2003 HONDA CIVIC RECIRCULATION

DTC Troubleshooting Index
In case of multiple problems, the recirculation indicator will indicate only the DTC with the least number of blinks.
ln case of an intermittent failure, the heater control panel will store the DTC until the ignition is turned off.
DTC {Recirculation
Indication Blinks)
Detection ltemPage
7An open in the air mix control motor circuit(see paqe 21-16)
8A short ln the air mix control motor circuit(see Daoe 21-'16)
9A problem in the air mix control linkaqe, door, or motor(see paqe 21- 17)
10An open or shon in the mode control motor circuit(see oaqe 21-18)
11A problem in the mode control linkage, doors, or motor(see paqe 21191
12A problem in the blower motor circuit(see paqe 21-20)
13A problem in the EEPROM in the heater control panel;
the control oanel must be reolaced
(see page 21-38)
14An ooen in the evaDorator temDerature sensor circuit(see paqe 21-23)
A short in the evaDoralor temoerature sensor circuit(see oaqe 21-241
21-9

Heating and Air Conditioning
{
a
a
SvmptomDiagnostic procedureAlso check for
Recirculation control doors do not
change between Fresh and Recirculate
Recirculation Control Motor
Circuit Troubleshooting (see page
21 251
Cleanliness and tightness of all
connectors
Both heater and Ay'C do not workHeater Control Power and Ground
Circuits Troubleshooting (see
page 21-27)
Blown fuse No. '14 (10A) in the
under-dash fuse/relay box
Poor ground at G501
Cleanliness and tightness of all
conneclors
Condenser fan does not run at all (but
radiator fan runs with the Ay'C on)
Condenser Fan Circuit
Troubleshooting {see page 21-28)
. Poor ground at G301. Cleanliness and tightness of all
connectors
Both fans do not run with the A,/C onRadiator and Condenser Fans
Common Circuit Troubleshooting
(see page 21-29)
Blown fuse No. 1 (20A) and No.4
(20A) in the under-hood fuse/relay
box
Poor ground at G30l
Cleanliness and tightness of all
connectors
Compressor clutch does not engage(both fans run with A,/C on)
Compressor Clutch Circuit
Troubleshootinq (see Daqe 21-30)
Cleanliness and tightness of all
connectors
A/C system does not come on (both
fans and compressor)
Ay'C Pressure Switch Circuit
Troubleshooting (see page 21-32)
Blown fuse No. 1 (20A) and No. 4
(20A) in the under-hood fuse/relay
box
Poor ground at G301
Cleanliness and tightness of all
connectors
\Symptom Troubleshooting Index
\
21-10
!

System Description
Heater Control Panel Inputs and Outputs
CONNECTOR A {r/rP)
CONNECTOR
CONNECTOR
HEATER CONTFOL PANEL CONNECIORS
CONNECTOR B (22P)
W re s de oitema eterm nals
Cavity Wire color_| \ln YAIR MIX POTENTIAL +5V
Sional
OUTPUT2LT GRNSENSOR COMMON GROUNDINPUT3PNK/BLUAIR MIX HOTOUTPUTBLUA,/C PRESSURE SWITCHINPUT5GRNA/ELRECIRCULATEINPUT6GRNA/VHTFRESHINPUT7BLUI/ELPOWER TRANSISTOROUTPUT8BLU/REDBLOWER FEEDBACKINPUTIGRNAIR MIX COOLOUTPUT10YEL/REDMODE DEFOUTPUT11. YEVBTU
YEL/BLK
MODE VENT
REAR WINDOW DEFOGGER RELAY
OUTPUT
INPUTBLKGROUNDOUTPUT14B LK/YELlG2 (Power)INPUT
Bon
CavityWire colorSiqnal1--T
2
3BLIVREDREAR WINDOW DEFOGGER SWITCH LEDINPUT
4LT GRNA./C SWITCH LEDINPUT
5LT GRN/BLKRECIRCULATION CONTROL SWITCH LEDINPUT
6PNVBLKAIR MIX POTENTIALOUTPUT
7BRNEVAPORATOR TEIMPERATURE SENSOROUTPUT
8
9
10
GAUGE ASSEMBLYal' 'TDr ri11RED
RED/BLKTAILLIGHTS RELAYINPUT
14BLUREAR WINDOW DEFOGGER SWITCHINPUTicLT GRN/REDA/C SWITCHINPUT16YEVREDRECIRCULATION CONTROL SWITCHINPUT17YEUGRNMODE 4OUTPUT18WHT/BLUMODE 3OUTPUT19RED/BLUMODE 2OUTPUT20RED/YELMODE 1OUTPUTBRN^,^/HTIGN (PowedOUTPUT22R E DA/r'HT(Not used)
(cont'd)
21-11

