ect sensor HONDA CIVIC 1998 6.G Workshop Manual

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

\J
Fuel Tank Pro3sure sensor 196 D16Y8 engine (coupe).'97 D15Y7 engine {coupe: KL model, sedan: KL (LX) modeu,'97
D16Y8 engine (coupe: all models, sedan: KL model, '98-all models) '99 - 00 D16Y5 engine with M/Tl:
\
PTANK
{LT GRNI
vcc2(YEL/BLU}
Wire side oI female terminals
FUEL TANKPRESSURE SENSOR3P CONNECTOR (C7921
sG2IGRN/8LK)
Foc2l::il":"toolindicatesDiagnosticTroublecode(DTc)P0452:A|owvo|tageprob|emintheFue|TankPressure
The fuel tank pressure sensor converts fuel tank absolute pressure into electrical signals and inputs the EcM/PCM.
OUTPUTVOLTAGEtvt4.5
-? kPa(-50 mmHg,-2 in.Hg)
ECM/PCM CONNECTOR O I16P)
Wire side of female terminals
+7 kPs150 mmHg,2 in.Hg)
PRESSURE
(cont'd)
11-275
- The MIL has been reported on- DTC P0452 is stored.
Check the vacuum lines:
Check the vacuum lines of the
fuel tank pressure sensor for mis-
routing, leakage, breakage and
cloggrng.
Are the vacuum lines OK?
Problem v€ritication:1. Do the ECM/PCM Reset Proce
dure.2. Remove the luel fill caP.
3. Turn the ignition switch ON lll)4. Monitor the FTP Sensor volt_
age with the Honda PGM
Tester, or measure voltage
between bodY ground and
ECM/PCM terminal Dl5.lntermittent tailuro, sYstem i5 OK
dt this timo. Chock for Poot con-
neciion3 or loose wir* at C131
llocatod under right side ot dashl,
C4O1 (located .bove under'da3htuso/ielay box), C574 1C568)*
{located under acc€ss Panell.C792 lfuel tank pressule sen3or)
and EcM/PCM.
ls there approx. 2.5 V?
Check tol an op€n in wite (VCC2
line):1. Turn the ignition switch OFF
2. Reinstallthe fuel fill caP.3. Disconnect the fuel tank Pres'sure sensor 3P connector-4. Turn the ignition switch ON (ll)
5, Measure voltage between the
fuel tank pressure sensor 3P
connector No. l terminal and
No. 2 terminal.
Repair open in the wite betweenthe fuel tank Pr€s3ure a€n3or andth6 EcM/PcM (D1ol.ls there approx. 5 V?
(To page 11'276)

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

\
'99 - 00 models excepi Dl6Y5 engine with M/T:
The scan tool indicates Diagnostic Trouble Code (DTC) P0452: A low voltage problem in the Fuel Tank Pressure
sensor.
The fuel tank pressure sensor converts fuel tank absolute pressure into electrical signals and inputs the ECM/PCM
OUTPUTVOLTAGE(vlt.5
0.5-7 kP.(-g) mmHg,-2 in.Hgl
+7 kP.
150 mmHg,2 in.Hgl
PRESSURE
I
Wire side of lemale terminals
FUEL TANKPRESSURE SENSORSUB.HARNESS6P CONNECTOR (C574 (C568)rl
vcc2(YEL/BLUIsG2{GRN/BLK}
Wire side o{ temale terminals
The MIL has been .eported on.
DTC P0452 is stored
Check the vacuum lines:
Check the vacuum lines of the
fuel tank pressure sensor lor mis-
routing, leakage, breakage and
cloggrng.
Are the vacuum hnes OK?
Problem veritication:1. Do the ECM/PCM Reset Proce-
du re,2. Bemove the fuel fill caP.
3. Turn the ignition switch ON {ll)
4. Monitorthe FTP Sensor voltage
with the Honda PGM Tester' or
measure voltage between body
groLrnd and ECM/PCM connec_
tor terminalA29.
lntermitlent tailure, 3Ystem b OK
at this time. Check for Poor con'
nections or loose wire3 at C131
{located under right side of dash},
C401 {located above under'dash
tuse/relay box), C574 (C568)*
llocdted under access Panel),C792 (tuel rank Prcssure sensorl
and ECM/PCM.
ls there approx.2 5 V?
Check for an open in wire {VCC2
line):1. Turn the ignition switch OFF.
2. Reinstall the ltrel fill caP
3, Remove the access Panel from
the floor.4. Disconnect the fuel tank Pres'sure sensor sub-harness 6P
5. Turn the ignition switch ON (ll).
6. At the access Panel side, mea_
sure voltage between the fuel
tank Pressure sensor sub-nar-
ness 6P connector No 5termi
nal and No. 6 termlnal.
Repair open in tho wire between
th6 fu€l tank Prossuro sen3oa and
the ECM/PCM lc28).ls there approx 5 V?
ECM/PCM CONNECTOR A (32P)
PTANK {LT BLUI
I
ll
(To page '11-278)
(cont'd)

