2000 HONDA CIVIC evap

Emission Control System
Evaporative Emission (EVAP) Gontrols (cont'd)
'99 - 0O models only:
The scan tool indicates Diagnostic Trouble Code (DTC) P0451: The Fuel Tank Pressure sensor circuit range/oerformance Droblem.
ECM/PCM CONNECTORS
wire side ot femare terminars sG2 IGRN/BLK)
FUEL TANKPRESSURESENSOR
VACUUMPUMP/GAUGE,0 - 30 in.Hg
FUEL TANKPRESSURE SENSORASSEMBLY
EVAP TWOWAY VALVE
IJ
tl'
Ths MIL has been reDortgd on.DTC m/$1 i3 stored.
Check the tuel tank pros3ure ser|-sor:1. Do the ECM/PCM Reset Proce-dure.2. Remove the tuellill cap.3. Turn the ignition switch ON (ll).4. N4onitor the FTP Sensor volt-age with the Honda PGMTester, or measure voltagebetween body ground andECN4/PCM connector terminalsA29 and C18.
ls there approx. 2.5 V7
Check tho tuel tank pressure !on-soa:1. Remove the fuel tank (seepage 11 2421.2. Remove the fuel tank pres-sure sensor assembly fromthe fueltank.3. Connect the fuel tank PressureSensor sub-harness 6P con-nector to the access panelside connector,4. Disconnect the hose betweenthe EVAP two way valvg andthe fuel tank pressure sensor atthe EVAP two way valve end.5. Connect a vacuum pump tothe open end ofthat hose.6. Turn the ignition switch ON (ll).7. Monitor the FTP Sensor volt,age with the Honda PGMTester, or measure voltagebetween ECM/PCM connectorterminals A29 and C18, andcarefully pump vacuum on thehose one stroke at a time.8. The voltage sho!ld smoothlydrop from the stading approx.2.5 V down to approx. '1.5 V.STOP applying vacuum whenthe voltage drops to approx. 1.5V or damage to the fuel tankpressure sensor may occur.
Does the voltage drop toapprox. 1.5 V and hold?
Sub3titute a known-good ECM/PCM and r6check. It symptom/indicltion 90e3 aw.y, replac\. th€original ECM/PCM.
A (32P)
A973X - 041 -
xxxxx
11-274

Emission Control System
Evaporative Emission (EVAP) Controls (cont'dl
!
FUEL TANKPRESSURE SENSOR3P CONNECTOR {C7921
PTANK
{LT GRN)
sG2{GRN/BLK)
Wire side of f€mal€ terminals
{From page 11-275)
Check to. ! short in the wiroIPTANK linol:Measure voltage between thefirel tank pressure sensor 3P con-nector No. 3 terminal and No. 2terminal,
ls there approx.5 V?
Check fo. a Short in the wireIPTANK IinoI:1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con,nector D 116P).3. Check for continuity betweenthe fuel tank pressure sensor3P connector No.3 terminalsand body ground.
Repair thort in thc wire betweantho fuel iank pre$uro 3€naor andECM/FCM tDl5t.
ls there continuity?
Substitute ! known-good ECM/PCM and recheck. lf .ymptom/indication go6s awry, repleco th6origin.l ECM/PCM.
PTANK{LT GRNI
-276

Emission Control System
Evaporative Emission (EVAPI Controls {cont,dlJ
FUEL TANKPRESSURE SENSORSU8-HABNESS6P CONNECTOR 1C574 tC568)rt
PTANK
{LT GRN}
PTANK
ILT GRN}
Wire side of female terminals
(From page 11-277)
Check for a short in the wire{PTANK line):At the access panel side, measure voltage between the fueltank pressure sensor sub-harness6P connector No. 2 terminal andNo. 6 terminal.
ls there approx. 5 V?
Chock lor a Short in the wi.e(PTANK line):1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector A (32P).
3. Check for continuity betweenthe fuel tank pressure sensorsub-harness 6P connector No.2 terminals and body ground.
Repair short in the wi.e betwsenthe luel tank pressure sensor andECM/PCM {A291.
Subsiitute a known-good ECM/PCM and rechock. lf symptom/indication goes away, replac€ theoriginal ECM/PCM.
11-278

