1996 HONDA CIVIC PCM

Emission Control System
Evaporative Emission (EVAPI Controls (cont'dl
1
EVAP CONTROLCANISTER VENT SHUTVALVE 2P CONNECTOR IC141}
lltrt+ rcl
o) (8LK/YErl
I
temale terminalsWire side ot
ECM/PCM CONNECTOR A (32PI
VSV ILT GRN/WHT}
'l'
Wiro side of lemaletgrminals
VACUUMPUMP/GAUGE,0 - 30 in.Hg4973X -
041 - XXXXX
(From page 1l-283)
{To page 1l-285}
Check the vacuum whon cold:1. Disconnect the vacuum hoseshown from the EVAP controlcanrster and connect a vacuumgauge to the hose,2. Start the engine and allow itto idle.NOTE: Engine coolant tem-perature must be below 154oF(68'C) or lVC switch OFF.3. Ouickly raise the engine speedto 3,000 rpm.
(From page l1-283)
Check for an open in tho wire(lGl line):1. Turn the ignition switch OFF.2. Disconnect the 2P connectorlrom the EVAP control canis-ter vent shut valve.3. Turn the ignition switch ON (ll).4. Measure voltage between theEVAP controlcanister vent shutvalve 2P connector terminalNo. 2 and body ground.
Repair open in the wire betwe€nthe EVAP control c.ni3tei ventshut valve and th6 No. 15 ALTER-NATOR SP SENSOR 17.5 Al fuse.
Cfisck tor an opon in the wire (VSVline):1. Turn the ignition switch OFF.2. Beconnect the 2P connectorto the EVAP control canistervent shut valve.3. Turn the ignition switch ON (ll).4. Measure voltage betweenECM/PCM connector termi-nals A29 and Al0.
Rep.ir open in the wire betwoonthe EVAP control canister ventshut valve and th€ ECM/PCMtA29t.
ls there battery voltage?
Replace th6 EVAP control canis-ter vent 3hut valve.
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25
11-284

\
\
(From page 11-284)
\(cont'd)
11-285
EVAP PURGE CONTROL SOI.INOID
VALVE 2P CONNECTOR IC114I
Wire side otfemaleterminals
?,
I,l,lil?"",,,u
EL,TWYEL)
Check the EVAP pirrge controlsolenoid valvei1. Disconnect the 2P connector
lrom the EVAP purge control
solenoid valve.
2. Ouickly raise the engine speed
to 3,000 rpm.
ls there vacuum?
InsDect vacuum ho56 routing.ll OK, replace the EVAP Purgecontrol solenoid valve.
Chock for a short in the wire(PCS linel:1. Turn the ignition switch OFF
2. Disconnect ECM/PCM connec'
tor A (32Pi.
3. Check for continuity between
the EVAP PUrge control sole
noid valve 2P connector termi
nal No.2 and body ground.
Check the vacuum when hot:
1. Turn the ignition switch OFF
2. Block the rear wheels and set
the parking brake.3. Jack up the front o{ the vehi-
cle and support it with safety
stands,4. Start the engine. Hold the
engine al 3,000 rpm wlth no
load (in Park or neutral) until
the radiator fan comes on, then
let it idle.5, Check for vacuum at the vac-
uum hose with transmissaonin gear (A/T in B Position,M/T in lst gear) after starting
the engrne.6. Ouickly raise the engine speed
to 3,000 rpm.
Reoair short in the wire botween
the EVAP purg€ cor|t]ol solenoid
valve and the ECM/pcM lA15l.ls there continuity?
Substitute a known-good ECM/
PCM and recheck. lf sYmPtom/indication goes eway. repl.c€ the
original ECM/PCM.
Check the EVAP Purg€ control
solenoid valve:1. Turn the ignition switch OFF
2. Disconnect the 2P connector
from the EVAP Purge control
solenoid valve and warm lt
up to normal operating tem_perature again if necessary
3. Stan the engine.4. At the harness side, measure
voltage between the EVAP
Purge control solenoid valve
2P connector terminal No. 1
and No. 2 with the transmission in gear (A,/T in E Posi-tion, M/T in 1st gear).
In3pect vacuum ho3€ touting.
ll OK, replace EVAP Purge con-
lrol aolenoid vtlv€.
Check lo. an open in the wire
llGl linel:At the harness side, measure volt
age between the EVAP Purge con-
trol solenoid valve 2P connectorterminal No. 1 and body groundRepeir open in tho wire between
EVAP purge conttol solenoid valv€
and the No. 15 ALTERNATOR SP
SENSOR (7.5 A fu3e
IBLK/YELI
lTo page 11 286i(To page 11-286)

