2002 HONDA CIVIC heating

Heating and Air Conditioning
Condenser Fan Circuit Troubleshooting
NOTE: lf neither the condenser fan nor the radiator fan
work, go to Radiator and Condenser Fans Common
Circuit Troubleshooting (see page 21-29).
1. Check the No. 1 (20A) fuse in the under-hood
fuse/relay box, and the No. 14 (10A)fuse in the
under-dash f use/relay box.
Are the tuses OK?
YES-Go to step 2.
NO Replace the fuse(s), and recheck. t
2. Remove the condenser fan relay from the
under-hood fuse/relay box, and test it(see page 22-51).
ls the relay OK?
YES Go to step 3.
NO- Replace the condenser fan relay.l
3. Measure the voltage between the No, 2 terminal of
the condenser fan relay 4P socket and body ground.
CONDENSER FAN RELAY ilP SOCKET
ls thete battery voltage?
YES-Go to step 4.
NO-Replace the under-hood fuse/relay box.l
21-28
4. Connect the No. landNo.2terminalsof the
condenser fan relay 4P socket with a jumper wire.
CONDENSER FAN RELAY itP SOCKET
JUMPER WIRE
Does the condenser lan tun?
YES-Go to step 5.
NO Go to step 8.
5. Disconnect the jumper wire.
6. Turn the ignition switch ON (ll).
7. Measure the voltage between the No, 3 terminal of
the condenser fan relay 4P socket and body ground.
ls there battery voltage?
YES Replace the under-hood fuse/relay box.t
NO-Repair open in the wire between the No. 14
fuse in the under-dash fuse/relay box and the
condenser fan relay.l
Disconnect the jumper wire.
CONDENSER FAN FELAY 4P SOCKET
r-,_-l
12 |
Flr\----1--rl
IELK/YEL
d,
I

Heating and Air Conditioning
Radiator and Condenser Fans
Common
(cont'dl
Circuit Troubleshooting
9. Using a Backprobe Set, measure the voltage
between the No. 6 terminal of ECN4 connector B
{24P) and body ground with the ECM connectors
connecteo.
ECM CONNECTOR B {24P}
ls there battery voltage?
YES UDdate the ECM if it does not have the latest
so{tware, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM.I
NO Repair open in the wire between the radiator
fan relay, the condenser fan relay and the ECM. t
Wire side of female terminals
21-30
Compressor Clutch Circuit
Troubleshooting
1. Check the No. 1 (20A) fuse in the under-hood
fuse/relay box, and the No. 14 {10A)fuse in the
under-dash fuse/relay box.
Are the tuses OK?
YES Go to step 2.
NO Replace the fuse(s), and recheck.I
2. Check the engine coolant temperature, the throttleposition sensor, and the idle speed (use the Honda
PGM Tester PGM-Fl data list if possible).
ls the coolant temperaturc above nomal, the
throttle position sensor rcading too high, or the
idle speed too low?
YES Troubleshoot and repair the cause of the
high engine coolant temperature, high throttle
position sensor reading, or low idle speed.l
NO-Go to step 3.
3. Remove the compressor clutch relay from the
under-hood fuse/relay box, and test it (see page 22-
51 ).
ls the relay OK?
YES Go to step 4.
NO Replace the compressor clutch relay.I
4. Measure the voltage between the No. 2 terminal of
the compressor clutch relay 4P socket and body
ground.
\
COMPfiESSON CLUTCH BELAY 'P SOCKET
ls there battery voltage?
YES Go to step 5.
NO Replace the under-hood fuse/relay box.I

