2003 HONDA CIVIC Workshop Manual

ldle Control System
ldle Speed lnspection
NOTE:' Leave the idle air control (lAC) valve connecled.. Before checking the idle speed, check these items:- The malfunction indicator lamp (MlL) has not been
reported on.- lgnition timing- Spark plugs- Air cleaner- PCV system. Pullthe parking brake lever up. Start the engine, and
make sure the headlights are off.
1. Disconnect the evaporative emission (EVAP)
canister purge valve 2P connector.
2. Connect a tachometer (A)to the test tachometer
connector (B), or connect the Honda PGM Tester (C)
or an OBD ll scan tool to the data link connector(DLC) (D) located under the driver's side of the
dashboard.
11-138
4.
3.
5.
6.
Start the engine. Hold the engine at 3,000 rpm with
no load (in neutral) until the radiator fan comes on,
then let it idle.
Check the idle speed with no-load conditions;
headlights, blower fan, radiator fan, and air
conditioner off.
ldle speed should be: 750 t 50 rpm
Let the engine idle for 1 minute with the heater fan
switch on Hl and air conditioner on, then check the
idle speed.
ldle speed should be: 750 t 50 rpm
NOTE: lf the idle speed is not wilhin specification,
go to the Symptom Troubleshooting Index,
Reconnect the EVAP canister purge valve 2P
connector.

ECM ldle Learn Procedure
The idle learn procedure must be done so the ECM can
learn the engine idle characteristics.
Do the idle learn procedure whenever you do any of
these actions:. Disconnect the battery.
Replace the ECM or disconnect its connector.
Reset the ECM.
NOTE: Erasing DTCS with the Honda PGM Tester
does not require you to do the idle learn procedure.
Remove the No.6 ECU {ECM) ( 15A) fuse from the
under-hood fuse/relay box.
Remove the No.19 baftery (80A) fuse from the under-
hood fuse/relay box.
Remove PGM-FI main relay 1.
Remove any of the wires from the under-hood fuse/
retay Dox.
Disconnect any of the connectors from the under
hood fuse/relay box.
Disconnect the connector between the engine
compartment wire harness and ECM wire harness.
Disconnect the G2 terminal from the transmission
ho u srng.
Disconnectthe G'l terminal from the body.
Disconnectthe G101 terminal from the cylinder head
cover.
Procedure:
To complete the idle learn procedure, do this:
1. Make sure all electrical items (Ay'C, audio, rear
defogger, l:ghts, etc.,) are off.
2. Start the engine, and hold it at 3,000 rpm with no
load {in neutral) until the radiator fan comes on, or
until the engine coolanttemperature reaches 194"F(90'c).
3. Let the engine idle for about 5 minutes with the
throttle fully closed.
NOTE: lf the radiator fan comes on, do not include its
running time in the 5 minutes.
11-139

Fuel Supply System
{
a
Component Location Index
FUEL FEED LINEFUEL PULSATION DAMPERReplacement, page 1 1'154
PGM.FI MAIN RELAY 2Troubleshooting, page'l'l-141
FUEL TUBE/OUICK.CONNECT FITTINGSPrecautions, page 1 1-148Removal, page 11-'149Installation, page 1 1-'l50
FUEL VAPOR LINE
i../
PUMPTest, page 11-141
FUEL FILL CAP
FUEL TANKReplacement, page'l 1-155
PGM.FI MAIN RELAY 1
Fleplacement, page 1 1'1 53FUEL FILTERReplacement, page 1 1-1 52FUEL GAUGE SENDING UNITTest, page 11-156Replacement, page 1 1-153FUEL PRESSUN REGULATORReplacement, page'1 1-'152
11-140

Fuel Pump Circuit Troubleshooting
lf you suspect a problem with the fuel pump, check that
the fuel pump actually runs; when it is on, you will hear
some noise if you listen to the fuel fill port with the fuel
fill cap removed. The fuel pump should run for 2
seconds when the ignition switch is first turned on. lf
the fuel pump does not make noise, check as follows:
1. Turn the ignition switch OFF.
2. Remove the glove box {see page 20-63), then
remove the PGM-FI main relay 2 (A).
Turn the ignition switch ON {ll).
Measure voltage between PGM-Fl main relay 2 5P
connector lerminal No. 5 and body ground.
PGM.FI MAIN RELAY 25P CONNECTOR
IGPl(YEL/BLK}
Wire side of female terminals
ls there battery voltage?
YES-Go to step 5.
NO Repair open in the wire between the PGM'Fl
main relay 1 and the PGM-Fl main relay 2.t
3.
5. N4easure voltage between PGM-Fl main relay 2 5P
connector terminal No. 1 and body ground.
PGM.FI MAIN RELAY 25P CONNECTOR
Wire side oJ female terminals
ls there battery voltage?
YES Go to step 6.
NO Repair open in the wire between the under-
dash fuse/relay box and PGM-Fl main relay 2.1
6. Turn the ignition switch OFF.
7. Disconnect ECM connector E (31P).
8. Check for continuity between PGM-FI mainrelay2
5P connector terminal No. 3 and ECM connector
terminal E1.
PGM-FI MAIN RELAY 2 5P CONNECTOB
Wire side of female terminals
ls there continuity?
YES-Go to step 9.
NO-Repair open in the wire between the PGM Fl
main relay 2 and the ECM (E1).1
IMOFPR(GBN/YEL)
(cont'd)
11-141
Et2lFtxm
7-
z
ECM CONNECTOR E 131P}