Emission Control System
(From page 11 285)
Check lor an op€n in the wire{PCS line}:1. Turn the ignition switch OFF.2, Reconnect the 2P connector lothe EVAP purge control sole-noid valve.3. Turn the ignition switch ON (lll.4. Measure vo ltage betweenECM/PCM connector terminals415 and A]0.
Repai. op€n in the wire bGtweenthe EVAP purge control solenoidvalve and the ECM/PCM {A151.
Substitute a known-good ECM/PCM and retest. tf sympiom/indi-cation goes away, replac6 theoriginal ECM/PCM.
Evaporative Emission (EVAPI Controls (cont'd)
(From page 11'285)
(To page 'l1 287)
\.
ECM/PCM CONNECTOR A {32P}
PCS{RED/YEL)
PGl
{BLK)
Wire side oftemaleterminals
EVAP BYPASSSOLENOID VALVE
O.RINGBeplace.
PUMP/GAUGE,0 - 30 in.HgA973X -
041 -
xxxxx
EVAP TWO WAY VALVE
EVAP IWO WAY
Check the EVAP two way valvo:See EVAP two way valve test (seepage 11'294).
Replace tho EVAP two way valve.
Check the EVAP bypr$ 3olenoid
1. Disconnect the vacuum hosefrom the EVAP two way valveand connect a vacuum pumpto the hose.2. Turn the ignition switch ON lll).3. Apply vacuum to the hose.Check tor a short in the wire{2WBS linel:Disconnect the 2P connector fromthe EVAP bypass solenoid valve.Does the valve hold vacuum?
Repair short in the wire betwe€nEVAP bypass sol€noid valve andrhe ECM/PCM lA28).
Does the valve hold vacuum?
11-286

I
ECM/PCM CONNECTOR A (32P)
2WBS(BLUIWiro side olIemaleterminalsJUMPER _
WIRE
EVAP BYPASS SOLENOIDVALVE 2P CONNECTOR {C793I
Wire side of
femal€terminals
\
ECM/P,CM CONNECTOR a l32Pl
Wir€ side of femaleterminals
(cont'dl
11-2A7
(From page 11-286)
Check the EVAP bypa3s 3olenoid
1. Turn the ignition switch OFF.
2. Connect ECM/PCM connectorterminal A28 and body ground
with a jumper wire.3. Turn the ignition switch ON (ll).ChGck tor an opon in lho wite(lGl lin6l:1. Turn the ignition switch OFF
2. Disconnect the 2P connectortrom the EVAP bypass sole-noid valve.3. Turn the ignition switch ON (ll).
4. Measure voltage between the
EVAP bypass solenoid valve
2P connector terminal No- 1
and body ground.
R.pair open in tha wil€ botwoonEVAP purg. cor|trol 3olenoid valve
.nd tho No. 15 ALTERNATOR SP
SENSOR 17.5 Al tu3e.
Check lor an open in the wire
{2WBS line):l. Turn the ignition switch OFF.
2. Reconnsct the 2P connectorto the EVAP bypass solenoid
3. Turn the ignition switch ON (ll)
4. Measure voltage between
ECM/rcM connector terminalsA28 and Al0.
Ch6ck the following P..ts for
l6akage to atmosPhere, and
roplir or rephco if neca3aary:' fuel fill c.D. tu6l t.nk. tuel vapor pipe. EVAP two way v3lvo. EVAP bypa3! solanoid vtlY., fuel tlnk pra63uro 3on3or. EVAP control canBte.. EVAP control crnistor vent
shut vtlvo. EVAP purgo control lolonoid
. vscuum hoseS and connoction3
Roprir opon in tho wiro betwoen
th. EVAP byp.$ 3ol6noid valve
rnd tho EcM/PcM lA28l.ls there battery voltage?
I2578t011'12tt15t6t8t9202321
2726293o
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Ent ll4al*l 4 l,-'l
2WaS {BLUI
\