Heating and Air Conditioning
Compressor Clutch Circuit
Troubleshooting (cont'dl
16. Check for continuity between the No. lterminal of
the compressor clutch relav 4P socket and the No. l
terminal of the compressor clutch 1P conneclor.
COMPRESSON CLUTCH RELAY 4P SOCKET
COMPRESSOR CLUTCH 1P CONNECTORTerminal side of male terminals
ls therc continuity?
YES-Check the compressor clutch clearance, the
thermal protector, and the compressor clutch field
coil (see page 21-48).I
NO-Repair open in the wire between the
compressor clutch relay and the compressor
clutch.l
21-32
A/C Pressure Switch Circuit
Troubleshooting
'1. Turn the ignition switch ON {ll).
2. Turn the blower switch on, and check for blower
motor operatron.
Does the blower motor run on all speeds?
YES Go to step 3.
NO Troubleshoot the blower motor circuit (see
page 21-20).
3. Turn the ignition switch OFF.
4. Disconnect heater control panel connectorA ('14P).
5. Turn the ignition switch ON (ll).
6. Measure the voltage between the No, 4 terminal of
heater control panel connector A {14P) and body
grou nd.
HEATER CONTROL PANEL CONNECTOR A (I4P}
1.
ls there battety voltage?
YES Go to step 7.
NO-Go to step 9.
Stan the engine.
Wire side of female termina's

Heating and Air Conditioning
Air Mix Control Motor Test
1. Disconnect the 5P connector from the air mix
control motor.
2. Connect battery powertothe No. l terminal ofthe
air mix control motor, and ground the No. 2
terminal; the air mix control motor should run, and
stop at Max Cool. lf it doesn't, reverse the
connections;the air mix control motor should run,
and stop at Max Hot. lf the air mix control motor
does not run, remove it. then check the air mix
control linkage and door for smooth movement.
. lf the linkage and door move smoothly, replace
the air mix control motor.. lf the linkage ordoorstickor bind, repairthem as
needed.. lf the air mix control motor runs smoothly, go to
step 3.
AIR MIX CONTROL MOTOR
3.
4.
Measure the resistance between the No. 4 and
No. 5 terminals. lt should be between 2.1 k to
3.9 kQ.
Reconnect the air mix control motor 5P connector,
then turn the ignition switch ON {ll).
Using the Backprobe Set, measure the voltage
between the No. 3 and No. 4 terminals.
Max Cool about 1V
Max Hot about 4 V
lf either the resistance or voltage readings are not
as specified, replace the air mix cotrol motor.
21-34
Air Mix Control Motor Replacement
1.Remove the under-dash fuse/relay box (see page
22-491.
Disconnect the 5P connector {A) from the air mix
control motor (B). Remove the self-tapping screws
and the air mix control motor from the heater unit.
Remove the rod (C) from the arm (D) of the air mix
controi motor.
Install the motor in the reverse order of removal.
After installation, make sure the motor runs
smoothly.
3.
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,.,:l'

