2003 HONDA CIVIC fuel pressure

EVAP System
EVAP Two Way Valve Test
Special Tools Required. Vacuum pump/Gauge,0-30 in. Hg
A973X-041-XXXXX. Vacuum/Pressure cauge.0-4 in. Hg 07JAZ-0010008
1. Remove the fuelfill cap.
2. Disconnect the vapor line from the EVAP two wayvalve (A). Connect it to a T-fitting (B) from thevacuum gauge and the vacuum pump as shown,
07JAZ-0010008
Apply vacuum slowly and continuously while
watching the gauge. The vacuum should stabilize
momentarily at 0.8 2.1 kPa (6 16 mmHg,
0,2 0.6 in.Hg).
lf the vacuum stabilizes {valve opens) below 0.8 kpa(6 mmHg,0.2 in.Hg) or above 2.1 kPa (16 mmHg,
0.6 in.Hg), install a new valve and retest.
11-186
4. Move the vacuum pump hose from the vacuumfitting to the pressure fitting, and move the vacuumgauge hose from the vacuum side to the pressure
side (A) as shown.
Slowly pressurize the vapor line while watching thegauge. The pressure should stabilize momentarilV
above 1.0 kPa (8 mmHg, 0.3 in.Hg).
. lfthe pressure momentarily stabilizes (valve
opens) above 1.0 kPa (8 mmHg,0.3 in.Hg), thevalve is OK.. lf the pressure stabilizes below 1.0 kPa (8 mmHg,
0.3 in.Hg), install a new valve and retest.

FuelTank Vapor Control Valve Test
Special Tools Required
Vacuum Pump/Gauge, 0-30 in. Hg A973X-041-XXXXX
Float Test
1. Make sure the fuel tank is less than half full.
2. Remove the fuel fill cap to relieve fuel tank
pressure, then reinstall the cap.
3. Disconnect the fuel tank vapor recirculation tube
{A), and connect a vacuum PumP to it.
Plug the line (B).
Apply vacuum to the fuel tank vapor recirculation
tuDe.
lf the vacuum holds, replace the fuel tank vapor
control valve (see page 11-189).
lf the vacuum does not hold, the float is OK. Do
the valve test.
5.
A973X-041-XXXXX
Valve Test
1. N4ake sure the fuel tank is less than half full
2. Remove the fuel fill cap.
3. Disconnect the fuel tank vapor signal tube (A).
Disconnect the vacuum hoses (A) from the EVAP
canister (B), then plug the ports with plugs (C)4.
A973X-O41-XXXXX
5. Disconnect the vacuum hose (D) from the EVAP
canister vent shut valve (E), and connect a vacuum
pump to the vacuum hose.
6. Pump the vacuum pump 80 times.
. lf the vacuum holds, goto steP 7.. lf the vacuum does no1 hold, go to step 10.
(cont'd)
11-187

Gonnectors and Harnesses
a
Floor Wire Harness {Rear side}(cont'dl
Cargo areaDriver's door switchEVAP emission bypass solenoid valveEVAP emission control canister ventshut valveFuel pump/sending unitFuel tank pressure sensorLeft back-up lightLeft rear ABS wheel sensorLeft rear side marker lightLeft rear speakerLeft rear turn signal lightLeft side seat belt tensionerLeft taillighVbrake lightNoise condenser (rear windowdefogger)Noise condenser (rear window wiper)Passenger's door switchRear window wiper intermiftentcontrolunitRight back-up lightRight taillighvbrake tightRight rear turn signal lightBight rear ABS wheel sensorRight rear side marker lightRight rear speakerRight side seat belt tensioner
c554
Fueltank
FueltankFueltankLeft taillightLeft rear offloorBehind left side of rear bumperLeft quarter panelLefttaillightLeft B-pillarLeft taillightRight quarter panel
Right quarter panelRight B pillarRight q uarter panel
Right tai ightRight taillightRight taillightRight side of cargo area
side of cargo areaLeft B pillarFueltank
Right quaner panel
6224
I32512642A527'13
181011
222021151912117
I
2122
5322222232
232222212
12
2120
Behind right side of rear bumperRight quaner panelRight B-pillarRight quaner panelHatch wire harness (see page22 39)Hatch wire harness (see page
rear seal bdcl Bodv ground vta
Right side of cargo area Body ground via floor wire
Connector to Harness Index (cont'dl
22-36