Emission Control System
Evaporative Emission {EVAP) Controls (cont'dl
\J
tF1456-l
tP14sz-l
EVAPCONTROLCANISTERVENTSHUTVALVE
O.RINGReplace.
EVAPCONTROLCANISTER
ECM/PCM CONNECTOR A I32PI
(To page 11'289)
'99 - 00 modols except Dl6Y5 engine with M/T:
The scan tool indicates Diagnostic Trouble Code (DTC) P1456: Evaporative Emission (EVAP) control system leak
detected (fuel tank svstem).
The scan tool indicates Diagnostic Trouble Code (DTC) P1457: Evaporative Emission (EVAP) control system leak
detected (EVAP control canister system).
Possible Cause
. Fuel fill cap
. Vacuum Connections
. FuelTank
. EVAP Control Canister Vent Shut Valve
. EVAP Control Canister Vent Shut Valve Circuit
. EVAP Purge Control Solenoid Valve
o EVAP Purge Control Solenoid Valve Circuit
. EVAP Bypass Solenoid Valve
0 -30 in,Hg
. EVAP Bypass Solenoid Valve Circuit
. Fuel Tank Pressure Sensor
. Fuel Tank Pressure Sensor Circuir
. EVAP Control Canister
. ORVR vent shut valve
. ORVR vapor recirculation valve
. Throttle Body
Troubleshooting Flowchart
VACUUMPUMP/GAUGE,A973X - oal -
xxxxx
T-t
t\
The MIL has been reported on.DTC P1456 o. P1457 is stored.
Check the EVAP cont.ol canistervent shul valve:1. Disconnect the vacuum hosefrom the EVAP three wayvalve and connect a vacuumpump to the hose.2. Remove the EVAP controlcanister vent shut valve fromtne canrster.3. Turn the ignition switch ON (ll).
4. Apply vacuum to the hose.Check for a short in the wiro(VSV linel:Disconnect the 2P connector fromthe EVAP control canister ventDoes the vaive hold vacuum?
RoDair 3hort in the wire botwe€nthe EVAP control canilter ventshut valve and the ECM/PCM{A4t.
Does the valve hold vacuum?Check the EVAP cont.ol canisterv€nl shut valve:1. Turn the ignition switch OFF.2. Connect ECM/PCM connectorterminal A4 to body groundwith a jumper wire.3. Turn the ignition switch ON (ll).
4. Apply vacuum to the hose.
Reolace the EVAP control canis-ter veni shut valve.
Does the valve hold vacuum?
Wire side of female terminals
11-288
lTo page 11-289)

\
EVAP CONTROLCANISTER VENT SHUTVALVE 2P CONNECTOR IC141I
Wire side of temale terminals
ECM,/PCM CONNECTORS
tG1IBLK/WHT}
A973X -
0/r1 - XXXXX
Wire side of femaletermrnats
\
?,T-t
fl
VACUUMPUMP/GAUGE, 0 -30 in.Hg
\(cont'd)
11-289
{From page l1 288}
{To page 11-290)
Ch€ck the vac[um when cold:1, Disconnect the vacuum hoseshown from the EVAP controlcanister and connect a vacuumgauge to the hose.2. Start the engine and allow it
to idle.NOTEi Engine coolant temperature must be below 154"F(68'C) or Ay'C switch OFF.3. Ouickly raise the engine speedto 3,000 rpm.
(From page 11-288)
Check for an open in tha wire(lGt linol:1. Turn the ignition switch OFF.2. Disconnect the 2P connectorfrom the EVAP control canis-ter vent shut valve.3. Turn the ignition switch ON lll).4. Measure voltage between theEVAP control canister vent shut
valve 2P connector terminalNo.2 and bodyground.
Repair open in the wire betweenthe EVAP control canister ventshut valve .nd the No. 15 ALTER-NATOR SP SENSOR {7.5 A)fu3e.
ls there battery voltage?
Ch€d( for an op€n in the wiie IVSVlinel:1. Turn the ignition switch OFF.
2. R€connect the 2P connectorto the EVAP control canistervent shut valve,3. Turn the ignition switch ON (ll).
4. Measure vo ltage betweenECM/PCM connector termi-nals A4 and 82.
Repair open in the wire bctweenthe EVAP control canistor ventshut valve and lhe ECM/PCM{44t.
ls there battery voltage?
Rcolaco tho EVAP control canis.t6r vent shut valvo.
a t32P)
-

