2003 HONDA CIVIC ecm

Engine Assembly
Engine Removal (cont'dl
14. Remove the clutch slave cylinder {A) andclutchline
bracket mounting bolt (B).
15. Remove the shift cable (A) and select cable (B).
5-4
..4,
16. Disconnect the engine control module (ECM)
connectors (A) and main wire harness connector(B).
Remove the harness clamps (A) and grommet (B),
then pullthe engine wire harness through the
bulkhead.
't7 .
\l,

27. lnstallthe upper radiator hose {A) and heater hoses(B).
Push the engine control module (ECM) connectors
through the bulkhead, then installthe grommet (A).
29. Installthe harness clamps (B).
30. Connect the ECI\4 connectors (A) and main wire
harness connector (B).
Install the throttle cable (see page 11-164), then
adjustthe cable {see page 11-'163).
Installthe cruise control cable (see page 4-44), then
adjust the cable (see page 4-45),
Install the brake booster vacuum hose (A) and the
evaporative emission (EVAP) canister hose (B).
34. Installthe fuel line (see page 11-150).
31.
32.
33.
(cont'd)
5-13

40. Install the air cleaner housinq.
6x1.0mm12 N m (1.2 kgf.m,8.7 lbt.ft)
Install the air cleaner housing cover (A) and
connect the intake air temperature (lAT) sensor
connector (B),
42. Installthe breather hose (C) and vacuum hose 1D).
41.
43. Installthe intake manifold cover.
6x1.0mm12Nm11.2kgf.m.8.7 tbf.ft)
Installthe battery. Clean the battery posts and
cable terminals with sandpaper, then assemble
them and apply grease to prevent corrosion.
Check that the transmission shifts into gear
smoothly.
Inspect for fuel leaks. Turn the ignition switch ON(ll) {do not operate the starter) so that the fuel pump
runs for about 2 seconds and pressurizes the fuel
line. Repeat this operation two or three times, then
check for fuel leakage at any point in the fuel line.
Refillthe engine with engine oil (see page 8-5).
Refill the transmission with fluid (see page 13-3).
Refill the radiator with engine coolant, and bleed
air from the cooling system with the heater valve
open (see page 10-6).
Perform the engine control module (ECM) idle learnprocedure (see page 11-139).
Inspect the idle speed (see page 1 1-138).
Inspect the ignition timing (see page 4-17).
Check the wheel alignment {see page 18-4).
Enter the anti-theft code for the radio, then enter
the customer's radio station presets.
Set the clock.
YE
44.
41.
]tE
46.
48.
49.
52.
53.
54.
50.
51.
55.
5-15

Fan Controls
Radiator Fan Switch Circuit
Troubleshooting (Openl
1. Disconnect the radiator fan switch 2P connector.
2. Turn the ignition switch ON (ll).
3. Measure voltage between the No.2 terminal ofthe
radiator fan switch 2P connector and body ground.
RADIATOR FAN SWITCH 2PCONNECTOR
ls there battety voltage?
YES-Go to step 4.
NO- Repair open in the wire between the radiator
fan switch 2P connector terminal No. 2 and under-
hood fuse/relay box.l
Turn the ignition switch OFF, and check for
continuity between the No. '1 terminal of the
radiator fan switch 2P connector and body ground.
RADIATOB FAN SWITCX 2PCONNECTOR
ls there continuity?
YES Replace the radiator fan switch. t
NO Check for an open in the wire between theradiator fan switch 2P connector terminal No. 1 and
body ground. lf the wire is OK, check for a poor
ground at G301.1
10-16
\-
Radiator Fan Switch Circuit
Troubleshooting (Short)
NOTE: After troubleshooting, perform the engine
control module (ECM)idle learn procedure (see page
1 1,139).
1. Remove the radiator fan relay from the under-hood
fuse/relay box, and test it (see page 22-51).
ls the relay OK?
YES Go to step 2.
NO Replace the radiator fan relay.I
2. Remove the radiator fan switch, and test it (see
page 10-17 ).
Is the radiatot tan switch OK?
4.
YES Go to step 3.
NO Replace the radiator fan switch.I
Disconnect the battery negative cable from the
battery.
Disconnect engine control module {ECM) connector
B (24P) and the under hood fuse relay box 14P
connector.
Check for continuity between the No. 2 terminal of
the radiator fan switch 2P connector and bodygrouno.
RADIATOR FAN SWITCH2P CONNECTOR
lstnere continuity?
YES Repair short in the wire between the radiator
fan switch 2P connector terminal No. 2 and under-
hood fuse/relay box.l
NO Replace the under-hood fuse/relay box.t
\I
\

