2003 HONDA CIVIC ECT sensor

VTEC/VTC
Component Location Index
VTC OIL CONTROLSOLENOID VALVETroubleshooting, page 1 1-118Test,page 11-'l27
-gl
:1
iai- r-:
@'-;'
;'l--i -
lt i..,,--tl
€)
,..
'- tt /
. -' '--'-
CAMSHAFT POSITIONICMPI SENSOR ATroubleshooting, page 1 1-121Replacement, Page l'!-128
VTC SOLENOID VALVETroubleshooting, page 1 1-123Removal/lnspection, page 1 1-128
11-117

DTC P0340: CMP Sensor A No Signal
DTG P0344: CMP Sensor A Intermittent
Interruption
1. Reset the ECM (see page '11-4).
2. Start the engine.
ls DTC P0340 and/or P0344 indicated?
YES-Go to step 3.
NO Intermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the CMP sensor A and at the ECM.I
3. Turn the ignition switch OFF.
4. Disconnect the CMP sensor A 3P connector.
5. Turn the ignition switch ON (ll).
6. Measure voltage between CMP sensor A 3P
connector terminal No. 3 and body ground.
CMP SENSOR A 3P CONNECTOR
(BLK/YEL}
Wire side of female terminals
ls there battety voltage?
YES Go to step 7.
NO Check the No. 4 ACG {10A) fuse in the under-
dash fuse/relay box. lf the fuse is OK, repair open in
the wire between the CN4P sensor A and No. 4 ACG
(10A) fuse.I
tG1
123
7. Measure voltage between CMP sensor A 3P
connector terminal No. 1 and body ground.
CMP SENSORA 3P CONNECTOR
Wire side olfemale termina s
ls therc about 5 V?
YES-Go to step 8.
NO-Go to step 10.
8. Measure voltage between CMP sensor A 3P
connector terminals No. 2 and No. 3.
CMP SENSOR A 3P CONNECTOF
;f-;-1 ,o, ,r.*,"r.,
I l1 J l-t
,-or---T--I{8RN/YEL) ni-
ls there battety voltage?
YES Go to step 9.
NO-Repair open in the wire between the Cl\4P
sensor A and G101.1
9. Substitute a known-good CMP sensor A and
recheck.
ls DTC P0340 and/ot P0344 indicated?
YES 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 ECM.I
NO Replace the original CMP sensor A {see page
11-128).t
(cont'd)
11-121

VTEC/VTC
10.
DTC Troubleshooting (cont'd)
Measure voltage between ECM connector terminal
A25 and body ground.
ECM CONNECTOR A 131P)
Wire side of female te.minals
ls there about 5 V?
YES-Repair open in the wire between the ECM(A25) and CMP sensor A.I
NO-Go to step 11.
Turn the ignition switch OFF.
Disconnect ECM connector A (31P)
Check for continuity between ECM connecror
terminal A25 and body ground.
ECM CONNECTON A 131P}
Wire side of femaleterminals
ls tnere continuity?
YES-Repair short in the wire between the ECM(A25) and the CMP sensor A. t
NO Update the ECt\4 if it does not have the latest
software, or substitute a known-good ECM, thenrecheck (see page 1 1-6). lf the symptom/indicationgoes away with a known-good ECM, replace the
original ECM.I
11.
't2.
11-122
DTC P0341: WC Phase Gap
1. Resetthe ECM {see page 11-4).
2. Start the engine.
ls DTC P0341 indicated?
YES Go to step 3.
NO Intermittent failure, system is OK at this time.Check for poor connections or loose terminals atthe CMP sensor A and at the ECM.I
3. Check the VTC oil control solenoid valve (see page
11_127]-.
Isthe VTC oil control solenoid valve OK?
YES-Go to step 4.
NO-CIean the VTC oil control solenoid valve, orreplace it (see page 11-'l27l.a
4. Remove the head cover, and check the cam chain
{see page 6-12).
ls the cam chain OK?
YES Go to slep 5.
NO Replace the cam chain (see page 6-12).1
5. Check the VTC actuator (see page 6-8).
ls the VTC actuator OK?
YES- U pdate the ECM if it does not have the tatest
soflware, or substitute a known-good ECI\4, thenrecheck (see page 11-6). lf the symptom/indicationgoes away with a known-good ECM, replace the
original ECM.I
NO- Replace the VTC actuator.l

VTEC/WC
1.
CMP Sensor A Replacement
Remove the air cleaner (see page 1 1-162).
Disconnect the CMP sensor A 3P connector.
Remove the CMP sensor A (A).
Installthe sensor in the reverse order of removal
with a new o-ring (B).
B-'-----'-l:,",14*
11-128
WEC Solenoid Valve Removal/
Inspection
1.Disconnect the VTEC solenoid valve 2P connector.
Measure resistance between VTEC solenoid valve
connector terminals No. 1 and No. 2.
Resistance: 14-30 Q
3. lf the resistance is within specifications, remove the
VTEC solenoid valve assemblv (A)from the
cylinder head, and check the VTEC solenoid valve
filter (B)for clogging. lf it is clogged, replace the
solenoid valve filter, the engine oilfilter, and the
engine oil.
6x1.0mm9.8 N.m (1.0 kgf.m, 7,2 lbf.ftl
L

