air mix HONDA CIVIC 1998 6.G User Guide

Remove the following parts Irom the dashboard'
. Driver's dashboard side cover
o Passenger's dashboard lower cover
. Dashboard center lid
Disconnect the connectors and air mix control cable'
6x1.0mm9.8 N.m 11.0 kgl.m,
D>, 1
@7 2'orftl - ---//_._J
,{nil Lll , ,"o
Ift#5 L //Hl Wlj%u|5 i//Wt qT
W72-t11 7'::--J
>: Clip locationsA>, 1 B>, 1
Loosen the bolt.
DASHBOARD
AIR MIX CONTROL
CONNECTORS
FRONT PASSENGER'SAIRBAG CONNECTOR
Remove the bolts, then lift and remove the dashboard'
CAUTION: Use proteqtive plates on the bottom ot the front pillar trim'(cont'd)
20-71
M,::;:"lx3T:iJnif:3lilH:fl"*:1::f"*'il;ili"'"
disconnect rhe front passeneer's airbas
>: Bolt, screw locaiions
A>,7B>, 1
,i( 8x125mm(!,@ 22 N.m t2.2 kstm,-v, 16 tbf.ftl
8xl.25mm I22 N.m 12.2 kgt'm, I'"tt:___J
c>, 1
@
c>,6

Dashboard
Removal (cont'd)
7. lf necessary, remove the dashboard frame from the dashboard.
>: Screw localionsa>,21 B>,4a: Nut locations, 3
>: Clip locations
l^1./'\
I Shl:' Olb'tvY/l\-]1
ra 6 x '1.0 mm
Yi.!i[11"-"'".
DASHBOARD BRACKETSIDE COVER
Installation is the reverse of the removal orocedure.
NOTE:
. Before tightening the bolts, make sure the dashboard wire harnesses are not pinched.a Make sure the connectors, antenna lead and air mix control cable are connected properly.
FRONT PASSENGER'S
OASHBOARD
20-72

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.

lllustrated Index
'96 - 98 Models
SRS components are located in this area. Review the SRS component locations, precautions, and procedures in the SRS
section {24) before performing repairs or service.
BLOWER UNITReplacement, page 21-37Overhaul, page 21-38
HEATER UNITBeplacement, page 21-39Overhaul, page 21-41BLOWERRESISTOBTest,
CONTROL MOTORTest, page 21-48Replacement, page 21'48
a/c swtTcH{wirh A/c)
MOO€MOTORTest, page 21 47Replacement, page 21'47
AIR MIX CONTROL CABLEAdjustment, page 2'1-44Replacement, page 21'43
HEATER FANswtTcHTest, page 2l'49
MODEHEATER CONTBOLPANELswrTcHEsTest, page 21 50Rgplacement, page 2'l-42Overhaul, page 21-43
TEMPERATURE CONTROLLEVERAdiustment, page 21 44
Detroster-aqtivated A/C System
Turning the defroster on activates the A,/C and sets the air flow mode to FRESH. lt is possible to turn the A,/C off or to
change the air flow to RECIRCULATE by pressing the A/C bunon or the FRESH/RECIRCULATE button.
21-2

'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

Troubleshooting -'96 - 98 Models
Symptom Chart
NOTE;
. Check the engine coolant level. and allow the engine to warm up before troubleshooting.
. Any abnormality must be corrected before continuing the test.
. Because of the precise measurements needed. use a multimeter when testing.
o Before performing any troubleshooting procedures check:- Fuses No. 41 11.5 Al, No. 55 (40 A) in the under-hood fuse/relay box. and No. 17 (7.5 A) in the under-dash fuse/relay
box- Grounds No. G401, G402- Cleanliness and tightness of all connectors
SymptomRomedy
Hot air flow is low.Blower motor runs. but one or more
speeds are inoperative.
Perform the procedures in the flowchart (see page 21-8).
Blower runs properly.Check for the following:. Clogged heater duct. Clogged heater outlet. Incorrect door position
No hot air flow.Blower motor does not run at all,Perform the procedures in the flowchart (see page 21-10).
Blower motor runs.Check for the following:. Clogged heater duct. Clogged blower outlet. Clogged heater valve. Faultv air mix door. Heater valve cable adjustment (see page 21-44). Air mix control cable adiustment (see page 2'l-441. Faulty cooling system thermostat (see section 10). Clogged evaporator (with air conditioning). Frozen evaporator {with air conditioning)
Mode control motor does not run, or one or more modes
are inooerative.
Perform the procedures in the flowchart (see page 21-13).
Recirculation control door does not chanqe between
FRESH and RECIRCULATE.
Perform the procedu.es in the flowchan (see page 21-16).
Both heater and A,/C do not work.Perform the procedures in the flowchart (see page 21-18),
21-6