Heating and Air Conditioning
Recirculation Control Motor Test
1. Disconnect the 5P connector from the recirculation
control motor.
Incorrectly applying power and ground to
the recirculation control motor will damge it.
Follow the instructions carefullv.
2. Connect batterv oower to the No. 5 terminal ofthe
recirculation control motor, and ground the No. 1
and No. 2 terminals; the recirculation control motor
should run smoothly. To avoid damaging the
recirculation control motor, do not reverse power
and ground. Disconnect the No. 1 or No. 2
terminals from ground; the recirculation control
motor should stop at Fresh or Recirculate. Don't
cycle the recirculation control motor {or a long time.
RECIRCULATION CONTROL MOTOR
lf the recirculation control motor does not run in
step 2, remove it, then check the recirculation
control linkage and doors for smooth movement.
. lfthe linkage and doors move smoothly, replace
the recirculation control motor.. lf the linkageordoorsstickor bind, repairthem
as neeoeo.
21-36
Recirculation Control MotorI
Replacement
1.Remove the ECM (see page 11-4).
Remove the relay mount bracket bolt. and move
the relays out of the way,
Disconnect the 5P connector (A) from the
recirculation control motor (B), Remove the self-
tapping screws and the recirculation control motor
from the blower unit.
Installthe motor in the reverse order of removal.
Make sure the pin on the motor is properly
engaged with the linkage. After installation. make
sure the motor runs smoothly.
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Heating and Air Gonditioning
a
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Power Transistor Test
1. Disconnect the 4P connector from the power
Iranslslor.
2, Measure the resistance between the No. 1 and
No. 2 terminals of the power transistor. lt should be
about '1.4 1.5 kQ.
. lf the resistance iswithln the specifications, go to
step 3.. lf the resistance is notwithin the specifications,
replace the power transistor.
POWER TRANSISTOB
Carefully release the lock tab on the No. 4 terminal(BLUI/EL) (A) in the 4P connector, then remove the
terminal and insulate it from body ground.
(To 12 V power source on vehicle)
Reconnect the 4P connector to the power transistor.
Supply 12 volts to the No. 4 cavity with a jumper
wire.
Turn the ignition switch ON (ll), and check that the
blower motor runs.
. lf the blower motor does not run, replace the
power rranstsror.. lf the blower motor runs,the powertransistoris
oK.
12 V power source on vehicle)
21-38
1.
Heater Control Panel and Push
Switch Assembly Removal and
Installation
Remove the center panel (see page 20-62).
Remove the dials (A), then remove the self-tapping
screws and the heater control panel (B)from the
center panel (Cl. Remove the self-tapping screws
and the push switch assembly (D)from the center
panel.
lnstall the control panel and push switch assembly
in the reverse order of removal. After installation,
operate the control panel controls to see whether it
worKs propeny.
Run the self-diagnosis function to confirm that
there are no problems in the system (see page 21-
8).
3.
4.

Heating and Air Gonditioning
Blower Unit Removal and Installation {cont'd}
Remove the steering hanger beam bracket cover
from the right side of the glove box opening, then
remove the bolts and the olove box frame.
1.
8.
9.
Remove the ECM (see page 11-4).
Remove the EPS control unit (see page 17-67).
Disconnect and remove the PGM-Fl main relays
and bracket assembly, then remove the ECM
bracket.
Disconnect the connectors {A) from the blower
motor and the power transistor, then remove the
wire harness clips (B) and the connectors (C).
Remove the self-tapping screws and the bracket (D).
A
21-40
10. Disconnectthe connector {A) from the recirculation
control motor, then remove the wire harness clip
{B). Remove the mounting bolts, the mounting nuts
and the blower unit (C).
6x 1.0 mm I9.8 N.m (1.0 kgt.m,7.2 tbt.ftl
6x1.0mm9.8 N.m (1.0 kgf.m,?.2 tbf.ft)
11.
14.
Installlhe unit in the reverse order of removal.
Make sure that there is no air leakage.
Reconnect the negative battery terminal.
Do the engine control module (ECM) idle learn
procedure {see page 11-139).
Enter the anti-theft code for the radio, then enter
the customer's radio station presets.
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'13.

Heating and Air Gonditioning
a
1.
Evaporator Core Replacement
Recover the refrigerant with a recovery/recycling/
charging station (see page 21-53).
Remove the bolt, then disconnect the suction line
(A) and the receiver line (B)from the evaporator
core.
6x10mm9.8 N.m (1.0 kgt.m, 7.2lbf.ft)
Remove the blower unit (see page 21-39).
Remove the self-tapping screws and the expansion
valve cover.
21-42
5. Carefully pull out the evaporator core without
bending the pipes.
Installthe core in the reverse order of removal, and
note these items.
. lfyou're installing a new evaporator core, add
refrigerant oil (KElHlN SP-]0) (see page 21-6).. Replace the O-rings with new ones at each fitting,
and apply a thin coat of refrigerant oil before
installing them. Be sure to use the correct O-rings
for HFC-134a (R-'134a) to avoid leakage.. lmmediatelyafter usingthe oil, reinstallthecap
on the container, and seal it to avoid moisture
absorotion.. Do not spill the refrigerant oil on the vehicle; it
may damage the paint. lf the refrigerant oil
contacts the paint, wash it off immediately.. Charge the system (see page 21-55).
6.