ac system HONDA CIVIC 1999 6.G Workshop Manual

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

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

Frcm page 22-14
Check lor an open in the wire:1. Turn the ignition switch OFF.
2. Disconnect the A/C pressure
switch 2P connector.3. Turn th ignition switch ON lll).4. Measure the voltage between
the No. 1 terminal of the AJCpressure switch 2P conneclorand body ground.
Check the A/C pressure switch:1. Turn the ignition switch OFF.
2. Check for continuity between
the No. 1 and No. 2 terminalsof the Ay'C pressure switch.
ls there continuity?
Check for A/C system ptessure.
ls the pressure within sPeci_f cations?Repair the A/C pressure Problem
A/C PRESSURE SWITCH 2P CONNECTOR
ls there battery voltage?
wire side of {emale terminals
A/C PRESSURE SWITCH
Repair open in the wire between
the condenser fan relay tnd the
A/C oressure switch.
1o page 22-16
(cont'd)
22-15

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)

Troubleshooting
A/C System (cont'd)
From page 22-11
. _Ff,, __
I11213[
,r,il*"-T",-.r-'..owrRE I
To page 22-19 1'96 - 98 models)
A/C THERMOSTAT 3P CONNECTOR
Wire side oI female terminals
Check tor an open in the wire:1. Turn the ignition switch OFF.2. Disconnect the A/C thermostat 3P connector.3. Turn the ignition switch ON (ll).
4. Measure the voltage betweenthe No. 3 terminal of the Ay'Cthermostat 3P connector andbody ground.
Repai. open in the wire betweentho No. 17 tuso and the A/C the.-mostat.
Check loi an open in the wi.e:Measure the voltage between theNo. 1 terminal of the A,/C thermostat 3P connector and bodyground,
Ropair open in the wire betwoenthe condedlo. lan rolay and theA/C thormostat.
ls there battery voltage?
Check the A/C th6rmostat:1. Turn the ignition switch OFF.2. Reconnect the A,/C thermostat3P connector.3. Connect the No. 2 terminal toground with a iumperwire.4. Start the engine.
Do the fan run and the com-pressor clutch engage?
To page 22-20 ('99 - 00 models)
22-18

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 Torque Specifications
O Discharge hose to the compressor (6 x 1.0 mml ............... .. .... ...............' 9.8 N'm {1.0 kgf'm,7.2 lbf'ftl
@ Discharge hose to the condenser {6 x 1.0 mm1................... '... ...... . ......... 9.8 N'm 11.0 kgf'm, 7.2 lbf'ft}
O Condenser pipe to the condenser 16 x 1,0 mm)...............'. . . . ...........'..... 9.8 N'm (1.0 kgl'm, 7.2 lbt'ft)
@ Condensel pipe to the receivel/dryer (5 x 1.0 mml......... ..... . ... . '.......... 9.8 N'm (1.0 kgl'm, 7.2 lbt'ft)
O Receiver pipe A to the leceiver/dryer {6 x 1.0 mm)......... ... .......... .. . . .... 9.8 N'm 11.0 kgf'm. 7.2 lbl'ft)
@ Receiver pipe B to the receiver pipe A 13 N m (1.3 kgf'm, 9.'l lbf'ft)
O Receiver pipe C to the receiver pipe B 13 N m (1.3 kgf'm, 9.4 lbnftl
@ Receiver pipe C to the evaporator {6 x 1.0 mm) ....... 9.8 N'm (1.0 kgf'm, 7.2 lbtftl
O Suction pipe B to the evaporator (6 x 1.0 mml................ . .........'......'....... 9.8 N'm (1.0 kgf m, 7.2 lbf'ftl
e0 Suction pipe A to the suction pipe B ...'. . ...... . ... ...... 31 N'm (3.2 kgt'm, 23 lbf'ftl
O Suction hose to the suction pipe A... ............ . . '......... 31 N'm (3.2 kgl'm, 23 lbf'ft|
@ Suction hose to the compressor (6 x 1.0 mm)................... .. . ... .. ............ 9.8 N'm (1.0 kgf'm' 7.2 lbf'ft|
@@ Compressor to the compressor bracket (8 x 1.25 mm)... ..-........'.'......-.......24 N'm (2 'l kgf'm, 17 lbf ftl
@ Compressor bracket to the cytinder block (10 x 1.25 mml 44 N'm l'1.5 kgf'm, 33 lbf ftl
@ Compressor bracket to the left front engine mounl {12 x 1.25 mm}..... . . . . .. ................. ... ... 59 N'm (6.0 kgf'm, '|i} lbf ftl
22-23

