air mix control motor HONDA CIVIC 2003 7.G Workshop Manual

cont'
ItemMeasuremeniOualificationSpecilicationSTEERINGTypeElectric, Power assisted rack and pinion
Overall ratio15.1Turns,lock to-lock
Steering wheel diameter360 mm (14.2 in)SUSPENSIONTypeIndependent srrul with stabiliTer. coil springRearDouble wishboneShock absorberFrontTelescopic, hydraulic. nitrogen gas-frlled
RearTelescopic, hydraulic, nitrogen gas,filledWHEEL
ALIGNMENT
CamberFront0"00'
Bear0.45'
CasterFront1'33'TotaltoeFront0 mm (0 in.)
RearIn 2 mm (1/16 in.)BRAKESType of service brakeFrontPowerassisted self-adjusling ventilated disc
BearPower-assisted self-adjusting solid discType of parking brakeMechanical actuating, rear wheelsPad friction surface areaFront45 cm'(7.0 sq in.)x2
Rear28 cm'(4.3 sq in.) x 2TIRESSize offront and reartiresPl95/60 815 88VSize o{ spare tireT125r0 D15 95MAIR
CONDITIONING
CompressorTypeScroll
Number of
cylinders
Capacity85.7 m015.23 cu in.)/rev.
Maximum speed12,000 rpm
Lubricant capacity130 m0 {4 1/3 floz)
LubricanttypeSP-10 (P/N 38897'P13-A01AH or38899-P13 A01)CondenserTypeCorrugated finEvaporatorTvpeCorrugated fin
BlowerTypeSirocco fan
Motor type220 Wl12 V
Speed control4 Speeo
Maximum capacity480 m" 116.900 cu ft)/hTemperature controlAirmixtype
Compressor clutchTvpeDry, single plate, poly-V belt drive
Electricalpower
cons!mptron at
68"F (20.C)
42 W maximum at 12 V
RefrigerantTypeHFC 134a (R-134a)
Capacity500 550 g (17.6 19.4 oz)
Design Specifications
C
aL
2-12
../ a

21-2
z t-'5
z t-o
z t-o
21-8
21-9
21-10
21-11
21-14
z t- to
HVAC (Heating, Ventilation, and Air Gonditioningl
Heating and Air Conditioning
SpecialTools
Comoonent Location lndex ........
A/C Service Tios and
Precautions
A,/C Refrigerant Oil
ReDlacement
General Troubleshooting
lnformation
DTC Troubleshooting Index .......
Symptom Troubleshooting
1ndex..............
System Description .....................
Circuit Diagram
DTC Troubleshooting ..................
Recirculation Control Motor
CircuitTroubleshooting .......... 21-25
Heater Control Power and Ground
Circuits Troubleshooting ........ 21-27
Condenser Fan Circuit
Troubleshooting ...................... 21-28
Radiator and Condenser Fans
Common Circuit
Troubfeshooting ...................... 21-29
Compressor Clutch Circuit
Troubleshooting ...................... 21-30
A,/C Pressure Switch Circuit
Troubleshooting ...................... 21-32
Air Mix Control Motor
Test and Reolacement ............. 21-34
Mode Control Motor
Test and Replacement ............. 21-35
Recirculation Control Motor
Test and Reolacement ............. 21-36
Evaporator Temperature Sensor
Reolacement and Test ............. 21-31
Power Transistor Test ................. 21 -38
Heater Control Panel and
Push Switch Assemblv
Removal and Installation ........ 21-38
Dust and Pollen Filter
Reolacement ..21-39
Blower Unit Removal and
lnstallation ...... 21-39
Blower Unit Comoonents
ReDlacement ............................ 21-41
Evaporator Core
Reolacement ..21-42*Heater Unit/Core
ReDlacement ..21-43
Heater Valve Cable
Adjustment .....21-46
CompressorReplacement .......... 21-47
Comoressor Clutch Check .......... 21-48
Comoressor Clutch Overhaul ..... 21-49
Compressor Thermal Protector
Reo1acement ............................ 21-51
Comoressor Relief Valve
Reolacement ............................ 21-51
Condenser Reolacement ............ 21-52
Refrigerant Recovery .................. 21-53
System Evacuation ...................... 21-54
System CharginS ......................... 21-55
Refrigerant LeakTest .................. 21-56
A,/C Svstem Tests ........................ 21-57

HEATER UNIT/COREBeplacement, page 21-43
BLOWEN UNITRemoval and Installation, page 21-39
HEATER VALVE CABLEAdjustment, page 21-46
BLOWER UNIT COMPONENTSReplacement, page 21-41
DUSTAND POLLENFILTERReplacement, page 21'39
RECIRCULATION CONTROL MOTORTest, page 21-36Replacement, page 21-36
MODE CONTROL MOTORTest, page 21-35Replacement, page 21-35
AIR MIX CONTROL MOTORTest, page 21'34Replacement, page 21'34
POWER TRANSISTORTest, page 21-38
HEATER CONTROL PANELRemovaland Installation, page 21 38
PUSH SWITCH ASSEMBLYRemoval and Installation, page 21'38EVAPORATOR TEMPERATURESENSORReplacement, page 21-37Test, page 21-37
21-5