Emission Control System
Evaporative Emission (EVAPI Controls (cont'dl
\v
ECM/PCM CONNECTOR D {16PI
PTANK
{LT GRN)SG2 (GRN/BLK}
Wire side of female terminals
lFrom page 11-2791
Check for an open in the wire{PTANK line):Measure voltage between ECM/PCM connector terminals D15and D]1.
Repair open in the wire betweenECM/PCM lD15) and luel tankpressuae sensor.
ls there approx. 5 V?
Substitute a known'good ECM/PCM end recheck. lt symptom/indication goes awav, replace theoriginal ECM/PCM.
-2AO

Emission Gontrol System
(From page 11-281)
Check tor an open in th€ wire(PTANK line):Measure voltage between ECM/PCi/l connector terminals A29and C18.
Repsir open in tho wire betweenECM/PCM {A29} .nd fuol tankoao!3uro tensor.
ls there approx. 5 V?
Substitute a known-good ECM/PCM and rscheck. It symptom/indication goes aw.y, ..plsc. theoriginal ECM/FCM.
Evaporative Emission (EVAP) Controls (cont'd)
IJ
ECM/PCM CONNEfiORS
a {32P)
SG2 IGRN/BLK)
Wire sade of female terminals
tI
a
PTANK ILT GRNI
11-282
\"

\
t,96 D16Y8 engine (coup6l,'9? Dl6Y7 engine (coupe: KL model, sedan: KL (LX) model)"g7 Dl6Y8 ongine (coupe: all mod-
els, sedan: KL model,'98-8ll modelsl 39 - 00 Dl5Y5 engine with M/Tl:
The scan tool indicates Diagnostic Trouble code (DTc) P1456: Evaporative Emission (EVAP) control system leak
detected (fuel tank sYsteml
The scan tool indicates Diagnostic Trouble Code (DTC) P1457: Evaporative Emission (EVAP) control system leak
detected (EVAP control canister system).
Fr4t6l
fF14s7
Possible Causs
. Fuel fill cap
. Vacuum Connections
. Fuel Tank
. EVAP Control Canister Vent Shut Valve
. EVAP Control Canister Vent Shut Valve Circuit
. EVAP Purge Control Solenoid Valve
. EVAP Purge Control Solenoid Valve Circuit
. EVAP Bypass Solenoid Valve
. EVAP Bypass Solenoid Valve Circuit
. Fuel Tank Pressure Sensor
. Fuel Tank Pressure Sensor Circuit
. EVAP Control Canister
. Throttle Body
Troublsshooting Flowchart
VACUUMPUMP/GAUGE,0 - 30 in.HgA973X - 041 -
xxxxx
I
EVAPCONTROL
.4, cANrsrER
re ./ VALVE
{S----r*::n
\(cont'd)
- The MIL ha3 been rePofted
on.- DTC P1456 or P1457 is stored.
Check the EVAP control canbtol
vent shut valve:1. Disconnect the vacuum hose
Irom the EVAP three waY
valve and connect a vacuurnpump to the hose.
2. Remove the EVAP control
canister vent shut valve Irofi
the canrster.3. Turn the ignition switch ON (lli
4. Apply vacuum to the hose.
Chock for . shon in the wire(VSv linel:Disconnect the 2P connector {rom
the EVAP control canister vent
Does the valve hold vacuum?
Repair short in the wir€ betwcen
the EVAP control canister vent
shut v.lve and tho ECM/PCM
tA29|.
Does the valve hold vacuum?
Check the EVAP control canister
vent shui valve:1. Turn the ignition switch OFF.
2. Connect ECM/PCM connectorterminal A29 to body ground
with a iumPer wire.
3. Turn the ignition switch ON (ll).
4. Applyvacuum to the hose
Reohce the EVAP control canis-
ter vent shttt valve.
Does the valve hold vacuum?
ECM/PCM CONNECTOR A {32P)
37I9t01t't2t3t5t6ItItt9202a2a
25aA
ILT GRN/W{T) I JUMPER WIRE
Wire side of femll terminals
(To page 11-284i(To page 11 284)
11-283

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.
PGT (BLKI
:lI23l'ltl'l lelsl ro Ir I1213t6€lnltlr@/lzzl zs f il
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)