2003 HONDA CIVIC switch

PGM-FI System
MIL Circuit Troubleshooting (cont'dl
11.
Try to start the engine.
Does the engine start?
YES-Go to step 11.
NO-Go to step 14.
Turn the ignition switch OFF.
Connect ECM connector terminal E31 to bodyground with a jumper wire.
10.
12.
ECM CONNECTOR E 13lPI
MIL(GRN/ORN}
Wire side of female terminals
Turn the ignition switch ON (ll).
ls the M lL on?
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 ECIM, replace the
original ECM.I
NO-Check for an open in the wire between the
ECM (E31) and the gauge assembly. Also check for
a blown MIL bulb. lf the wires and the bulb are OK,
replace the gauge assembly.l
Turn the ignltion switch OFF,
Inspect the No. 6 ECU (ECIM) (15A) fuse in the
under-hood fuse/relay box.
ls the f use OK?
YES-Go to step 22.
NO-Go to step 16.
't 4.
15.
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JUMPERWIRE
11-98
to.Remove the blown No. 6 ECU {ECfU) (154) fuse
from the under-hood fuse/relay box.
Remove the glove box (see page 20-63) and the
PGM'FI main relay 1.
Check for continuity between body ground and
PGM-Fl main relay 1 4P connector terminals No. 2
and No. 4 individuallv.
PGM-FI MAIN RELAY 14P CONNECTOR
Wrre srde ol lemale termrnals
ls there continuity?
YES-Repair short in the wire between the No.6
ECU (ECl\4) (15A) fuse and the PGM-Fl main relay 1.
Also replace the No.6 ECU (ECM) (15A) fuse.l
NO-Go to step 19.
17.
18.
fVBv) (wHr/
IA BLK)(

PGM-FI System
MIL Circuit Troubleshooting (cont'dl
37. lvleasure voltage between ECM/PCM connector
terminal E7 and body ground.
ECM CONNECTOR E {31PI
Wire side of female terminals
ls there battery voltage?
YES Go to step 42.
NO Go to step 38.
Turn the ignition switch OFF.
Remove the PGM-FI main relay 1
38.
39.{A}
-A
MRLY
11-102
40. lvleasure voltage between PGN4-Fl main relay 1 4P
connector terminal No. 4 and bodv qround.
PGM-FI MAIN RELAY 1ilP CONNECTOR
41.
ls there battery voltage?
YES-Go to step 41.
NO Repair open in the wire between the No. 6
ECU (ECM) (15A) fuse and the PGfM-Fl main relay 1.
I
Check for continuity between PGM-FI main relay 1
4P connector terminal No. 3 and ECM connector
terminal E7.
PGM.FI MAIN RELAY 14P CONNECTOR
\
ECM CONNECTOR E 131PI
ls there continuity?
YES-Testthe PGM-Fl main relay 1 (see page 22-
51 ). lf the relay is OK, 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 ECM.I
NO*Repair open in the wire between the PGM-FI
main relay 1 and the ECM (E7).1
Wire side ot lemale terminals
MRLY (RED/YEL)
MRLY (RED/YEL)
Wire side of female terminals

42.
43.
44.
45.
46.
Reconnect ECI\4 connector E {31P).
Turn the ignition switch ON (ll).
Measure voltage between body ground and ECM
connector terminals 42 and 43 individually.
Wire side of female terminals
ls there battery voltage?
YES Go to step 51.
NO Go to step 45.
Turn the ignition switch OFF.
Remove the PGM'Fl main relay 1{A)
,A
47. Turn the ignition switch ON (ll).
ECM CONNECTOR A {31PI
49.
50.
48. Measure voltage between PGM-FI main relay 1 4P
connector terminal No. 2 and body ground.
PGM.FI MAIN RELAY 14P CONNECTOR
ls there battery voltage?
YES Go to step 49.
NO Repair open in the wire between the No.6
ECU {ECM) (15A}fuse and the PGM-Fl main
relay 1 . !
Turn the ignition switch OFF.
Check for continuity between PGM-Fl main relay 1
4P connector terminal No. 1 and ECM connector
terminals 42 and 43 individually.
PGM.FI MAIN RELAY IilP CONNECTOR
ls there continuity?
YES Replace the PGM-Fl main relay 1.1
NO Repair open in the wire between the PGM-FI
main relay '1 and the ECM (A2, A3).1
{cont'd}
Wire side of temale terminals
IGPl (YEL/BLK)
Wire side of female terminals
11-103

