1996 HONDA CIVIC 1 page

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

Troubleshooting
Gompressor (cont'dl
'96 -98 models:
ECM/PCM CONNECTOR C 13lPI
Wire side ot female terminals
'9!t - 00 mod.bi
ECM/PCM CONNECTOR A I32P)
Wire side ot female terminals
*How to use the backprobe setsConnect the backprobe adapters to the stacking patch cords, andconnect the cords to a multimeter. Using the wire insulation as aguide for the contoured tip of the backprobe adapter, gently slidethe tip into the connector from the wire side until it comes in con-tact with the terminal end ofthe wire {see section 11}.
From page 22-15
Check for an open in thg wire:'1. Reconnect the A"/C pressure
switch 2P connector.2. Make sure the A/C switch isOFF, then turn the ignitionswitch ON (ll).
3. Using a *Backprobe Set {T/N07SAZ - 001000A), measurethe voltage between the No. 5terminal of the ECM/PCM con-nector C (31P) and bodyground with the EcM/PcMconnectors connected ('96 -
98 models), or between theNo. 27 terminal of theECM/PCM connector A (32P)
and body ground with theECM/PCM connectors connected ('99 - 00 models).
Rapdir open in tho wi?e botwaonthe A/C pr..-ruro lwitch rnd th.ECM/PCM.
Check lor loo3e wires or ooolconnections at the ECM/PCMconnectoB A l32P) and at the A/Cpressure switch 2P connector, lfthe connections are good, substi-tute a known-good ECM/PCM,and recheck. lf the svmptom/indication goos away, repbce theoriginal ECM/PCM.
31501E91011
tat6l11E1921222321
BLU/RED
22-16

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

Ftom page 22 18
Check tor an open in the wire:1. Turn the ignition switch OFF,then disconnect the iu mper
2. Remove the center dashboardlower cover lsee section 20),
and disconnect the heater con'
trol panel 14P connector.
3. Turn the ignition switch ON (ll).
4. Measure the voltage betweenthe No. 11 terminal and bodyground.
Repair op6n in the wire bstween
the A/C th€rmostat and th6 hoater
control panel.
Check lor an open in the wire:
1. Turn the ignition switch OFF.2. Disconnect the heater Ian
switch 6P connector,3. Check for continuity between
the No. 14 terminal of theheater control panel 14P con_nector and the No.6 terminalof the heater fan switch 6P con-nector.
Repair open in the wiro betweGnthe heal.r control Panel and theheater fan switch.
Check for an open in thG wire:Check for continuity between theNo. 1 terminal of the heater lanswatch 6P connector and bodYground.
Chock tor an open in tho wir€
between the heater lan switch
and body ground. lf the wire is OK,check for poor ground at G401 sndG402.
ls there continu;ty?
ReDlace the heater tan switch.ls the heater fan switch OK?
Check for loose wiaes or poor
connections at the heater controloanel 14P connoctor and hoetertan 3witch 5P conn€clor and atthe A/C thermostet 3P connec-tor. ll the connections are good,
raplace the heator control Panel.
r'oA - qe m^.lalal
HEATER CONTROL PANEL lilP CONNECTOR
tra6
7II'o lx't1121314
BLU/RED
Wire side of female terminals
HEATER CONTROL PANEL 1'P CONNECTOR
Wire side of female terrninals
HEATER FAN SW]TCH 6P CONNECTOR
Wire side of female terminals
(cont'd)
12;--?45
7I10X'll121314
GRN
123
a56GRN
22-19

Troubleshooting
('99 00 models)
From page 22 18
Check lor an open in the wire:1. Turn the ignition switch OFF,then disconnect the ju mper
2. Disconnect the heater controlpanel 20P connector.3. Turn the ;gnition switch ON{

i.4. Measure the voltage betweenthe No. 11 terminal of theheater control panel 20P con-nector and body ground.
Ropai. opan in tho wira batwaonthe A/C thermostat and thehoater control oanol.ls there battery voltage?
Check the push switch:1. Turn the ignition switch OFF.2. Disconnect the push switch12P connector.3. Check for continuity betweenthe No. I and No. 10 terminalsof the push switch 12P con-nector with the A/C switch ON.
Check for loose wi.es or poor
connections el the hgater controlpanel 20P connector and pushswitch 12P connector and at theA/C thermostat 3P connector. Ittha connections are good, substi-tute a known-good heatea con-trol pan€|, and recheck. lf thesymptom/indication goe3 away,replace lhe original healer con-trol oan€|,
HEATER CONTROL PANEL anP CONNECTOR
Wire side of temale terminals
PUSH SW]TCH 12P CONNECTOR
Wire side of female terminals
,/1,/156
7819t01112
I
I
I

A/C ThermostatRelays
Test
1.Remove the Ay'C thermostat (see page 22-29).
Connect baftery power to the No. 3 terminal, ground
the No. 2 terminal, and connect a test light between
the No. 1 and No. 3 terminals.
NOTEr Use a 12 V,3 W- l8 W test light.
Dip the IVC thermostat into a cup filled with ice water,
and check the test light.
Serp6ntine-type evaporator
The light should go off at 36 - 39'F {2 - 4"C} or less, and
should come on at 39 - 41"F (4 - 5"C) or more
Laminale-type evaporator
The light should go off at 39 - 43'F (4 - 6'C) or less, and
should come on at 43 - 45"F (6 - 7'C) or more
lf the light doesn't come on and go off as specified,
replace the PVC thermostat.
12V,3W-18W
Test
There should be continuity between the No, 1 and No.2
terminals when power and ground are connected to the
No.3 and No. 4 terminals, and there should be no conti-
nuitv when Dower is disconnected.
2
Condenser fan relay
Compressor clutch relay
a
a
,I Ib
In Io'r I
t\----,'
t:n
,,l[4..-.
22-21

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