Emission Control System
Ch€ck the EVAP purge controlsolenoid valv6:1. Disconnect the 2P connectorfrom the EVAP purge controlsolenoid valve.2. Ouickly raise the engine speedto 3,000 rpm.
Insped vacuum hose routing.lf OK. roplace the EVAP purge
control solonoid valve.
Chock tor r short in the wir€
{PCS line):1. Turn the ignition switch OFF.2. Disconnect ECM/PCM connec-tor A (32P).
3- Check tor continuity betweenthe EVAP purge control sole-noid valve 2P connector termi-nal No. 2 and body ground.
Check the vacuum when hot:1. Turn the ignition switch OFF.2. Block the rear wheels and setthe parking brake.3. Jack up the lront of the vehi-cle and support it with safetystands.4. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutrali until
the radiator fan comes on, thenlet it idle.5. Check for vacuum at the vac-uum hose with transmissionin gear (A/T in E position,
lvl/T in 1st gear) after startingthe engine.6. Ouickly raise the engine speedto 3,000 rpm.
Rooair shoft in the wire belwegnthe EVAP pulg6 control solenoidvalvs and tho ECM/PCM {A61.ls there continuity?
Substitute a known-good ECM/PCM and rech6ck. lt 3ymptom/indicrtion 90e3 rway, r6plac6 th€o.iginal ECM/FCM.
Check th€ EVAP purge controlsolenoid valve:1. Turn the;gnition switch OFF.2. Disconnect the 2P connectorfrom the EVAP purge controlsolenoid valve and warm itup to normal operating tem-perature again if necessary.3. Start the engine.4- At the harness side, measurevoltage between the EVAPpurge control solenoid valve2P connector terminal No. 1and No.2 with the transmis-sion in gear {A/T in E posi-tion, M/T in lst geari.
In3pect vacuum hoae routing.lf OK, repl.ce EVAP purge con-trol solonoid valve.ls there battery voltage?
Chock for an open in the wire(lG1 lina):At the harnoss side, measure volt-age beNveen the EVAP purge con-trol solenoid valve 2P connectorterminal No. 1 and body ground.
Repair open in the wire b€lwe€nEVAP purge contrl 3olenoid valv6and lhe No. 15 ALTERNATOR SPSENSOR 17.5 A, fu3e.
ls there battery voltage?
Evaporative Emission (EVAPI Controls (cont'dl
(From page 11-289)
(To page 11-291)
11-290
IJ
EVAP PURGE CONTROL SOLENOIDVALVE 2P CONNECTOR IC114I
PCS
IRED/YEL)
temaletermrnars
of
PCS(RED/YEL)
tGlIBLK/YEL)
{To page 11 291)

IECM/PCM CONNECTOR
I
EVAP TWO WAYVALVE
Wire side oftemaleterminals
FUELTANK
(cont'd)
11-291
tn
VACUUMPUMP/GAUGE,0 - 30 in Hs
A973X - 041 -
xxxxx
(From page l1 290)
Check the EVAP two way valve:
See EVAP two way valve test (see
page 11-295).
Roplace the EVAP two way valve
Check the EVAP bypa$ solenoid
1. Remove the fuel tank (see
page 11-242J.2. LiIt up the fuel tank with a
transmission iack, and connect
the fuel tank pressure sensor
sub harness 6P connector to
the access panel side connec_
tor,3. Disconnect the vacuum hosefrom the EVAP two way valveand connect a vacuum PumPto the hose,4. Turn the ignition switch ON (ll)
5. Apply vacuum to the hose.
(To page 11 292)
(From page 11-290)
Check for an open in the wire
{PCS lin6):1. Turn the ignition switch OFF
2. Reconnect the 2P connector to
the EVAP purge control sole-
3. Turn the ignition switch ON {ll).4. Measu re voltage betweenEClr/PCM connector terminals
A6 and 82.
Ropair open in the wire betweenthe EVAP purge Gontrol solenoidvrlve and th6 ECM/PCM lA6lls there battery voltage?
Substitute a known-good ECM/
PCM rnd re{61. lf symptom/indi'
cation goes away, rePlace the
oiiginal ECM/PCM.