ac system HONDA CIVIC 1999 6.G Workshop Manual

Troubleshooting
Central Processing Unit (CPUI
Diagnostic Troublo Code IDTC) 81: CPU Disgnosis
- With the ignition switch ON{lll. ABS indicator light doesnot go oft.- With tho SCS servi@ connec-tor conn€cted lsee page 19{6},DTC 81 is indicated.
P.oblem vedfication:1. Erase the DTC.2. Test-drive the vehicle.3. Make sure that the ABS indi,cator light comes on and DTC81 is indicated.
ls DTC 81 indicated?R€pllc6 th. ABS control unh.
The system k OK rt this time.
19-74

\il
Modulator Unit
RemovaUlnstallation
CAUTION:
. Do not spill brake tluid on the car; it may damage the paint; it brako lluid does contact the paint, wash it off immedi-
ately with wator.
a Take care not to damage or delorm the brake lin€s during removal and installation.
. To prevent the brake tluid from tlowing, plug and cover the hose €nds and ioints with a shop tow6l or equivalent
mat€rial.
NOTE| Tightentheflare nutsto 15 N.m (1.5 kgnm. l1 lbf.ft).
Removal
'1. Disconnect the modulator unit 10P and Dump motor 2P connectors.
2. Disconnect the brake lines, then remove the modulator unit.
Installaiion
1. Install the modulator unit. then connect the brake lines.
2. Connect the modulator unit 10P and oumD motor 2P connectors.
3. Bleed the brake system.
4. Start the engine, and check that the ABS indicator light goes off.
Fomright-1461
PUMP MOTOR2P CONNECTOR
J
-R
/2e'
t'
TOR UNIT
tt
19-75

Seat Belts
Child Seat Anchor Plate
Attachment points are provided for a rear seat mounted
child restraint system which uses a top tether. The attach-
ment points are located on the rear shelf or rear trim
panel, just behind the rear seat-back. When using a child
seat with a top tether, install the child seat anchor plates
securely.
2Dl4Di
NOTE; Remove the plug covers from the attachment
points of the rear shelf.
3D:
NOTE: The reartrim panel has perforations at each attach-
ment point. Cut the rear trim panel along the perforations
to make a hole.
REAR TRIMPANEL
PLUG COVERS
REAR SHELF
POINTS
20-92
NOTE:
TOOTHED WASHEB
Do not remove the toothed washer from the child seat
anchor plate. Use the child seat anchor plate with the
toothed washer attached to it.
When installing a child seat on the rear seat, follow
the instructions of the manufacturer of the child seat
Additional anchor olates are available.
@r Do not us6 the child seat anchor plate for any othel
purposs; it is designed exclusively tor installation of a
child 3eat.
. Make suro the rear seat-back is locked firmly when
installing 8 child seat.

Seat Belts
Child Seat Anchor Plate Removal/lnstallation
2DllDl
Attachment points are provided for a rear-seal-mounted child restraint system that usespoints are located on the rear shelf, tust behind the rear seat-back.The child seat anchor plates are installed in the middle and on both sides of the rear shelf.covered with the child seat anchor olate cover.
a top tether. The attachment
Each child seat anchor plate is
NOTE:
' Do not remove the toothed washer from the child seat anchor plate, Use the anchor plate with the toothed washerattached to it.
. When installing a child seat on the rear seat, follow the instructions of the manufacturer of the child seat.. When installing the anchor plates, the one with the shoner spacer goes in the middle.. Make sure the rear seat-backs are locked firmly when installing a child seat.
Unit: mm (in.)
REAR SHELF
CIIILD SEAT ANCHORPLATE COVER
MIDOLE CHILDSEAT ANCHOR
CHILO SEATANCHORPLATE COVER
CHILD SEATANCHORPLATE COVER
8 x 1.25 mm22 N.m 12.2 kgl m,
PLA
8 x 1.25 mm22 N.m 12.2 kgl.m,
I x 1.25 mm22 N.m 12.2 kgl.m,16 tbt.ftt
17 {0.67)
16 tbf.ft)
15 {0.s9)
WASHER
rl)
.t
TOOTHEO
ll ff*,".rd,',i"'"o*
SIDESEAT
I x 1,25 mmN.m {2.2 kgf.m.16 tbtftl
SIDE
16 tbf ftl
ANCHOR PLATESEAT ANCHORPLATE
ATTACHMENT POINTS
torward .
20-142
TOOTHED
12lO.47l19 (0.75)

3D:
Attachment points are provided for a rear-seat mounted child restraint system that uses a top tether' The attachment
points are located on the rear trim panel.
The child seat anchor plates are rnstalled in the middle and on both sides of the rear trim panel Each child seat anchor
plale is covered with the child seat anchor plate cover'
NOTE:
. Do not remove the toothed washer from the child seat anchor plate. use the anchor plate with the toothed washer
attached to it.
. when installing a child seat on the rear seat, follow the instructions ol the manufacturer of the child seat'
. Make sure the rear seat-backs are locked firmly when installing a child seat'
gn;1 6rn (in.)
ATTACHMENT POINTS
CHILO SEATANCHOR PLATE
CHILD SEATANCHOB PLATECOVER
8 x 1.25 mm22 N..n (2.2 kgl'm.16 tbfft)
;x?',rff{-*.
20-143

Heater and Air Conditioning
Heater '.'..""" 21'1
Air Conditioning ......."'.. "' 22-1
SUPPLEMENTAL RESTRAINT SYSTEM (SRS}
The civic sRs includes a driver's airbag located in the steering wheel hub ln addition, all models (except some
models for canada) have a passenger's airbag located in the dashboard above the glove box'
Information necessary to safely service the sRS is included in this service Manual ltems marked with an asterisk (*)
on the contents page include, or are located near, sRs components. servicing, disassembling or replacing these
items will require special precautions and tools, and should therefore be done by an authorized Honda dealer'
@-";;il rendsring the SRS inoperative, which could lead to personal iniury or deaih in the svent of a sev€re
frontal collision. all SRS service work must be pertormed by an authorized Honda d€aler'
. lmploper service procedures, including incorrest removal and instsllation of the sRs, could lead to personal
iniury caused by unintentional deployment of the airbags'
o Do not bump the SRS unit. Otherwise. the system may fait in case of a collision. or the airbags may deploy
when the ignition switch is ON {ll}'
. sRs electrical wiring harncsses are id€ntified by yellow colol coding. Related components ale located in lhe
steering column, front console, dashboard, dashboald lowet panel, and in the dashboard above the glove box'
Do not use electricaltest equipment on these circuits.

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

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
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

Heater Unit
Replacement (cont'dl
6.
7.
8.
9.
Remove the dashboard (see section 20).
Remove the heater duct (see page 21-37) or evapo-
rator (see page 22-28).
Disconnect the connectors from the mode control
motor and air mix control motor ('99 - 00 models),
then remove the wire harness clips and wire har-
ness from the heater unit. Remove the clip from the
heater duct, then remove the two mounting nuts
and the heater unit.
6x1.0mm9.8 N.m 11.0 kgl.m,7.2 lbf.ftl
HEATER UNIT
lnstall in the reverse order of removal. Make note of
the following items.
Apply sealant to the grommets.
Do not interchange the inlet and outlet heater
hoses. Make sure that the clamps are secure.
Refill the cooling system with engine coolant
(see section 10).
Connect all cables, and make sure they are prop-
erly adjusted (see page 21-44 (96 - 98 models)
or page 21-45 ('99 - 00 models)).
Make sure that there is no air leakage.
21-40