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
DTC Troubleshooting
DTC 7: An Open in the Air Mix Control Motor
Circuit
1. Test the air mix control motor {see page 2'l-341.
ls the air mix control motor OK?
YES-Go to step 2.
NO-Replace the air mix control motor.l
2. Disconnect the air mix control motor 5P connector.
3. Disconnect heater control panel connectors A {14P)
and B (22P).
4. Check for continuity between the following
terminals of heater control panel connectors A
(14P) and B (22P) and the air mix control motor 5P
connector,
14P: 5P:
No. 1 No.5
No.2 No.4
No.3 No.2
No.9 No. 1
22P: 5P:
No.6 No.3
Wire side ol lem.letehi.6ls
ls there continuity?
YES-Check for loose wires or poor connections at
heater control oanel connectors A (14P) and B (22P)
and at the air mix control motor 5P connector. lf the
connections are good. substitute a known-good air
mix control motor, and recheck, lf the symptom/
indication goes away, replace the original air mix
control motor. lf the symptom/indication continues,
substitute a known-good heater control panel, and
recheck. lf the symptom/indication goes away,
replace the original heater control panel.l
NO Repair any open inthewire(s) ketweenthe
heater control panel and the air mix control
motor.l
21-16
DTC 8: A Short in the Air Mix Control Motor
Circuit
1. Test the air mix control motor(see page 21-341.
ls the ait mix control motor OK?
YES-Go to step 2.
NO-Replace the air mix contorol motor.I
2. Disconnect the air mix control motor 5P connector.
3. Disconnect heater control panel connectors A (14P)
and B (22P).
4. Check for continuity between body ground and
heater control panel connector A (14P) terminals
No. 1, 2, 3, and 9 individually, and between body
ground and heater control panel connector B (22P)
terminal No. 6.
HEATERCONTROL PANEL CONNECTOR A {I4PI
HEATER CONTFOL PANELCONNECTOR B I22P1
ls therc continuity?
YES-Repair any shortto body ground ln the
wire(s) between the heater control panel and the air
mix control motor.l
NO-Go to step 5.
Wire side of female terminals
Wire side oilema e lerminals

5. Turn the ignition switch ON (ll), and check the same
terminals for voltage.
HEATER CONTROL PANEL CONNECTOR A {14PI
HEATER CONTROL PANEL CONNECTOR B I22PI
Wire side of female terminals
ls there any voltage?
YES-Repair any short to power in the wire(s)
between the heater control panel and the air mix
control motor. This short may also damage the
heater control panel. Repair the short to power
before replacing the heater control panel.l
NO Substitute a known-good air mix control
motor, and recheck. lf the symptom/indication goes
away, replace the original air mix control motor. lf
the symptom/indication continues, substitute a
known-good heater control panel, and recheck. lf
the symptom/indication goes away, replace the
original heater control panel.I
Wire side of female terminals
DTC 9: A Problem in the Air Mix Control
Linkage, Door, or Motor
1, Test the air mix control motor (see page 21-34).
ls the air mix control motor OK?
YES-Substitute a known-good heater control
panel, and recheck. lf the symptom/indication goes
away, replace the original heater control panel.l
NO-Replace the air mix control motor, or repair
the linkage and door.l
21-17

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'

Heating and Air Conditioning
Heater Unit/Core Replacement (cont'd)
8. Remove the dashboard {see page 20-66).
9. Disconnectthe connectors (A) from the blower
motor, the recirculation control motor, the mode
control motor, and the power transistor, then
remove the wire harness clips (B) and the
connector (C). Remove the self-tapping screws and
the bracket (D).
Disconnect the connectors (A) from the evaporator
temperature sensor and the air mix control motor,
then remove the wire harness clips (B) and the
connector (C). Remove the self-tapping screw and
the cover (D). Disconnect the heater valve cable (E).
10,
7t,
21-44
11. Remove the mounting bolts, the mounting nuts,
and the heater unit.
Remove the self-tapping screws and the expansion
valve cover (A). Carefully pull out the evaporator
core (B) so you don't bend the inlet and outlet pipes.
Remove the grommet (C), then remove the self-
tapping screws and the flange cover (D). Bemove
the self-tapping screws and the pipe cover (E), then
carefully pull out the heater core (F) so you don't
bend the inlet and outlet oioes.
@
5x 1.0 mm9.8 N.m11.0 kgl m,7.2 tbf.ftl
12.

