2003 HONDA CIVIC service

Front Seat Cover Replacement
For some models: SRS components are located in this
area. Review the SRS component locations (see page
23 13) and the precautions and procedures (see page
23-'14) in the SRS section before performing repairs or
service,
NOTE:. Take care not to tear the seams or damage the seat
covers,. On the passenger's seat with side airbag, do not
touch the OPDS sensor in the seat-back pad, and keep
it away from oil. Oil can corrode the sensor causing it
to fail.. Put on gloves to protect your hands.
Seat-back Cover
Remove the front seat isee page 20-71).
With side airbag: From under the seat cushion,
detach the side airbag connector clip (A), and on
the passenger's seat, detach the OPDS unit
connector clip (B). Release the hook springs (C)
from the seat cushion frame spring {D), then pull
the guide cover (E) back, and remove the wire ties
(F). The passenger's seat is shown, the driver's seat
is svmmetrical except it has no OPDS unit
connector.
'L
2.
3.Fold the seat-back forward.
Release the hooks (A), and unzip the seat-back
cover (B).4.
(cont'd)
20-75

2.
5.
Fuel Fill Door Opener Cable Replacement
SRS components are located in this area. Review the SRS component locations (see page 23-13) and the precautions
and procedures (see page 23-14) in the SRS section before performing repairs or service.
NOTE;. Put on gloves to protect your hands.. Take care notto scratch the body and related parts.
1. Remove these items from the left side of the vehicle:
. Door silltrim {see page 20-50). Rear side trim panel (see page 20-51)
Pullthe carpet back as necessary (see page 20-55).
Disconnect the fuel fill door opener cable (A) from the opener (B) (see step 3 on page 20-109).
Fastener Locations
C >:Cushiontape, 1 D >: Clip, 1E > : Clip, 2
4. KCmodel: Removethe left middle floor cross-member gusset (see page 20-113).
5. Remove the cushion tape {C), and release the cable from the clips (D, E).
6. Removethefuel fill doorlatch (F)fromthe bodybyturning it90'.
7. Remove the fuel fill door opener cable from the vehicle. Take care not to bend the cable
8. Install theopenercableinthereverseorderofremoval,replacethecushiontape,andreplacetheclipifitis
oamageo.
20-107

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

Heating and Air Gonditioning
Component Location Index
SERVICE VALVE{LOW.PRESSUBE SIDEI
EVAPORATOR CORE(Built-in the heater unit)Beplacement, page 21 42
COMPRESSORBeplacement, page 21 47Clutch Check, page 21-48Clutch Overhaul, page 21-49Thermal Protector Check, page 21-48Thermal Protector Replacement, page 21 51Relief Valve Replacement, page 21 51
SERVICE VALVE{HIGH-PRESSURE SIDEI
RECEIVER/DRYER
CONOENSEBReplacement, page 21-52

Heating and Air Conditioning
A/C Service Tips and Precautions
Compressed air mixed with R- 134a forms a
combustible vapor.
The vapor can burn or explode causing serious
injury.
Never use compressed air to pressure test
R-134a service equipment or vehicle air
conditioning systems.
Air conditioning refrigerant or lubricant vapor
can irritate your eyes, nose, or throat.
Be careful when connecting service equipment.
Do not breathe refrigerant or vapor.
The air conditioning system uses HFC-134a (R-134a)
ref rigerant and polyalkyleneglycol (PAG) ref rigerant oil,
which are not compatible with CFC'12 (R-12) refrigerant
and mineral oil. Do not use R-'12 refrigerant or mineral
oil in this system, and do not aftempt to use R 12
servicing equipment; damage to the air conditioning
system or your servicing equipment will result.
Use only service equipment that is U.L.-listed and is
certified to meet the requirements of SAE J2210 to
remove R-134a from the air conditioning system.
lf accidental system discharge occurs, ventilate the
work area before resuming service.
R-134a service equipment or vehicle air conditioning
systems should not be pressure tested or leak tested
with compressed air.
Additional health and safety information may be
obtained from the refrigerant and lubricant
manufacturers.
. Always disconnect the negative cable from the
battery whenever replacing air conditioning parts.
. Keep moisture and dirt out of the system. When
disconnecting any lines, plug or cap the fittings
immediately; don't remove the caps or plugs until
iust be{ore you reconnect each line.' Before connecting any hose or line, apply a few drops
of relrigerant oil to the O-ring.. When tightening or loosening a fitting, use a second
wrench to support the matching fitting.. When discharging the system, use a R-'134a
ref rigerant recovery/recycling/charging station; don't
release refrigerant into the atmosphere.
21-6
A: 130 m0 {4 l/3 tl.oz,4.6 lmp.oz)
],^
A/C Refrigerant Oll Replacement
Recommended PAG oil: KEIHIN SP 10:
. P/N 38897-P l3-A01AH: '120 m0 i4 fl oz). P/N 38899-P13'A01: 40 m0 i1 1/3 fl oz)
Add the recommended refrigerant oil in the amount
listed if you replace any of the following parts.
. To avoid contamination. do not return the oilto the
container once dispensed, and never mix it with other
refrigerant oils.. lmmediately af'ter using the oil, reinstallthe cap on
the container, and seal it to avoid moisture
aosorpron.. Donotspill the refrigerant oil on the vehicle; it may
damage the paint. lf it gets on the paint, wash it off
immediately.
Condenser ...........25 mA \516 tl.oz, 0.9 lmp.oz)
Evaporator ........... 45 m0 (1 113Il.oz, '1.4 lmp.oz)
Line or hose ......... '10 m0 {1/3 fl.oz,0.4 lmp.oz)
Receiver/Dryer .... '10 m0 ('113 fl.oz,0.4 lmp.oz)
Leakage repai r .... 25 m0, 1516 Il oz, 0.9 lmp.oz)
Compressor ......... For compressor replacemenl,
subtract the volume of oil drained
from the removed compressor from
130 m0 (4 1/3fl.oz, 4.6lmp.oz), and
drain the calculated volume of oil
f rom the new compressor: '130 m0
i.4113 fl.oz,4.6 lmp.oz) Volume of
removed compressor = Volume to
drain from new compressor.
NOTE: Even if no oil is drained from
the removed compressor, don't
d rain more than 50 m0 \1 2/3 fl.oz,'1.8 lmp oz)from the new
compressor.
\
REMOVEDCOMPBESSOR
rA
li
\.. rJ
b
I
,lEL.-
"o*t ttu"
NEWCOMPRESSOR
/- a\i tl
r/
\:)-) -/
_ 0L'r:l_
I I I DRAINING_*lH I voLUME