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

A/C System Service
Pressure Test Chart
NOTE: Performance Test is on page 22-24,
Test resultsRelated symptomsProbabl€ causeRemedy
Discharge (high)
pressure aDnor-
mally high
After stopping compressor. pres-
sure drops to about 200 kPa
{2.0 kgflcm,,28 psi) quickly, and
then falls gradually.
Air in systemRecover, evacuate, and
recharge with specified amount.
Evacuation: see page 22-45
Charging: see page 22-46
Reduced or no air flow through
condenser
. Clogged condenser fins. Condenser fan not work-
ing properly
Clean.
Check voltage and fan rpm.
Check fan direction.
Line to condenser is excessively
hot.
Restricted flow of refriger-
ant in system
Restricted lines
Discharge pres-
sure abnormally
High and low pressures are bal-
anced soon after stopping compres-
sor, Low side is higher than normal.
. Faulty compressor dis-
charge valve. Faulty compressor seal
Replace the compressor.
Outlet of expansion valve is not
frosted, low pressure gauge indi-
cales vacuum.
. Faulty expansion valve. Moisture in system
. Replace,. Recover, evacuate, and
recharge with specified
amount.
Suction (low)
pressure abnor-
mally low
Expansion valve is not frosted, and
low oressure line is not cold. Low
pressure gauge indicates vacuum.
. Frozen expansion valve. Faulty expansion valve
ReDlace the exoansion valve.
Discharge temperature is low. and
the air flow from vents is restricted.
Frozen evaporatorRun the fan with compressor
off. then check A,/C thermostat.
Exoansion valve is frosted.Clogged expansion valveClean or replace.
Receiver/dryer outlet is cool, and
inlet is warm (should be warm
during operation).
Clogged receiver/dryerReplace.
Suction pres-
sure abnormally
hig h
Low pressure hose and check
joint are cooler than the tempera-
ture around evaporator.
. Expansion valve open too
long. Loose expansion capillary
tube
Repair or replace.
Suction oressure is lowered when
condenser is cooled bv water.
Excessive refrigerant in sys-
tem
Recover. evacuate, and
recharge with specified amount.
High and low pressure are equal-
ized as soon as the compressor is
stopped, and both gauges fluctu-
ate while running.
Faulty gasket
Faulty high pressure valve
Foreign particle stuck in
high pressure valve
Replace the compressor.
Suction and dis-
charge pres-
sures abnormally
h igh
Reduced air flow through con-
denser.
. Clogged condenser fins. Condenser fan not work-
ing properly
Clean condenser.
Check voltage and fan rpm.
Check fan direction.
Suction and dis-
charge pressure
abnormally low
Low pressure hose and metal end
areas are cooler than evaporator.
Clogged or kinked low pres-
sure hose parts
Repair or replace.
Temperature around expansion
valve is too low compared with
that around receiver/dryer.
Clogged high pressure lineRepair or replace.
Refrigerant leaksCompressor clutch is diny,Compressor shaft seal leakingReplace the compressor.
Compressor bolt{s) are diny.Leaking around bolt(s)Tighten bolt(s) or replace com-
pressor.
Compressor gasket is wet with oil.Gasket leakingReplace the compressor.
22-26