMP
HEATER VALVC CABLE
4. Disconnect the heater hoses from the heater unit.
CAUTION: Engine coolant will damage p8int.
Ouickly rinse any spilled engins coolant from painted
su aces,
NOTE: Engine coolant will run out when the hoses
are disconnected; drain it into a clean drip pan.
5. Remove the mounting nut from the heater unit.
NOTE: When removing the mounting nut, take care
not to damage or bend the fuel lines, the brake
lines, etc.
I x 1 .25 mm22 N.m {2.2 kgl.m, 16lblftl
21-39

Air Mix Gontrol Motor
't.
Test -'99 - 00 Models
Disconnect the 5P connector from the air mix con-
trol motor.
Connect battery power to the No. 1 terminal of the
air mix control motor, and ground the No. 5 termi,
nal; the air mix control motor should run, and stop
at MAX HOT. lf it doesn't, reverse the connections;
the air mix control motor should run, and stop at
MAX COOL.
lf the air mix control motor does not run, remove
it, then check the air mix control linkage and
doors for smooth movement.
lf they move smoothly, replace the air mix con-
trol motor.
AIR MIX CONTROL MOTOR
Measure the resistance between the No.2 and No.3
terminals. lt should be approximately 4.8 to 7.2 kO.
Measure the resistance between the No. 2 and No. 4
terminals. lt should be approximately 3.84 to 5.76 kO
at MAX HOT and approximately 0.96 to 1.44 kO at
MAX COOL.
21-46
5P OONNECYOB
Replacement -'99 - 00 Models
1, Disconnect the 5P connector from the air mix con-
trol motor. Remove the self-tapping screws, the airmix control motor and the flange collar.
CONTROLMOTOR
Install in the reverse order of removal. After installa-
tion, make sure the air mix control motor runs
smoothly.