Fuel and Emissions
Fuel and Emissions Systems
SpecialTools
General Troubleshooting
Information
DTC Troubleshooting lndex ....
Symptom Troubleshooting
1ndex...............
System Descriptions ................
Howto Set Readiness Codes ..
PGM-FlSystem
Component Location Index ....
DTC Troubleshooting ..............
MIL Circuit Troubleshooting ...
DLC Circuit Troubleshooting ..
Injector Replacement ...............
A,/F Sensor Replacement .........
Secondary HO2S
Replacement
ECT Sensor Reolacement .......
CMP Sensor B {TDC Sensor)
Replacement
IAT Sensor Replacement .........
Knock Sensor Replacement ....
CKP Sensor Reolacement .......
VTEC/VTC
Comoonent Location Index ....
DTC Troubleshooting ..............
VTC Oil Control Solenoid
Valve Removal/Test .............
CMP Sensor A Replacement ...
VTEC Solenoid Valve
Removal/lnsoection .............
ldle Control System
Component Location Index
DTC Troubleshooting ..............
A,/C Signal Circuit
TroubleshootinS ...................
Alternator FR Signal Circu it
TroubleshootinS ...................
EPS Signal Circuit
TroubleshootinS ...................
Brake Pedal Position Switch Signal
Circuit Troubleshooting .............
ldle Speed Inspection
ECM ldle learn Procedure .......
Fuel Supply System
Component Location Index
Fuel Pump Circuit Troubleshooting
1't-2
I I-J
11-7
1 1-10
11-12
11-46
11-49
11-52
11-97
11-109
11-111
11-113
11-113
11-114
11-114
11-115
11-115
11-116
11-117
1 1-1 18
11-127
11-128
11-128
11-129
1I-130
I t- t55
11-134
1 1- 135
1 1-137
1 1-138
1 1-139
1 1-140
11-141
11-144
Fuel PressureTest ................... 11-145
Fuel Lines Inspection ............... 11-146
Fuel Line/Ouick-Connect
Fittings Precautions ............. 1 1-148
Fuel Line/Ou ick-Con nect
Fittings Removal .................. 1 1-149
Fuel Line/Ou ick-Con nect
Fittings lnstallation ............... 11-150
Fuel Pressure Regu lator
Replacement ......................... 11-152
Fuel Fifter Replacement ........... 11-152
Fuel Pump/Fuel Gauge Sending
UnitReDlacement ................. 11-153
Fuel Pulsation Damoer
Rep1acement ......................... 11-154
Fuel Tank Reolacement ........... 11-155
Fuel GaugeSending UnitTest ....... 11-156
Low Fuel lndicatorTest ................. 1 1-158
Intake Air System
Comoonent Location Index .... 11-159
Throttle BodyTest ................... 11-160
Intake Air Bypass Control
Thermal Valve Test .............. 11-161
Air Cleaner Reolacement ........ 11-162
Air Cleaner Element
Reolacement ......................... 11-162
Throttle Cable Adjustment ...... 11-163
Th rottle Cable
Removal/lnstallation ............ 1 1-164
Th rottle Body Removal/
Installation .. 11-165
Th rottle Body Disassembly/
Reassemblv .......................... 11-166
Catalytic Converter System
DTC Troubleshooting .............. 1 1-167
PCV System
DTC Troubleshooting .............. 1 1-168
PCV Valve InsDection
and Test ...... 1 1- 169
PCV Valve Reolacement .......... 11-169
EVAP System
Component Location Index .... 11-170
DTCTroubleshooting .............. 11-171
EVAP Two Way Valve Test ...... 11-186
Fuel Tank Vaoor Control
Valve Test ... 11-187
EVAP Canister Replacement ... 11-189
Fuel Tank Vaoor Control
Valve Reolacement .............. 1 1-189Fuel Pressu re Relieving ...........