A/C Wire Harness
Connoctor or TerminalRelCavitiesLocationConnec'tstoNotesAir mix control motorBlower motorEvaporator temperature sensorMode control motorPowertransistorRecirculation control motorc851
c852
c853
I283411
6
5
52210
51
21
,]
Under maddle of dashUnder right side of dashUnder middle of dashUnder right side of dashUnder right side of dashUnder right side of dashUnder middle ol dash
Under middle ofdash
Under middle o{ dash
Engine compartment wireharness (see page 22-18)Dashboard wire harness A{see page 22 26iDashboard wire harness Alsee oaoe 22-261
22-43

Service Manual lndex
)s
NOTE: Referto the lollowing listto look up A/C Pressure Switch CircuitDTCS, symptoms, fuses, connectors, wire Troubleshooting ......... ...-.-....-...-.-.-....-..21-32 Bharnesses, specifications, maintenanceschedules, and general serviceinlormation:
DTC Troubleshooting Indexes
A/C Signal CircuitTroubleshooting.........................-...... 11-'133 Back-up Light SwitchTest .......................................................... 13'3A/F lAir Fuel Ratiol SensorABS/TCS Components ........................ 19-34 Replacement ....................................... 1 1-113 Back-up Li9ht3EPS Components ................................. '17-22 Circuit DiagramFueland Emissions11-i A-Dillar Corner Trim
ABS Indicator Circuit
Heating/Ventilation ................................ 21-9 Replacement ...............-.....-..............-.... 20,96 Ball Joint BootssRS ........................................................ 23-28Replacement ......
... 19-52 Ball Joints
22-75
18 16
Remova1.............-.......... . ...........18-10Symptom Troubleshooting Indexes TroubleshootingABS/TCSComponents........................ 19 35Cruise Control System ..........................4 38 ABS Modulator-contml UnitEPS Components ................................. 17-23 Bemoval/lnstallation ............................ 19-57 BettervFan Controls10,12
Accessory Powor Socket Front
Blowor Pow€r Transistor
.......22 50
Blower UnitRemoval/lnstallation ............................ 21-39
Fuel and Em issions .............................. 11-10 ABS/TCS ComoonentsHeating/Ventilation..............................21 10 Component Location Index ................. 19-30 Beverage Holder
SRS ........................................................ 23'30 CircuitDiaqram.......................... 19'42Blower MotorReplacement .....21 41
21-38
Power 0istribution ...............................22-46 TesVReplacement .............................. 22'149Under-dash Fuse/Relay Box ............... 22 45Under-hood Fuse/Belay Box ...............22 44 Accessory Power Sockets
Fuse/Relay lndexes
(to harness)
Connector and Wire Harness lndexesComponent Connectors
Circuit Oiagram .................................. 22-149
Air Cleaner......2214 Rep1acemen1.....................................11-162
Air MixControl MotorMeintenence section .................... Section 3 Replacement ......................................... 21'34 Brake CelipersTest......................21-34 Overhaul19-14,23Gene.al lnlormation section........ Section 1
21.57
Airbag. Driver's
Ahernator FR Signal CircuitTroubleshooting .... .........-..........11 134
AntennaReplacement
Inspection ............................................. 19-24Rep|acement................. .................... 19-25
Bieke Meder Cylinder
Irake Discs
A
Replacement ....................................... 23 1 'l3 Inspection .................... ................... 19-13,22Repair ...........-...................................... 23 1 16Brake Fluid Level SwitchAirbag. Front Passenger's TestBeplacement....................................... 23-1 14AIC Brake LightsComponent Location fndex ...................21-3 Altemator CircuitDiagram....................................22-74Description.....................................-....21'1'l Beplacement ................ ........................... 4 29CircuitDiagram....................................21-14 Overhaul .................................................4-30 Brake Lines and Hoses
19.10
A/C CompressolReplacement .......-...-............................. 21 -41
A/C Compr€ssor ClulchRep1acement......................................... 19-15.........22-103 Inspection ............................................. 19-16Inspecton........Overhaul ..........
A/C CondenserReplacement,.,
21-442l-49 Audio Unit
Replacement
Brake PadsRemoval/lnstallation .. ........................22-100 Inspection/Rep1acement................ 19-11,20A/C Compressor Clutch CircuitTroubleshooting ................................... 21-30 Audio Unit Connector Brake Pedal22101 Adjustment..............19,6ArfC Comoressor Relief ValvcReplacement ..........-...-.......................... 21-51 Audio/Entertainment
A/C Compr$sor Thermal Protector Circuit DiagramReplacement............-............................ 21-51
Component Location In dex .................22-9A Test .......-.............. 22-84Breke Pedal Posilion Switch
Brake Pedal Position Switch Signal Clrcuit11-137
.....21 52
A/C Condenser Fan CircuitTroubleshooting ................... . . . . . .....21-28
)s
Troubleshooting
(cont'd)