Ground Distribution
Ground to Components Index
GroundComponent or circuit qrounded
Batterv, Transmission housinq
E ngine
G 101ECM (PG is BLK; LG is BRN/YEL)
BLK: IAC valve, lgnition coils, Vehicle speed sensor, VTEC solenoid valve
BRNA/EL: Camshaft oosition (CMP) sensor. CKP sensor, TDC sensor. VTEC oil pressure switch
G 15']EPS control unit
G201ELD unit. Multiplex control inspection connector, Multiplex control unit, Power window relay, Rear
window washer motor, Right front parking light, Right front side marker light, Right front turn signal
light, Turn signal/hazard relay, Washer fluid level sensor (Canada) , Windshield washer motor,
Windshield wiDer motor
G202ABS modulator-control unit
G301
G401
Blower motor relay, Brake fluid level switch, Condensor fan motor, Cruise control actuator, Left front
parking light, Left front side marker light, Left front turn signal light, Radiator fan motor, Radiator fan
swrtcn
Combination liqht switch, lqnitlon kev srvitch, Wiper/wasfrer sr,virch
G402Left and riqht airbaq sensors, SRS unit
G 451Data link connector (DLC)
G501Clutch interlock switchm Clutch pedal position switch (for cruise control), Cruise control main switch,
Cruise control unit, Daytime running lights control unit (Canada), Driver's door lock knob switch,
Driver's door lock switch, Driver's power window motor, Heater control panel, Left power mirror
defogger (Canada), left side turn signal light, Moonroof control unit, Monroof open and close relays,
Moonroof position sensor '1, Moonroof seitch, Power mirror switch, Power transistor, Power window
master switch. SDotliqhts
G502Accessory power socket, Gauge assembly, Keyless receiver unit, lvlultiplex control unit, Right power
mirror defogger {Canada)
G503Audio unit
G551Driver's seat belt switch, Fuel gauge sending unit, Fuel pump, Memory erase signal (IMES) connector,
OPDS unit. Rioht seat belt switch
G552High mount brake light, License plate lights, Rear window defogger, Rear window defogger noise
condenser. Rear window wioer motor, Hatch latch switch
Back-up lights, Brake lights, Rear side marker lights, Rear turn signal lights, Rear window wiper noise
condenser, Rear window wiper intermittent control unit, Taillights
22-48

Gauges
\-Component Location Index
PARKING BRAKE SWITCHpage 19-10
FUEL GAUGE SENDINGpage 11-156ENGINE OIL PRESSURE SWITCHpage 8-4
GAUGE ASSEMBLYSelJ-diaqnostic Procedure, page 22-56Gauqe dulb Replacement, page 22 63Rep6cement, page 22-64Coolant Temperature GaugeTroLrbleshooting, page 22'64
BRAKE FLUID LEVEL SWITCHpage 19-10VEHICLE SPEED SENSOR {VSS)Troubleshooting, page 22-65Beplacement, page 22-67
22-54
\

Gauges
Self-diagnostic Procedure
The gauge assembly has a self-diagnosis function.. The Beeper Drive Circuit Check. The Indicator Drive Circuit ChecL. The LCD Segments Check. The Gauges Drive Circuit Check (Speedometer, Tachometer, Fuel gauge, Coolant temperature gauge). The Communication Line Check (the coolanttemperature signal line between the gauge and ECM)
NOTE: Indicators are also controlled via the communication line.
Entering the self-diagnosis f unction:
Before doing the self-diagnosis function, check the No. 9 (10A) fuse in the under-hood fuse/relay box and No. 10 {7.5A)fuse in the under'dash fuse/relay box.
1. Push and hold the trip/reset button.
2. Turn the lighting switch ON.
3. Turn the ignition switch ON (ll).
4. Within 5 sec., turn the lighting switch OFF, then ON and OFF again.5. Within 5 sec., release the trip/reset button, then push and release the button four times reDeatedlv.
NOTE:. While in the self-diagnosis mode, the dash lights brightness controller operates normally.'Whileintheself-diagnosismode,thetrip/resetbuttonisusedtostartthebeeperdrivecircuitcheckandthegauge
drive cicuit check.. lf the vehicle speed exceeds 1.2 mph 12 km/h) orthe ignition switch is tu rned OFF, the self,diag nosis mode ends.
oN flrl
lgnition
Switch
Lighting
Switch
Trip/Reset
Switch-> Move to selt-diagnosis mode.
5 sec.5 sec.
The Beeper Drive Circuit Check:
When entering the self-diagnosis mode, the beeper sounds five times
The Indicator Drive Circuit Check:
When entering the self-diagnosis mode, the following indicators blink.
Seat belt indicator, Door/hatch indicator, Brake system, Lowfuel indicator, Maintenance required indicator (USA),
Washer fluid level indicator (Canada), Oil pressure light.
v
OFF
22-56

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)