3.
Recirculation Control Motor Circuit Troubleshooting
1. Check the No. 14('10A)fuse inthe under-dashfuse/
relay box.
ls the f use OK?
YES Go to step 2.
NO- Replace the fuse, and recheck.l
2. Disconnect the recirculation control motor 5P
conneclor.
Turn the ignition switch ON (ll).
lvleasure the voltage between the No. 5 terminal of
the recirculation control motor 5P connector and
body ground.
RECIRCULATION CONTROL MOTOR5P CONNECTOR
7.
Wire side of female terminals
ls there battery voltage?
YES Go to step 5.
NO- Repair open in the wire between the No. 14
fuse in the under-dash fuse/relay box and the
recirculation control motor .l
Turn the ignition switch OFF.
Testthe recirculation control motor {see page 21-
36),
ls the recirculation control motor OK?
YES Go to step 7.
NO- Replace the recirculation control motor, or
repair the linkage and doors.I
Disconnect heater control panel connector A (14P).
5.
6.
8. Check for continuity between the No. 5 and No. 6
terminals of heater control panel connector A (14P)
and body ground individually.
HEATER CONTROL PANEL CONNECTOR A I14P)
Wire side of female terminals
ls there continuity?
YES Repair any shortto body ground in the
wire(s) between the heater control panel and the
recirculation control motor.l
NO-Go to step 9.
9. Turn the ignition switch ON (ll), and check the same
wires for voltage.
HEATER CONTROL PANEL CONNECTOR A Il4PI
Wire side of lemale terminals
ls therc any voltage?
YES Repair any shonto power in the wire(s)
between the heater control panel and the
recirculation control motor. This shon may also
damage the heater control panel. Repair the shon
to power before replacing the heater control
pa nel. I
NO-Go to step 10.
{cont d r
21-25

Heating and Air Conditioning
Recirculation Control Motor Circuit Troubleshooting (cont'd!
10. Turn the ignition swirch OFF.
11. Check for continuity between the following
terminals of heater control panel connector A ( 14P)
and the recirculation control motor 5P connector.'l4Pt 5P:
No.5 No. 1
No.6 No.2
HEATER CONTROL PANEL CONNECTOR A {14P}Wire side ol temale terminats
RECIRCULATION CONTROL MOTOR 5P CONNECTORWire side ol lemale terminals
ls there continuity?
YES Check for loose wires or poor connections at
heater control panel connector A ( 14P) and at the
recirculation control motor 5P conneclor. lf the
connections are good, substitute a known-good
heater control panel, and recheck. lf the symptom/
indication goes away, replace the original heater
control panel,I
NO Repair any open in the wire{s) between the
heater control panel and the recirculation control
motor.l
21-26

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.
\

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.

Blower Unit Components Replacement
Nole these items when overhauling the blower unit;
' The recirculation control motor (A), the power transistor (B), the blower motor (C), and the dust and pollen filtefs (D)
can be replaced without removing the blower unit.. Before reassembly, make surethatthe recirculation control linkage and doors move smoothly.. After reassembly, make surethe recirculation control motorruns smoothly (see page 2j-36).
A
21-41