General Troubleshooting Information
Intermittent Failures
The term "intermittent failure" means a svstem mav
have had a failure. but it checks OK now. lf the
Malfunction Indicator Lamp (MlL) on the dash does not
come on, check for Door connections or loose terminals
at all connectors related to the circuit that Vou are
troubleshooting.
Opens and Shorts
"Ooen" and "Short" are common electrical terms. An
open is a break in a wire or at a connection. A short is
an accidental connection of a wire to ground or to
another wire. In simple electronics, this usually means
something won't work at all. With complex electronics(such as ECMs)this can sometimes mean something
works, but not the way it's supposed to.
How to Use the PGM Tester or a Scan Tool
lf the MIL {Malfunction Indicator Lamp} has come on
'1. Start the engine and check the MIL {A).
NOTE: lf the ignition switch is turned ON (ll), and
the engine is not started, the MIL will stay on for
15 20 seconds (see page 11-46).
K-> ;"PN/.- -::: - -d V-: !
w:ix&K#
2. lf the MIL stays on, connect the Honda PGM Tester(A) or an OBD ll scan tool to the Data Link
Connector {DLC) (B) located under the driver's side
of the dashboard.
3.
5.
Turn the ignition switch ON (ll).
Check the Diagnostic Trouble Code (DTC) and note
it. Also check the freeze data. Refer to the DTC
Troubleshooting Index, and begin the appropriate
troubleshooting procedure.
lf you do not find any DTCS, go to MIL circuit
troubleshooting (see page 11-97).
NOTE:. Freeze data indicates the engine conditions when the
first malfunction, misfire, or fuel trim malfunction
was detected.. The scan tool and the Honda PGM Tester can read the
DTC, freeze data, current data, and other Engine
Control l\4odule {EClvl) data.. For specific operations, refer to the user's manual
that came with the scan tool or Honda PG l\4 Tester.
lf the MIL did not stay
lf the MIL did not come on but there is a driveability
problem, refer to the Symptom Troubleshooting Index
in this section.
lf you can't duplicate the DTC
Some of the troubleshooting in this section requires
you to reset the ECM and try to duplicate the DTC. lf rhe
problem is intermittent and you can't duplicate the code,
do not continue through the procedure. To do so will
only result in confusion and, possibly, a needlessly
replaced ECM.
(cont'd)
11-3

Fuel and Emissions Systems
General Troubleshooting Information (cont'dl
How to Reset the ECM
You can reset the ECM in either of two ways:
. Use the OBD ll scantool or Honda PGMTesterto
reset the ECM memory.
See the OBD ll scan tool or Honda PGI\4 Tester user's
manuals for specific instructions.' Turn the ignition switch OFF, and remove the No. 6
ECU {ECM} (15A) fuse (A)from the under-hood fuse/
relav box (Blfor 10 seconds.
How to End a Troubleshooting Session
(required after any troubleshootingl
1. Reset the ECM as described above.
2. Do the ECM idle learn procedure (see page 11-139)
3. Turn the ignition switch OFF.
4. Disconnectthe OBD ll scan tool or Honda PGM
Tester from the DLC.
NOTE: The ECM is part of the immobilizer system.
lf vou replace the ECM, it will have a different
immobilizer code. In order for the engine to start,
you must rewrite the immobilizer code with the
Honda PGM Tester.
11-4
\- ta
J
How to Remove the ECM for Testing
1. Remove the passenger's dashboard lower cover
{see page 20-63), the passenger's kick panel (see
page 20-63), and the glove box (see page 20-63).
2. Remove the ECM mounting bolts (B) and the ECM
(c),
9.8 N.m{1.0 kgf.m,7.2lbt.ft}
3. Remove the ECM (B).
4. Installthe ECM in the reverse order of removal.
L

How to Troubleshoot Circuits at the ECM
Special Tools Required. Digital Multimeter KS-AHM-32-003 (1) or a
commercially available digital multimeter. Backprobe Set 07SAZ-0010004 (2)
1. Connect the backprobe adapters (A) to the stacking
patch cords (B), and connect the cords to a digital
multimeter (C).
07sAz-001000A
2. Using the wire insulation as a guide for the
contoured tip ofthe backprobe adapter, gently slide
the tip into the connector from the wire side until it
touches the end of the wire terminal.
3. lf you cannot get to the wire side of the connector
or the wire side is sealed (A), disconnect the
connector and probe the terminals (B) from the
terminal side. Do not force the Drobe into the
connector.
Do not puncture the insulation on a wire.
Punctures can cause Door or intermittent
electrical connections.
(cont'd)
11-5