Heating and Air Gonditioning
System Description (cont'dl
The air conditioning system removes heat from the passenger compartment by circulating refrigerant through the
system as shown below.
/
BLOWER FAN
\
\,u
EXPANSION VALVE(Meters the requiredamount of refrigerantinto the evaporator)
A/C PRESSURE SWITCHWhen the refriqerant is below196 kPa (2.0 kgi/cm',28 psi)or above 3,140 kPa (32 kgf/cm'455 psi), the Py'c pressureswitch opens the circuit tothe Py'C switch and stops theair conditioning to protect thecompressor-
RECEIVER/DRYER(Traps debris, andremoves morsturel
APOBATOR TEMPERATURESENSOR
THERMAL PROTECTOR(Opens the compressor clutch circuitwhen the compressot temperaturebecomes too high)
RELIEF VALVE(Relieves pressure at the compressorwhen the pressure is too high)
A/C COMPRESSOR(Suction and comoression)\-^
I HrcH PRESSURE vAPoR
[ '.... -:--l Low PREsSUBE LrourD
tffi Low PREssURE vAPoR
This vehicle uses HFC-134a (R-'134a) refrigerant which does not contain ch lorofluorocarbons. Pay attention to the
following service items:
. Do not mix refrigerants CFC-12 (R-12) and HFC-134a (R-134a). They are notcompatible.. Use onlythe recommended polyalkyleneglycol (PAG ) refrigera nt oil (KElHlN SP '!0) designedfortheR-134a
compressor. Intermixing the recommended (PAG) refrigerant oil with any other retrigerant oil will result in
compressor failu re.. AllAy'C system parts (compressor, discharge line, suction line, evaporator, condenser, receiver/dryer. expansion
valve, O-rings for joints) have to be designed for refrigerant R 134a. Do not exchange with R-'12 parts.
. Use a halogen gas leak detector designed for refrigerant R-134a.. R-12 and R-134a refrigerant servicing equipment are not interchangeable. Use only a recovery/recycling/charging
station that is U.L.-listed and is certified to meet the requirements of SAE J2210 to service R-134a air conditioning
system.. Always recover the refrigerant R-134a with an approved recovery/recycling/charging station before disconnecting
any Ay'C fifting.
/-
CONDENSER(Radiation of heat)
21-12

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

Heater Unit/Core Replacement
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 forthe radio,
then write down the freouencies for the radio's
Dreset buttons.
4.
Disconnect the negative cable from the battery,
Disconnect the suction and receiver lines from the
evaporator core (see page 21-42).
From under the hood, open the cable clamp (A),
then disconnect the heater valve cable (B) from the
heater valve arm (C). Turn the heater valve arm to
the fully opened position as shown
When the engine is cool, drain the engine coolant
from the radiator (see page 10-6).
6. Slide the hose clamps (A) back, the n d isconnect the
inlet heater hose (B) and the outlet heater hose (C)
from the heater core. Engine coolant will run out
when the hoses are disconnected; drain it into a
clean drip pan. Be sure not to let coolant spill on
the electrical parts or the painted surfaces. lf any
coolant spills, rinse it off immediately.
Remove the bolt and the heater valve, then remove
the mounting nut from the heater unit. Take care
not to damage or bend the fuel lines and the brake
lines, etc.
7.
8 x 1.25 mm12 N.m (1.2 kgf.m,8.7lbf.ft)
(cont'd)
21-43