2003 HONDA CIVIC Front

ECM Inputs and Outputs at Connector A (31P)
NOTE: Standard battery voltage is 12 V.
1AFS]TC2
]GP23IGPl^:^ I -:,6AFS+1
CKPIKS
'10
SG2t112ACV15TPST6AFS_18
VSS
19IVAP2Avcc221vccl
22
HTC+
23LG225CMPA
26CMPB(rDc)
27tGPts,l28rcPts329tGPts230GPLS 1
Wire side ol female terminals
Terminalnumb€rWho colorforminal nameDescriptionSignal
ELKAVHTAFSHTC (AIR FUEL RATIO(4./F)SENSOR HEATERCONTROL}
Drives Ay'F sensor heaterWith ignit'on switch ON {ll): battery voltageWith fully warmed up engine runnang: 0 V
2YEUBLKIGP2 (POWEB SOURCE)Power source for the ECMcircuitWith the ignition switch ON 1ll): battery voltageWith the ionition switch OFF: about 0 V3YEUBLKIGPl {POWER SOURCE)Power source for the ECMWith the ignition swatch ON {ll): battery voltageWith the ionition switch OFF: about 0 V4BLKPG2 (POWER GROUNDGround forthe ECM circuitLess than 1.0 V at all times5BLKPG1 (POWER GROUNDGround forthe ECM circuitLess than 1.0 V at all times6REDAFS + (AIR FUEL RATIO(A,/F}SENSOR, SENSOR 1+ stDE)
Detects Ay'F sensor{sensor 1) signal
18LUCKP (CRANKSHAFTPOSITION SENSOR)Detects CKP sensor signalWith engine running: pulses
9BED/BLU)K SENSOB)Detects knock sensor siqnalWith enqine knocking: pulses10YEL2 {SENSOR;ROUND);ROUND)Sensor qrounrLessthan 1.0V at elltimesG1 {SENSORSensor qroun(Lessthan 1.0V at alltimes12BLIVREDIACV (IDLE AIR CONTROL(IAC)VALVE)Drives IAC valveWith engine runningr duty controlled
RED/BLKTPS (THROTTLE POSITIONSENSOR)Detects TP sensor signalWith throttle fully open: about 4.8 VWith thronle fullv closed: ahout 0-5 VREDI/ELAFS (AIR FUEL RATIO(4,/F)SENSOR, SENSOB 1SIDE)
Detects !y'F sensor(sensor 1)signal
18WHT/GRNVSS (VEHICLE SPEEDSENSOR)Detects VSS signalWath ignition switch ON (lli and front wheelsrotating: cycles from about 0 V to about 5 V or
(cont'd)
11-19

Fuel and Emissions Systems
System Descriptions (cont'dl
Vacuum Hose Routing
!
INTAKE AIRBYPASS CONTROLTHERMAL VALVE
\*
FRONT OFVEHICLE
EVAPORATIVE EMISSION{EVAP} CANISTER PURGE VALVE
11-24
\,

Fuel and Emissions Systems
System Descriptions (cont'dl
Gatalytic Converter System
Three Way Catalytic Converter (TWC)
The TWC converts hydrocarbons (HC), carbon
monoxide {CO), and oxides of nitrogen (NOx) in the
exhaust gas to carbon dioxide (C02), dinitrogen (N2),
and water vaDor.
THREE WAYCATALYST
FRONT OFVEHICLE
11-34
Positive Crankcase Ventilation (PCVI System
The PCV valve prevents blow-by gasses from escaping
into the atmosphere by venting them into the intake
manifo ld.
:: BLOW-BY VAPOR€: FRESH AIR
\
BREATHER PIPE
{