)
Orive BehInspecaron................ 4-26
Door PanelsRemoval/lnstallation -............................. 20-4
Door Sash TrimRep1acement......................................... 20 10
Door StrikersAdiustment ........................................... 20-13
Door Weatherst psBeplacement...........-............................. 20 1 1
EPS Conirol UnitRemoval/1nsta11ation ..................-......... 17-67
EPS Indicator CircuitTroubleshooting ................................... 17 -47
EPS MotorRemoval/lnstallation .-.......................... 17-49
EVAP CanisterRep1acement......................... ......... 11,189
EVAP Control Syst€mComponentLocation Index ..............'11-170
EVAP Two-Wey ValveTest ..........-.............-............................ 11 186
Evaporetor CoreRep1acement........................ . ... 21-42
Evaporator Tomperature SensorReplacement......................................... 21 -37Test..................................... ..........2137
EvaporrtoFHeater UnitReplacement........................................ 21 43
Exhaust ManifoldRemoval/1nsta11ation ................................ I 7
Exhaust Pipe8ep|acement............................................. 9-8
Front SpeakersRep|acement....................................... 22-102
Front SuspensionComponentLocation Index................... 18-3
Fueland EmissionsDescription ........................................... 11-12
Fuel Fill DoorAdjustment ..........-................................ 20 93
Fuel Fill Door OpenetBeplacement........................ . ............ 20.109
Fuel Fill Door Opener CableReplacement....................................... 20- lO7
Fuel FilterReplacement....................................... 1 1-152
Fuel Gauge Sending UnitTest ......................-.-..........-.................. 11'156
Fuel Injection Syslem (PGM"FIlComponent Location 1ndex................. 11-49
Fuel IniectorsRep1acemen1....................................... 1 1 1 1 l
Fuel Lines and HosesInspection .......................................... 1 1'146Removal ....................... . .. . .... 11-149Insta|1ation .......................................... 1 1 150
FuelPipe ProtectolReplacement....................................... 20-104
Fuel Pressure RegulatotReplacement....................................... 1 1-152
Fuel Pulsation DamperReplacemenl................................... 11 154
Fuel PumpReplacement,,,,,.,.,.,,,.,,,,,,,,,,,,.,.,.,,,..,.. 11-153
Fuel Pump CircuitTroubleshooting -.......-....................... 1 1-141
FuelSupply SystemComponent Location lndex .............. 11 140Adjustment................................... 11-144Test........-...-................. ... ............- 11-145
FuelTankBeplacemenl.............. . ..... .. 11 155
Fuel Tank Vapor ControlValveTest ......................-....... ... . . 11-187Replacement,,.,,...,.,,,.,.,,,,... .. .. 11 189
Fuses{See first page ofthis Index)
)
Rep|acement................. ..................... 4 26
Drive Belt Auto-tensionellnspection ............................................... 4 21Rep1acement.................................... ..4-28
Driver's PocketRemoval/lnstallation -........................... 20-60
Driver's TrayRemoval/lnstallation .........................-.- 20-65
DRL {Daytime Running LightslControl Unitlnput Test .................... ........ . . . ......22-16
DTCs(See first page olthis Index)
Dust and Pollen FillerReplacement......................................... 21-39
Dynamic Damper, DriveshaftsReplacement........................................... 16-8
ECT SensorReplacement.,.,,,.,.,,,,,,,,,,,,,,................ 1 1-1 14
El€ctrical Power Steering IEPS)Signal CircuitTroubleshooting ........ ... .. 11-135
EmblemsReplacement......................-................ 20-100
Engine AssemblyRemova1 .................................................... 5 2Installation ............._.................................. 5-9
Engine Block AssemblyComponent Location Inder ..................... 7.3
Engine Block, BareInspect|onRepair
Fan ControlsComponent Location Index................. 10'l 1Circuit Diagram .. ..... . .. . .................. 10 13
Fender Fairing, FrontReplacement...-................................... 20-103
Final Driven Gear. M/TReplacement.... . . ................................ 13-53
FrameRepair Chan............ ... ....................... 20 11 4
Frame StiffenelReplacement......-................................ 20- J'13
Front ConsoleRemoval/lnstallation ............................ 20 5lDisassembJy/Reassemb|y ................... 20 58
Front DoorsComponent Location Index................... 20-2Adiustment ........................................... 20.12
Front Driveshaft AssemblyInspeclion .................... ... ....16 3Remova1...................-...... ... .....16-3Disassembly ............................... .....165Resassemb|y ................................-......... 16-9Insta11arion ........................ ...... ............ l6 17
Front lmpact SensorsRep1acement............................ ...23 125
................7-15................1 11
)
Entry Light Control SystemComponent Location Index ...............-. 22-89Circuit Dia9ram .................................... 22 90
EPS ComponentsComponent Location 1ndex..........-...... 17-!7Description ........................ ...... ..17-24Circuit Diagram11 26(cont'd)