Troubleshooting -'99 - 00 Models
Self-diagnosis Function
The heater control panel has a self-diagnosis function.
Running the Self-diagnosis Funqtion
Set the mode control dial to the Vent position, and turn the ignition switch ON fll). Within six seconds after turnang the igni_tion switch on. press the recirculation control switch the required number of times depending on the recirculation indicatorlight status:
.lftheindicatorlightisON,presstherecirculationcontrolswitchfivetrmes.
.lftheindicatorlightisOFF,presstherecirculationcontrol switch six rrmes.The recirculation indicator light will come on for two seconds. then blink the Diagnostic Trouble code {DTc} to indicate afaulty component. lf no DTc's are found, the indicator light will not blink after the initial two second liqht.
DTC Indication Pattern (S6e DTC 2l:
Recirculationindicato.light on
Recirculationindicatorlight off2 sec
,/1.5 soct
' 0,3 secWithin six seconds atter theignition switch is turned ON (lll,pross the recirculation controlswitch the required number ottimes depending on the rocircu-lation indicetor light status
0.3 sec
VENT POSITIONMODE CONTROL DIAL
RECIRCULATIONCONTROL SWTCH
DTC Troubleshooting Index
Diagnostic
trouble
code (DTCI
Rgcirculation
indicator lightComponent with problemPossible causeSee page
One blinkAir mix control motorObstructed door, laulty motor21-21
2Two blinksAir mix control motorOpen or short circuit21-23
ln case of multiple problems, the recirculation indicator light will indicate only one DTc with the least number of blinks.
Resetting the Self-diagnosis FunctionTurning the ignition switch OFF will cancel the self-diagnosis function, After completing repair work, run the setf diagnosisfunction again to make sure that there are no other malfunctions.
21-20
@
At
V'

Air Mix Gontrol Motor
Recirculation indicator light indicates Diagnostic Trouble code (DTC) 1l A problem in the air mix control linkage, door and
motor.
The air mix control motor regulates the mixture of cool/hot air according to outputs from the heater control panel'
Self-diagnosis circuit check indi'
cates a Problem in the air mix
conlrol motor circuit,
Check th6 aii mix conirol motor:
1. Disconnect the air mix control
motor 5P connector.
2. Test the air mix control motor(see page 21-46).
check the air mix control linkage
and doors:1. Remove the air mix control
motor (see Page 21-46)
2. Check the air mix control link-
age and doors lor smooth
movement.
ls the air mix control motor OK?
Do the air mix control linkage and
doors move smoolhlY?
R€olace the air mix control motor'
Check tor a short in the wiles:
1. Disconnect the heater controlpanel 20P connector-2. Check for continuitY between
body ground and the heater
control panel 20P connector
terminals No.3 and 4 individ'
uaIY.
Ropair any short in th€ wire{s}
betweon the heater control Paneland the air mix control motor'
HEATER CONTROL PANEL 2OP CONNECTOR
RED/WHTRED/YEL
Wire side ot female terminals
(cont'd)
fo page 21-22
21-21

Troubleshooting -'gg - 00 Models
Air Mix Control Motor (cont'dl
Frcm page21-21
AIR MIX CONTROL MOTOR5P CONNECTORWire side ot female terminals
Check fo..n open in the wires:Check for continuity between lol-lowing terminals of the heatercontrol panel 20P connector andthe air mix control motor 5P con-
20P: 5P:No3 _ No. 1No.4 - No.5
Repair any open in the wiro(s)bdtwoon tha hoator control panaland air mix control motor.
Check for loo3e wires or poorconneclions at the heater controlpanol 20P connoctor and at theair mix control motor 5P connoc-to.. It the connections .rc good,substitute a known-good hoaiercontrol panel, and rech6ck. lf thesymptom/indicrtion goes away,replac6 the original heater con-trol panel.
21-22

RecirculationindicatorIightindicatesDiagnosticTroublecode(DTc)2:AprobIemintheairmixcontro|motorcircuit.
The air mix control motor regutates the mi)dure of cool/hot air according to outputs from the heater control panel'
Self-diagnosis circuit check indi-
crl6s a problgm in tho air mix
contiol motor circuit.
Check th6 rir mix control motor:
1. Disconnect the air mix control
motor 5P connector'
2. Test the air mix control motor(see page 21-46).
Check the air mix control linkage
and doors:1. Remove the air mix control
motor (see page 21'46).
2. Check the air mix control link-
age and doors for smooth
ls the air mix control motor OK?
Do the air mix control linkage and
doors move smoothlY?
Roglace the air mix conlrol motor.
Check for r short in the wiresl
1. Disconnect the heater controlpanel 20P connector.2. Check for continuity between
body ground and the heater
control panel 20P connector
terminafs No. 3,4. 12,15 a^d
20 individually
Bep.ir any short in the wire{s)
between the h€rter control panel
and th6 air mix control motor.ls there continuity?
HEATER CONTROL PANEL 2OP CONNECTOR
BEO/WHTREO/YEL
PNK/BLK
Wire side of female terminals
(cont'd)
Io page 21-24
21-23