FuelSupply System
(
(
L
10.
1'].
Fuel Pump Circuit Troubleshooting (cont'dl
Reinstallthe PGM-Fl main relay 2.
Turn the ignition switch ON (ll).
Measure voltage between ECI\4/PCM connector
terminal E1 and body ground.
ECM CONNECTOB E {31P)
ls there battety voltage?
YES Go to step 12.
NO-Replace the PGM-Fl main relay 2.1
Turn the ignition switch OFF.
Reconnecl ECM connector E (31P).
Turn the ignition switch ON (ll), and measure
voltage between ECM connector terminal E1 and
body ground within the first 2 seconds after the
ignition switch was turned ON (ll).
ECM CONNECTOR E (31PI
13.
14.
Wire side of female terminals
Wire side of female terminals
11-142
t5.
to.
11.
18.
ls there battery voltage?
YES U pdate the ECM if it does not have the latest
so{1ware, 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 ECM.I
NO Go to step 15.
Turn the ignition switch OFF.
Remove the rear seat cushion (see page 20-80).
Remove the access panel from the floor.
Measure voltage between fuel pump 5P connector
terminal No. 5 and body ground within the first 2
seconds after the ignition switch was turned ON (ll).
FUEL PUMP 5P CONNECTOR
wire side oI female terminals
ls there battery voltage?
YES Go to step 24.
NO-Go to step 19.
Turn the ignition switch OFF.
Remove the PGM-Fl main relay 2.
19.
20.

21. Connect PGM-Fl main relay 2 5P connector
terminals No. 1 and No. 2 with a iumDer wire.
PGM.FI MAIN RELAY 25P CONNECTOR
FUELPUMP(YEL/GRN)JUMPERWIRE
22.
23.
Wire side of {emale terminals
Turn the ignition switch ON (ll).
Measure voltage between fuel pump 5P connector
terminal No. 5 and body ground.
FUEL PUMP 5P CONNECTOR
Wire side ol female terminals
ls there battery voltage?
YES Replacethe PGM-Fl main relay2.t
NO-Repair open in the wire between the PGM-Fl
main relay 2 and the fuel pump 5P connector.l
Turn the ignition switch OFF.24.
FNI E
tri dffircr fv{YEL/BLK)
A
25. Check for continuity between fuel pump 5P
connector terminal No. 4 and body ground.
FUEL PUMP 5P CONNECTOR
Wire side of female terminals
ls there continuity?
YES Replace the fuel pump.l
NO-Repair open in the wire between the fuel
pump 5P connector and G551.1
11-143

FuelSupply System
Fuel Pressure Relieving
Before disconnecting fuel lines or hoses, relieve
pressure from the system by disconnecting the fuel
tube/quick connect fitting in the engine compartment.
1. Turn the ignition switch OFF,
2. Remove the PGM-Fl main relay 2 (A).
Startthe engine, and let it idle until it is stalls.
NOTE: The DTCS or Temporary DTCS P0301. P0302,
P0303, P0304 may come on during this procedure.
lf any DTCS are stored, ignore them.
Turn the ignition switch OFF.
Remove the fuel fill cap, and relieve fuel pressure
in the fueltank.
Remove the engine cover.
Disconnect the negative cable from the battery.
Check the fuel quick-connect fitting for dirt, and
clean it if necessary.
3.
4.
6.
7.
8.
11-144
11
10.
9. Place a rag or shop towel over the quick-connect
fitting (A).
Disconnect the quick-connect fifting (A): Hold the
connector (B) with one hand and squeeze the
retainer tabs (C) with the other hand to release
them from the locking pawls {D). Pullthe connector
off.
NOTE:. Prevent the remaining fuel in the fuel feedlineor
hose from flowing out with a rag or shop towel.. Be careful notto damage the line (E) or other
pa rts.. Do not use tools.. lf theconnectordoes not move, keepthe retainer
tabs pressed down, and alternately pull and push
the connector until it comes off easily.. Do not remove the retainer from the line; once
removed, the retainer must be replaced with a
new one.
After disconnecting the quick-connect fifting, check
it for dirt or damage (see page 1 1-149).

Fuel Pressure Test
Special Tools Required. Fuel pressure gauge 07406-0040004. Fuel pressure gauge sel 07ZAJ-S5A0100
1. Relieve the fuel pressure (see page 1'1-144).
2. Disconnect the quick-connect fitting (A). Aftach the
fuel pressure gauge set and fuel pressure gauge.
Start the engine and let it idle.
. lf the engine starts, goto step 5.. lf the engine does not start, goto step 4.
Check to see if the fuel pump is running: listen to
the fuel fill port with the fuel fill cap removed. The
fuel pump should run for 2 seconds when the
ignition switch is first turned on.
. lf the pump runs, go to step 5.. lf the pump does not run, do the fuel pump circuit
troubleshooting (see page 1 1-1 41 ).
Read the pressure gauge. The pressure should be
320-370 kpa (3.3-3.8 kgf/cm', a7-52 psi)
. lf the pressure is OK, the test is complete.. lf the pressure is out of specification, replace the
fuel pressure regulator and the fuel filter (see
page 11-152), then recheck the fuel pressure.
5.
11-145