DTC Troubleshooting
DTC P0451: FTP Sensor Range/Performa nce
Problem
Special Tools Required
Vacuum Pump/Gauge, 0-30 in. Hg A973X-041-XXXXX
1. Remove the fuel fill cap.
2. Turn the ignition switch ON (ll)
3. l\4onitor fuel tank pressure (FTP) sensorvoltage
with the Honda PGM Tester, or medsure voltage
between ECM connectorterminals E4 and E14.
ECM CONNECTOR E 131P)
Wire side of female terminals
ls there about 2.5V?
YES-Go to step 4.
NO Replace the FTP sensor.I
Turn the ignition switch OFF.
Disconnect the hose between the EVAP two way
valve and the FTP sensor at the EVAP two way
valve end.
4.
5.
7.
8.
6. Connect a vacuum pump to the open end of the
hose.
Turn the ignition switch ON {ll).
l\4onitor FTP sensor voltage with the Honds PGM
Tester, or measure voltage between ECM
connector terminals E4 and E14, and carefully
squeeze the vacuum pump a little.
ECM CONNECTOR E 13lPI
Wire side of lemale terminals
The voltage should smoothly drop from about 2.5 V
to about 1.5 V. Stop applying vacuum when the
voltage drops to about 1.5 V or damage to the FTP
sensor may occur.
Does the voltage drop to about 1.5 V and hold?
YES Check for misrouted, leaking, or broken FTP
sensor vacuum lines. lf the vacuum lines are 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 Replace the FTP sensor. !
9.
11-171

EVAP System
DTC Troubleshooting (cont'd)
DTC P0452: FTP Sensor Circuit Low Voltage
1. Check the vacuum lines at the FTP sensor for
misrouting, leakage. breakage, or clogging.
Are the vacuum lines OK?
YES Go to step 2.
NO Repair or replace vacuum lines as
necessary. I
2. Reset the ECM (see page 11-4).
3. Remove the fuelfill cap.
4. Turn the ignition switch ON (ll)
5. Monitor FTP sensor voltage with the Honda PGM
Tester, or measure voltage between body ground
and ECM connector terminal E14.
ECM CONNECTOR E 131PI
1 2t3t45o/89
././114tc61./182C21
22123241 t26271/ 2931
TP (LT GRN)
Wire side of female terminals
ls thete about 2.5 V?
YES- Intermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the FTP sensor and at the ECrM.l
NO Go to step 6.
11-172
6. Turn the ignition switch OFF.
7. Reinstallthe fuel fill cap.
8. Disconnect the FTP sensor 3P connector.
9. Turn the ignition switch ON (ll)
10. Measure voltage between FTP sensor 3P connector
terminals No. 1 and No.2.
FUEL TANK PRESSURE SENSOR 3P CONNECTOR
VCgl {YEL/BLU}
Wire side of female terminals
ls there about 5 V?
YES Go to step 1 '1.
NO-Repair open in the wire between the FTP
sensor and the ECM {E5).1

't2.
13.
14.
11. Measure voltage between FTP sensor 3P connector
terminals No. 2 and No.3.
FUELTANK PRESSUBE SENSOR 3P CONNECTOR
FTP (LT GBN)
Wire side of femaleterminals
ls there about 5 V?
YES - Replace the FTP sensor. t
NO-Go to step 12.
Turn the ignition switch OFF.
Disconnect ECM connector E (31P),
Check for continuity between FTP sensor 3P
connector terminal No. 3 and body ground.
FTP SENSOR 3P CONNECTOB
FTP (LT GRNI
Wire side of femalelerminats
ls there continuity?
YES Repair short in the wire between the FTP
sensor and the ECI\4 {E14).I
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/indicationgoes away with a known-good EClvl, replace the
original ECM.I
DTC P0453: FTP Sensor Circuit High Voltage
1. Check the vacuum lines at the FTP sensor for
misrouting, leakage, breakage, or clogging.
Are the vacuum lines OK?
YES-Go to step 2.
NO Repair or replace vacuum lines as
necessary.I
2. Reset the ECM {see page 11'4).
3. Remove the fuel fill cap.
4. Turn the ignition switch ON (ll).
5. lvlonitor FTP sensor voltage with the Honda PGM
Tester, or measure voltage between body ground
and ECM connector terminal E'14.
ECM CONNECTOR E 131PI
112134567I9
56/ t182C21
242il./29 3031
TP {LT GRN}
Wire side of female terminals
Is there about 2.5 V?
YES Intermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the FTP sensor and at the ECM.I
NO Go to step 6.
{cont'd)
11-173

EVAP System
DTC Troubleshooting (cont'dl
6. Turn the ignition switch OFF.
7. Reinstall lhe fuel fill cap.
8. Disconnect the FTP sensor 3P connector.
9. Turn the ignition switch ON (ll).
'10. l\4easure voltage between FTP sensor 3P connector
terminals No. 1 and No.2.
FTP SENSOR 3P CONNECTOR
VCC3 (YEL/BLU)
Wire side of female terminals
ls there about 5 V?
YES Go to step 11.
NO-Repair open in the wire between the FTP
sensor and the ECM (E4). !
11-174
11, Measure voltage between FTP sensor 3P connector
terminals No.2 and No.3.
FTP SENSOR 3P CONNECTOR
FTP ILT GRN}
Wire side of female terminals
ls there about 5 V?
YES Replace the FTP sensor.l
NO Go to step 12.
l\4easure voltage between ECM connector
terminals E4 and E 14,
ECM CONNECTOR E (31P)
Wire side of female terminals
ls there about 5 V?
YES Repair open in the wire between the FTP
sensor and the ECM (E14).I
NO Update the ECM if it does not have the latest
software, or substitute a known-good ECN4. then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM.I
\