1999 HONDA CIVIC air conditioning

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.

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

Blower Unit
Replacement
NOTE: The blower motor, recirculation control motor
and blower resistor can bs replacsd without rsmoving
th€ blower unit (see neld Page).
1. Move the temperature control to "HOT."
'96-98: Slide the temperature control lever.'99-00: Turn the ignition switch ON (ll), then turn
the temperature contol knob. Turn the ignition
switch off,
Remove the glovs box (ses ssction 20),
R€move ths s6lf-tapping screw and ths passsng6r's
dashboard low€r cover. Removo the bolt, the nut
and the kn€e bolst€r, then remove the fiv€ bolts and
the glove box trame,
Without Air Condhioning
4-a. Remove the wiro harness from the h68t€r duct, then
remove the two self-tapping scrsws and the heatsr
duct.
KNEE
GLOVE BOX FRAME
HEATER DUCT
21-37
Wrth Air Conditioning
4-b. Removo th6 ev8porator (sss pago 22-28).
6x1.0m|n9.8 N'm
6x1.0mm9.8 N'm lt'o tgf'm, t.2 lb{'ttl
Disconnoct the connectors trom th€ blower motor,
blowor r6sistor {'96 - 98 models), power transiator
('99 - 0O modsls), blowor motor high telay ('99 - 00
models) and recirculation control motor.
R€mov€ ths wiro harnoss clip from tho recirculation
control motor, and release the wir6 harnsss from ths
clamo on the blowor unit. Remove the two mount-
ing bolts, tho mounting nut and ths blowor unit'
9.8 .m 11.0 tgfm,1.2 tblfrl
lnstall in ths reverso order of removal. Mako surs
that thsre is no air leaka96.
6x1.0mm9,t N'm 11.0lgi.m,7.2 tbf.fil

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

Description
Outline
The air conditioner system removes heat from the passenger compartment by circulating refrigerant through the system
as shown below.
BLOWER FAN
EVAPORATOR(Absorption of heati
EOUALIZING TUBE(Meters pressure andimproves the expansionvalve reaction time)
into the evaporator)CAPILLATY TUBE SENSING BULB
lControls the temPerature of the
ref rigerant leaving the evaporator
by metering the expansion valve)
/\
THERMOSTAT
A/C PRESSURE SWITCH
When the refrigerant is below
200 kPa (2.0 kgtcm',28 Psi)or above 3,200 kPa 132 kgflcm',
455 psi), the Ay'C pressure
switch opens the circuit to
the A,/C switch and stops the
EXPANSION VALVE(Meters the requiredamount of refrigerant
airconditioning to Protect the
compressor.
RECEIVER/DRYER(Traps debris, andremoves morsturel
THERMAL PROTECTOR
{Opens the comPressorclutch circuit when the
compressor temPeraturebecomes too high)
RELIEF VALVE(Relieves pressure at the
compressor when thepressure is too high)
(Radiation of heat)
I
f-r--; I
(Suction and comPression,
HIGH PRESSURE VAPOR
HtGH PRESSUBE LIOUID
LOW PRESSURE LIOUID
This car uses HFC-134a (R-134a) refrigerant which does not contain chlorofluorocarbons Pay attention to the following
service items:
. Do not mix refrigerants CFC-12 (R-12) and HFC-134a (R-134a)' They are not compatible'
. Useonlythe recommended polyalkyieneglycol (PAG) refrigerant oil designedforthe R-134a compressor (SANDEN: SP-
10; DENSO: ND_OIL8). Intermixing ihe re-commended (pAG) refrigerant oil with any other refrigerant oil will result in
compressor failure.
. All A,,ic system parts {compressor, discharge line, suction line, evaporator, condenser, receiver/dryer, expansion valve'
O-rings for joints) have to be proper for refrigerant R- 134a Do not confuse with R-l2 parts'
. Use a halogen gas leak detector designed for refrigerant R-134a
. R-12 and R-134a refrigerant servacing equipment are not interchangeable. Use only a recovery/recycling/charging station
that is u,L.-listed and is certified to meet the requirements of sAE J2210 to service R-134a air conditioning systems'
. Always recover the refrigerant R-134a with an approved recovery/recycling/charging station before disconnecting any
A,/C fitting.
S]
22-5