PGM-FI System
MIL Circuit Troubleshooting (cont'dl
51. Measure voltage between body ground and ECM
connector terminals 44, A5, 423, and 424
individuallv.
ECM CONNECTOR A 131P)
PG2 (BLK) PG1 IBLKI
Wire side of female terminals
ls there morc than 1.0 V ?
YES Go to step 52.
NO-Repair open in the wire(s) that had more than
1.0 V between G 10'l and the ECM (A4, A5, A23,
A24l.a
Measure voltage between body ground and ECM
connector terminal 421.
ECM CONNECTOR A 131P)
Wire side of female terminals
ls there about 5 V?
YES-Go to step 60.
NO-Go to step 53.
11-104
53.
54.
Turn the ignition switch OFF.
Disconnect the manifold absolute pressure (MAP)
sensor 3P connector.
Turn the ignition switch ON (ll).
Measure voltage between body ground and ECM
connector terminal A21.
ECM CONNECTOR A {31P)
Wire side of female terminals
ls there about 5 V?
YES Replace the MAP sensor.l
NO Go to step 57.
Turn the ignition switch OFF.
Disconnect ECM connector A (31P).
55.
56.
\
57.
58.

59. Check for continuitv between ECIM connector
terminal 421 and body ground.
ECM CONNECTOR A {3,IPI
Wire side of female terminals
ls there continuity?
YES*Repair short in the wire between the ECM(421) and the MAP sensor.l
NO Update the ECM it it does not have the latest
soflware, or substitute a known-good ECM, then
recheck (see page 1'l-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM.I
Measure voltage between body ground and ECM
connector terminal 420.
ECM CONNECTOR A {3TP}
60.
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vcc2IYEL/BLU)
Wire side ot female terminals
ls there about 5 V?
YES-Go to step 68.
NO-Go to step 61.
t t,
oz,
63.
64.
Turn the ignition switch OFF.
Disconnect the throttle position (TP) sensor 3P
connector.
Turn the ignition switch ON (ll).
Measure voltage between body ground and ECM
connector terminal 420,
ECM CONNECTOR A 131P)
Wire side of female terminals
ls there about 5 V?
YES Replace the thronle body (the TP sensor is
not available separately). I
NO Go to step 65.
Turn the ignition switch oFF.
Disconnect ECM connector A (31P).
65.
66.
conl o
11-105

PGM-FI System
67.
MIL Circuit Troubleshooting (cont'd)
Check for continuity between ECIM connector
terminal A20 and body ground.
ECM CONNECTOR A (31P)
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o
Wire side of female terminals
ls there continuity?
YES Repair shon in the wire between the ECN4
{A20) and the TP sensor, or repair short in the wire
between the ECM (A8) and the knock sensor. t
NO Update the ECM if it does not have the latest
software. or substitute a known-good ECM, then
recheck (see page l1-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM.t
vcc2{YEL/BLU}
11-106
68. Measure voltage between body ground and ECM
connector terminal E5.
ECM CONNECTOR E (31PI
Is there about 5 V?
YES U pdate the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good EClvl, replace the
original ECM.t
NO-Go to step 69.
Turn the ignition switch OFF.
Disconnect the fuel tank pressure (FTP) sensor 3P
connector.
Turn the ignition switch ON (ll).
69.
70.
11.
Wire side of female terminals

13.
74.
75.
72. Measure voltage between body ground and ECM
connector terminal E5.
ECM CONNECTOR E 131P}
ls there about 5 V?
YES Replace the FTP sensor.t
NO Go to step 73.
Turn the ignition switch OFF.
Disconnect ECM connector E (3'lP).
Check for continuity between ECM connector
terminal E5 and body ground.
ECM CONNECTOR E {31PI
Is there continuity?
YES Repair short in the wire between the ECM(E5) and the FTP sensor.l
NO Update the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indicationgoes away with a known-good ECM, replace the
original ECM.I
Wire side of female terminals
Wire side of female terminals
76.
77.
78.
79.
80.
Turn the ignition switch OFF.
Turn the ignition switch ON (ll).
Measure voltage between ECM connector terminal
E29 and body ground.
ECM CONNECTOR E (31P)
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scstBRN)
Wire side of female terminals
ls there about 5 V (or battery voltage)?
YES-Go to step 82.
NO Go to step 79.
Turn the ignition switch OFF.
Disconnect ECM connector E (31P).
(cont'd)
11-107

PGM-FISystem
MIL Gircuit Troubleshooting (cont'd)
81. Check for continuity between ECM connector
terminal E29 and body ground.
ECM CONNECTOR E 131P}
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14tc61,/1182A21
22123124271./3031
o
scs(BRN)
Wire side of female terminals
ls there continuity?
YES-Repair short in the wire between the data link
connector (DLC) and the ECM (E29).1
NO Update the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECI\4,I
Turn the ignition switch OFF.
Disconnect ECM connector E (31P).
Turn the ignition switch ON (ll).
Does the MIL stay on?
YES-Repair short in the wire between the gauge
assembly and the ECM (E31 ). lf the wire is OK,
replace the gauge assembly.l
NO 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 ECM.I
11-108