1998 HONDA CIVIC valve stem

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

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 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

Compressor (SANDENI
Thermal Protestor Replacement
1. Remove the bolt, the ground terminal and the hold-er. Disconnect the field coil connector. then removethe thermal Drotector.
7.{ N.m 10.75 ksf.m,5lbtfr)
/
SILICONE SEALANT
3. Install in the reverse order of removal.
GROUNDIERMINAL
HOI.I'ER
PNOTECTOR
Replace the thermal protector with a new one. andapply silicone sealant to the top of the thermal pro-
tector.
22-36
oo
Relief Valve Replacement
'1.Remove the relief valve and the O-ring.
NOTE:
. Do not let the compressor oil runout.. Make sure that no foreign matter enters the sys-tem,
RELIEFVALVE9.8 N.m {1.0 kgl.m,7.2 tbl.lrl
O.RINGReplace.
Clean the mating surfaces.
Replace the O-ring with a new one at the relief valve.and apply a thin coat of refrigerant oil beforeinstalling it.
NOTE:
. To avoid contamination. do not return the oil tothe container once dispensed, and never mix it
with other refrigerant oils.o lmmediately after using the oil, replace the capon the container, and seal it to avoid moistureabsorption.
. Do not spill the refrigerant oil on the vehicle; itmay damage the paint; if the refrigerant oil con-tacts the paint, wash it off immediately.
Install and tighten the relief valve.
Charge the system {see page 22-461, and test itsperformance 1se6 page 22-241.

Compressor (DENSOI
Replacement (cont'd)
9. Remove the bolts, the suction service valve and theO-ring from the compressor,
lf necessary, remove the compressor bracket as fol-lows.
. Remove the nut and the washer from the left frontmount. When tightening the nut to the left frontmount, make sure the washer is set p.operly onthe left front mount as shown.
a Remove the mounting bolts and the compressor
bracket.
12 x 1,25 rnm59 N.m 16.0 kgfrm,
10.
LEFT FRONTMOUNT€ rbf.fi)Roplace.
WASHEB
x 1.25 mm
2s.5 N.m {2.6 kgf.m. 18.8 tbtttl
4/r N.m {4.5 kgf.m, 33 lbt ft}
22-3A
1 1. Install in the reverse order of removal, and note thesertems:
lf you're installing a new compressor. drain all therefrigerant oil from the removed compressor. andmeasure its volume. Subtract the volume ofdrained oil from '140 ml (4 28 fl{,z, 4.9 lmpoz); theresult is the amount of oil you should drain fromthe new compressor (through the suction fifting).Replace the O-rings with new ones at each fining,and apply a thin coat of refrigerant oil beforeinstalling them. Be sure to use the right O,ringsfor HFC-134a (R-134a) to avoid leakage.
Use refrigerant oil {DENSO, ND-OtL8) for HFC-134aDENSO piston type compressors only.To avoid contamination, do not return the oil tothe container once dispensed, and never mix itwith other refrigerant oils.
lmmediately after using the oil, replace the capon the container, and seal it to avoid moisture
absorption.
Do not spill the refrigerant oil on the vehicle; itmay damage the paint; if the refrigerant oil con-tacts the paint, wash it off immediatelv.
Adjust the ly'C compressor belt (see page 22-43)and the power steering pump belt (see section 17).Charge the system (see page 22-46), and test itsperformance (see page 22-24!..

Compressor (DENSO)
Clutch Overhaul (cont'd)
Remove the screw from the field coil ground termi-nal. Remove the snap ring A with snap ring pliers.
then remove the field coil. Be careful not to damaoethe field coil and compressor.
SNAP NING AReplace.
Reassemble the compressor clutch in the reverseorder of disassembly, and note these rrems:
o Install the field coil with the wire side facingdown.
a Clean the pulley and compressor sliding surfaceswith non-petroleum solvent.. Install new snap rings, and make sure thev arefully seated in the groove.
. Make sure that the pulley turns smoothly afterit's reassembled.
. Route and clamp the wires p.operly or they canbe damaged by pulley.
FIELOcorL
22-42
13.2 N.m 11.35 kgt m,9.76lbtttl
Relief Valve Replacement
L
4.
Recover the refrigerant with a recovery/recycling/charging station {see page 22-27),
Remove the relief valve and the O-ring. plug theopening to keep foreign matter from entering thesystem and the compressor oilfrom running out.
Clean the mating surfaces.
Replace the O-ring with a new one at the relief valve.and apply a thin coat of refrigerant oil before install-ing it.
Remove the plug, and install and tighten the reliefvatve.
Charge the system (see page 22-46), and test its per-formance (see page 22-24),

A/C System Service
Charging
Use only service equipment that is U.L.-listed and is cer-
tified to meet the requirements of SAE J2210 to remove
HFC-134a (R-134a) from the air conditioner system.
CAUTION: Exposure to air conditioner refrigerant and
lubricant vapor or mist can irritale eyes, nose and
throat. Avoid breathing the air conditioner retrigerant
and lubricant vaoor or mist,
lf accidental system discharge occurs, ventilate workarea before resuming service, Additional health and
safety information may be obtained from the refrigerant
and lubricant manufacturers.
Refrigerant capacityt 600 - 650 g 121.1 - 22.9 ozl
CAUnON: Do not overcharg€ the system; the comprcssor
will be damaged.
Connect a R-134a refrigerant recovery/recycling/charging
station to the vehicle, as shown, following the equipment
manufacturer's instructions.
Recovery/Recycling/Charging Station
22-46
Leak Test
Use only service equipment that is U.L,-listed and is cer-
tified to meet the requirements of SAE J2210 to remove
HFC-134a (R-134a) from the air conditioner system.
CAUTION: Exposure io air conditioner refrigerant and
lubricant vapot or mist can itritats eyes, no36 and thtoat.
Avoid breathing the air conditioner refrigeranl and lubri-
cant vapor or mist,
lf accidental system discharge occurs, ventilate workarea betore resuming service.
R-134a service equipment or vehicle air conditioner sys-
tems should not be pressure tested or leak tested with
comoressed air.
@ some mixtures of air and R-134a have
been shown to be combugtibls at elevatgd prossures
and can result in tire or explosion causing iniuly orplopgrty damage. Nev€r usc compre33od air to pressure
test R-13'la servica oquipment or yohiclo air conditionor
systems.
Additional health and safety information may be obtained
from the refrigerant and lubricant manufacturers.
1. Connect a R-134a refrigerant recove rylrecycling/
charging station to the vehicle, as shown in the pre-
vious column, following the equipment manufactur-
er's instructions.
NOTE; Be sure to install the same amount of new
refrigerant oil back into the A,/C system before charg-In9.
Open the high-pressure valve to charge the system
to the specified capacity, then close the supply
valve, and remove the charging system couplers.
Rofrigerant capacity: 600 - 650 g (21.1 - 22.9 oz)
Check the system for leaks using a R-134a refriger-
ant leak detector with an accuracy of 14 9 10.5 ozlper yea. or better.
lf you find leaks that require the system to be opened(to repair or replace hoses. fittings. etc.), recover the
system according to the Recovery Procedure on page
22-27.
After checking and repairing leaks. the system must
be evacuated (see System Evacuation on page 22-451.