ERS HONDA CIVIC 2003 7.G Workshop Manual

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.
\'
,.,:l'

Mode Control Motor Test
Disconnect the 10P connector from the mode
control motor.
Connect battery power to the No. 1 terminal of the
mode control motor, and ground the No. 2
terminal; the mode control motor should run
smoothly and stop at Defrost. lf it doesn't, reverse
the connections; the mode control motor should
run smoothly and stop at Vent. When the mode
control motor stops running, disconnect battery
power immediately.
'1.
4.
MODE CONTROL MOTOR
3. lfthe mode control motor does not run in step 2,
remove it, then check the mode control linkage and
doors for smooth movement.
. lf the linkage and doors move smoothly. replace
the mode control motor.. lf the linkage ordoorsstick or bind, repairthem
as neeoeo.. lfthe mode control motor runs smoothly, go to
step 4.
Use a digital multimeter with an output of 1 mA or
less at the 20 k Q range. With the mode control
motor running as in step 2, check for continuity
between the No. 4,5,6,7,8, and 9 terminals and
the No. 10 terminal individually. There should be
continuity for a moment at each terminal as the
motor moves past each mode position.
lf there is no continuity for a moment at each
terminal. replace the mode control motor.
Mode Control Motor Replacement
2.
3.
1.Remove the ECM (see page 11-4).
Remove the relay mount bracket bolt, and move
the relays out of the way.
Disconnect the 10P connector {A) from the mode
control motor (B). Remove the self-tapping screws
and the mode control motor from the heater unit.
lnstallthe motor in the reverse order of removal.
lvlake sure the pin on the linkage is properly
engaged with the motor. After installation. make
sure the motor runs smoothly.
4.
21-35

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.
\

Evaporator Temperature Sensor
Replacement
1.Remove the driver's dashboard lower cover (see
page 20-59) and the under cover (see page 20-60).
Remove the under-dash fuse/relay box (see page
22-491.
Disconnect the 2P connector (A) from the
evaporator temperature sensor (B), then remove
the connector clip (C). Remove the self-tapping
screw, and carefully pull out the evaporator
temperature.
4. Install the sensor in the reverse order of removal,
Evaporator Temperature Sensor
Test
l. Dip the sensor in ice water, and measure the
resistance between its terminals
EVAPORATOR TEMPERATURE SENSOR
2.
3.
Terminal side ol male terminals
Then pour hot water on the sensor, and check {or a
change in resistance.
Compare the resistance readings with the
specifications shown in the graph; the resistance
should be within the specifications
RESISTANCEk9
t0
32050 68 86 'F
10 20 30'c
TEMPERATURE
21-37

Heating and Air Gonditioning
a
\
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.

Dust and Pollen Filter Replacement
The dust and pollen filters should be replaced every
30,000 miles (48.000 km) or 24 months whichever
comes first. Replace the filters more often if the air flow
is less than usual.
1. Open the glove box. Remove both glove box stops,
then let the glove box hang down (see page 20 63).
2. Remove the filter lid (A)from the blower unit, then
pull out the first dust and pollen filter (B). Slide the
second filter to the left, and pull it out.
Remove the filter {A) from the housing (B), and
replace the filter.
4. Install the filters in the reverse order of removal.
Blower Unit Removal and
lnstallation
For some models: SRS components are located in this
area. Review the SRS component locations (see page
23-13) and precautions and procedures (see page 23-14)
in the SRS section before performing repairs or service.
1. Make sure you have the anti-theft code for the radio,
then write down the frequencies for the preset
buttons.
2. Disconnect the battery negative cable, and wait 3
minutes before beginning worK.
3. Remove the right kick panel (see page 20-50),
passenger's dashboard lower cover, and the glove
box {see page 20-63).
4. Cut the plastic cross brace in the glove box opening
with diagonal cutters in the area shown. Remove
and discard the plastic cross brace,
Cut heare.
{cont'd)
21-39

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.
\
'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.

13. Installthe heater core and the evaporator core in
the reverse order of removal.
14. Installthe heater unit in the reverse order of
removal, and note these items:
. Do not interchange the inlet and outlet heater
hoses, and installthe hose clamps securely.. Refillthe cooling system with engine coolant (see
page 10-6).. Adjust the heater valve cable (see page 2'l-461.. Make sure that there is no coolant leakage.. Make sure that there is no air leakage.. Refer to evaporator core replacement {see step 6
on page 21-42).. Do the engine control module (ECl\4) idle learn
procedure (see page 11-139).. Enter the anti-theft code for the radio, then enter
the customer's radio station Dresets.
21-45

Compressor 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.
2. Make sure you have the anti-theft code for the radio,
then write down the frequencies for the radio's
preset buttons.
3. Disconnect the negative cable from the battery.
4. Recover the refrigerant with a recovery/recycling/
charging station (see page 21-53).
5. Remove the alternator (see page 4-29).
6. Remove the Ay'C condenser fan assembly (see page
10-10).
7. Disconnectthe compressor clutch connector (A),
remove the bolts, then disconnect the suction line(B) and the discharge line (C)from the compressor.
Plug or cap the lines immediately after
disconnecting them to avoid moisture and dust
contamination.
6 x '1.0 mm9.8 N.m11.0 kgt.m,7.2 tbl.ttl
u1/
(
o
8. Remove the mounting bolts and the compressor.
8 x 1.25 mm22 N.m 12.2 kgf.m.
9. Installthe compressor in the reverse order of
removal, and note these items:
. Before installing the new compressor, check for
metal or other contamination in the line. Replace
any contaminated parts.. lf you're installing a newcompressor, you must
calculate the amount of refrigerant oil to be
removed from it (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,. Use refrigerant oil (KElHlN SP-'10) for HFC-134a
KEIHIN spiral type compressor only.. To avoid contaminatlon, do not return the oilto
the container once dispensed, and never mix it
with other refrigerant oils.. lmmediately after using the oil, reinstallthe 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. lf the refrlgerant oil
contacts the paint, wash it off immediately.. Charge the system (see page 21-55).. Do the engine control module (ECM) idle learn
procedure (see page 11-'139).. Enter the antitheft code for the radio, then enter
the customer's radio station presets.
21-47