PGM-Fl System
6.
1.
DTC Troubleshooting (cont'dl
DTC P0500: VSS Circuit Malfunction
1. Test-drive the vehicle.
2. Check the vehicle speed with the scan tool.
ls the correct speed indicated?
YES-lntermiftent failure, system is OK at this time.
Check for poor connections or loose terminals at
the VSS and at the ECM.I
NO Go to step 3.
3. Turn the ignition switch OFF.
4. Block the rear wheels, and set the parking brake.
5. Raise the front ofthe vehicle, and make sure it is
securely supported,
Turn the ignition switch ON (ll).
Block the right front wheel, and slowly rotate the
left front wheel.
8. Measure voltage between ECM connector
terminals A18 and A24.
ECM CONNECTOR A {31P)
Wire side of female terminals
Does the voltage pulse between 0 V and 5 V or
between 0V and battery voltage?
YES-Update the ECM if it does not have the latest
software, or substitute a known-good ECM. then
recheck (see page 1 1-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECN4.l
NO Go to step 9.
11-80
9. Turn the ignition switch OFF.
10. Disconnect ECM connector A (3'1P).
1 1. Turn the ignition switch ON {ll}.
12. Blockthe right front wheel. and slowly rotate the
left front wheel.
'!3. lMeasure voltage between ECM connector
terminals A18 and A24.
ECM CONNECTOR A I31PI
Wire side of female terminals
Does the voltage pulse between 0 V and 5 V ol
between 0V and battety voltage?
YES Update the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 1 1-6). lf the symptom/indication
goes away with a known-good ECM, replace the
origlnal ECM.I
NO Check these items:
. A short or an open in the wire between the ECM
(A18) and the VSS.I. lf thewire is OK,testtheVSS (see page 22 71).1

Manual Transmission
Transmission Removal (cont'd)
15. Remove the transmission mount bracket (A) and
transmission mounting bolt (B).
Remove the air cleaner bracket {C).
Raise the vehicle, and make sure it is securely
supponed.
Drain the transmission fluid. Reinstall the drain bolt
with a new washer (see page 13-3).
Remove the splash shield.
€Ds
to.
17.
18.
19.
db--qF
13-6
20.
21.
22.
23.
Remove the three way catalytic converter (TWC)
assembly (see step 30 on page 5-5)
Remove the driveshafts (see page 16-3).
Remove the intermediate shaft {see page 16-19).
Remove the front engine mount bracket mounting
bolt.
Remove the three bolts securing the transmission
rear mounI.
24.

25. Support the subframe with the subframe adapter
and a jack.
---
26.
EOS02C000011
Make reference marks (A) on the front suspension
subframe (B) and mounting bolts (C). then remove
the front suspension subframe.
27. Remove the clutch cover.
28. Remove the front engine mount.
Place the transmission iack under the transmission,
and remove the transmission mounting bolts.
29.
(cont'd)
13-7

5. Install the transmission mounting
12 x 1.25 mm64 N.m 16.5 kgf m.47 lbt ft)
12 x 1.25 mm64 N.m (6.5 kgf.m,47 lbf.ft)
6. Installthe front engine mount.
12 x 1.25 ftrn64 N.m(6.5 kgf m. 47 lbf.ft)
bolts.
12x 1.25 mm64 N.m(6.5 kst.m,47 lbf ft)
7. lnstallthe clutch cover.
6x1.0mm12 N.m {1.2 kgI.m, 9 lbf ftl
8. Supportthe subframe with the subframe adapter
and a jack.
Installthe front suspension subframe (A) in its
original position by aligning the marks (B) you
made in the removal procedure,
9.
14 x 1.5 mm
(cont'd)
13-9

Manual Transmission
Transmission Installation (cont'dl
'10. Installthe three rear mounting bolls for the
transmission rear mount.
59 N.m (6.0 kgf.m,43 tbf.ft)
Loosely tighten the front engine mount bracket
mounting bolt.
11.
12.
t5.
14.
Install the intermediate shaft (see page 16-24).
Installthe drivershafts (see page 16-17).
lnstall the three way catalytic converter (TWC)
assembly (see step 17 on page 5-12).
10 x 1.25 mm
13-10
6x1.0mm12Nm
15.Install the transmission mount bracket (A) and the
transmission mounting bolt {B).
12 x 1.25 mm54 N.m {5.5 ksf.m, 40lbf.ft)
12x 1.25 nn54 N.m(5.5 kgf.m,40 tbt.ft)
16.
17.
/t':::= 12 x 1.25 mm-) 54 N.m(5.5 kgf.m,40 tbf.ftl
Install the air cleaner bracket (C).
Install the two upper transmission mounting bolts.
12 x 1.25 mrn64 N.m (6.5 kgt.m,47 lbf.ftl
18. Remove the engine hanger and special tool from
engrne.