A/C Service Tips and Precautions
The air conditioner system uses HFC-134a (R-134a) refrigerant and polyalkyleneglycol (PAG) refrigerant oil*, which are not
compatible with CFC-12 (R-12) refrigerant and mineral oil. Do not use R-12 refrigerant or mineral oil in this system, and do
not attempt to use R-12 servicing equipmenU damage to the air conditioner system or your servicing equipment will result.*Sanden SP-10:
. P/N 38897 - P13 - A0lAH: 120 ml 14ll.oz, 4.2lmp.oz)
. P/N 38899 - P13 - A0l | 40 mf 11 1/3ll.oz,1.4 lmp'oz)
Use only service equipment that is U.L. listed and is certified to meet the requirements of SAE J2210 to remove R 134a
from the air conditioner system.
CAUTION: Exposure to air conditioner ref;ige;ant and lubricant vapol or mist can irritate syes, nose and throat, Avoid
breathing the air conditioner refrigerant and lubricant vapor or misl.
lf accidental system discharge occurs, ventilate work area before resuming service.
R-'134a service equipment or vehicle air conditioner systems should not be pressure tested or leak tested with compressed
ai.
!@@ some mixtures of air and R-t3ila have been shown to be combustible at elevated pressures and can result
in tire or explosion causing iniury or property damage. Never use compressed air lo pressure tesl R-134a service equip-
ment or vehicle 8ir conditioner systoms.
Additional health and safety information may be obtained from the refrigerant and Iubricant manufacturers.
L Always disconnect the negative cable from the battery whenever replacing air conditioning pans.
2. Keep moisture and dust out of the system. When disconnecting any lines, plug or cap the fittings immediately; don't
remove the caps or plugs until just before you reconnect each line.
3. Before connecting any hose or line, apply a few drops of refrigerant oilto the O-ring.
4, When tightening o. loosening a fitting, use a second wrench to support the matching fitting.
5. When discharging the system, use a R-134a refrigerant recovery/recycling/charging station; don't release refrigerant
into the atmosphere,
6. Add refrigerant oil after replacing the following parts:
NOTE:
. To avoid contamination, do not return the oil to the container once dispensed, and never mix it with other refriger-
ant oils.
. lmmediately after using the oil, replace the cap on the container, and seal it to avoid moisture absorption.
. Do not spill the refrigerant oil on the vehicle; it may damage the paint; if the refrigerant oil contacts the paint, wash
it off immediately.
Condenser .......2o ml (2/3 fl.oz, 0.7 lmp.ozl
Evaporator .,.,.,. i[5 m{ 11 213 tl.oz,1,6lmp.ozl
Line or hose ..... 10 mf (1/3 fl.oz, 0.4 lmp.ozl
Receiver/Dryer 10 m{ (1/3 fl.oz,0.'l lmp.ozl
Leakage repair 25 m{ (5/6 fl.oz, 0.9 lmp.ozl
Comptessor ... For compressor replacement. subtract the volume of oil drained trom the
removed compressor from A, and drain the calculated volume of oilfrom the new
compressor: A - Volume of removed compressor: Volume to drain from new
comoressor.
A: SANDEN 130 mf l/t 113 ll.oz, 4.6 lmp'ozl; DENSO 140 mf {4 213 ll'oz, 1.9
lmp.oz),
NOTE: Even if no oil is drained from the removed compressor, don't drain more
than S0 m{ 112Ell.oz,1.8 lmp.oz) fromthe new compressor.
REMOVED NEW
COMPRESSORCOMPRESSOR
*DENSO ND-OlL 8l
. P/N 38897 - PR7 - A01AH: 120 ml (4 fl.oz)
. P/N 38899 PR7-A01:40mf (1 1/3fl'oz)
rereW W0000
22-22
-0_!- -0_a
Tol l00l
| | lffi 1 onrrrutrc I
fi+-sAME
LEvEr...+jEf,voLUME
J
^

A/C System Service
Performance Test
The performance test will help determine if the air con-
ditioner system is operating within specifications.
Use only service equipment that is U.L.-listed and is cer-
tified to meet the reouirements of SAE J2210 to remove
HFC-134a (R-134a) from the air conditioner system.
CAUTION: Exposure to air conditionor rofrigerant and
lubricant vapor or mist can irrilalo €yes, nose and
throat. Avoid breathing tho air conditioner rstrigerrnt
and lubricant vapor or mist,
lf accidental system discharge occurs, ventilate work
area before resuming service.
R-134a service equipment or vehicle air conditioner sys-
tems should not be pressure tested or leak tested with
compressed air.
@ some mixtur$ of air and R-134a have been
shown lo b9 combustible rt glgvatad pr€ssur63 and can
resull in tire 01 oxplosion causing inlury ot property
damage. Never uao compre33ed air to pressure t99t R-
134a ssrvico 6quipmsnt or vohicla air conditioner sys-
tems.
Additional health and safety information may be obtained
from the refrigerant and lubricant manufacturers.
'1. Connect a R-134a refrigerant recover/recycling/
charging station to the vehicle, as shown, following
the equipment manufacturer's instructions.
2. lnsert a thermometer in the center vent outlet.
Determine the relative humidity and air tempera-
ture,
Test conditions:
. Avoid direct sunlight.
. Open hood.
. Open front doors.
. Set the temDerature control lever or dial to MAX,
COOL, the mode control switch or dial on VENT
and the recirculation control switch on RECIRCU-
LATE.
. Turn the A,/C switch on. and the heater fan switch
on MAX.
. Run the engine at 1,500 rpm.
. No driver or passengers in vehicle
After running the air conditioning for 10 minutes
under the above test conditions, read the delivery
temperature from the thermometer in the dash vent
and the high and low system pressure from the A,/C
gauges.
Recovery/Rocycling/Charging Station
22-24

Compressor (DENSO)
Replacement
1.lf the compressor is marginally operable, run the
engine at idle speed, and let the air conditioning work
for a few minutes, then shut the engine off
Disconnect the negative cable from the battery'
Recover the refrigerant with a recovery/recycling/
charging station lsee page 22-271
Remove the each bolt, then disconnect the suction
and discharge lines from the compressor' Plug or
cap the lines immediately after disconnecting them
to avoid moisture and dust contaminatlon.
6 x '1.0 mm9.8 N.m (1.0 kgf m,7.2 lbfft)
Remove the condenser, but do not disconnect the dis-
charge hose from the condenser (see page 22-441'
Remove the power steering pump belt (see sectron
17]-.
7. Loosen the pivot bolt of the idler pulley bracket and
the adjusting bolt. then remove the A,/C compressor
belt from the pulleys. lf necessary, remove the mount-
ing bolts from the left front mount. then remove the
fuC compressor belt through the gap between the
bodv and the left front mount.
'10 x 1,25 mm4,0 N.m (,1.5 kgf'm. 33 lbt ftl
Disconnect the compressor clutch connector, then
remove the mounting bolts and the compressor'
PIVOT BOLT10 x 1.25 mm4,1 N.m (4.5 kgt'm,33 lbfft)
COMPRESSOR
24 N.m (2.4 kgf m, 17 lbf ftl
(cont'd)
22-37