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

\
Fue| Tank Pr€ssure sensor 196 Dr6Y8 engine (coupe},,97 D16Y7 angino (coupo: KL mode|' 3edan: KL (Lxl modg||',97
Dl6Y8 engine (coupe: all modeb, sedan: Ki model.'98'all modols) 39 - 0O Dl6Y5 ongins with M/Tl:
rFoG'l::;Jl"too|indicatesDiagnosticTroub|ecode(oTc)P0453;Ahighvo|tageprob|emintheFue|TankPressure
ECM/PCM CONNECTOR D Il6PI
PTANKILT GRNI
\
Wire side of tgmale torminals
FUEL TANKPRESSURE SENSOR3P CONNECTOR (C792)
vcc2(YEL/BLU}
sG2(GRN/BLKI
Wire sid€ of female terminals
I
sG2IGRN/BLKI
PTANKIGBN/RED}
(cont'd)
11-279
The MIL has beon reponed on
DTC P0453 b stored.
Check the vacuum lines:
Check the vacuum lines oI the
fueltank pressure sensor for mis-
routing, leakage, breakage and
clogging.
Are the vacuum lines OK?
Problem verification:1. Do the ECM/PCM Reset Proce-
dure.2. Femove the fuel fill cap
3. Turn the ignition switch oN (ll).
4. Monitor the FTP Sensor volt-
age with the Honda PGM
Tester, or measure voltage
between bodY ground and
ECM/PCM connector termrnal
D15.
lntormittont t iluro, 3Ystem is OK
at this time. Check lot Poor con_
noctiona or loo3e wirat at C131
{loc.ted undor right 3id6 of d8hl,
CaOl llocatod rbov. under-dalh
fus6/relay boxl, C574 (C568lr
llocatod und6l accoss Pan6ll,C792 lfuel tank Preasulo aonlorl
end ECM/PCM.
ls there approx. 2 5 V?
Check for an oPen in the wire(SG2line):1. Turn the ignition switch OFF.
2. Reinstall the fuellill cap
3. Disconnect the fuel tank Pres-sure sensor 3P connector.
4. Turn the ignition switch ON (ll)
5. Measure voltage between the
fuel tank Pressure sensor 3P
connector terminals No. 1 and
No.2.
Ropair opon in the wira b€tw€sn
the fuel tank prasure sonlor and
ECM/PCM (Dl1).ls there aPProx. 5 V?
Check for an open in the wire(PTANK line):Measure voltage between the
fueltank Pressure sensor 3P con-
nector No. 3 terminal and No. 2
termrnal,
ls there approx. 5 V?
*: coupe
{To page 11-280)

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

\
'99 - 0O modols except Dl5Y5 engine with M/T:
rFo45'::n":"tooIindicatesDiagnosticTroub|ecode(DTc)P0453:Ahighvo|tageprob|emintheFUelTankPressure
Wire side of temale terminals
FUEL TANKPRESSUNE SENSOR
SUB.HARNESS6P CONNECTOR {C574 (C568)}}
vcc2{YEL/BLUI
sG2IGRN/BLK)
Wire side of female terminals
PTANK{LT GRNI
(cont'd)
11-281
ECM/PCM CONNECTOR A {32P)
PTANK {LT GRN)
The MIL has been reported on.
DTC P0453 is stored.
Check the vacuum lines:
Check the vacuum lines ot the
fuel tank pressure sensor for mis-
routing, leakage, breakage and
clogging.
Are the vacuum lines OK?
Problem verilication:1. Do the ECM/PCM Reset Proce-
du re,2. Remove the fuel fill caP
3. Turn the ignition switch ON (ll).
4. Monitor the FTP Sensor volt'
age with the Honda PGM
Tester, or measure voltage
between body ground and
ECM/PCM connector terminalA.29.
lntermittent failuro. svstem b OK
at this time. Check for Poor con_
noctions or loo3€ wire3 at C131
{located under tight side of dash),
C4Ol {located above underdash
fuse/relay boxl, C57{ (C5681'
llocaled unde. access Panell,C792 {fuel tank Pressure sensorl
aod ECM/PCM.
ls there approx.2.5 V?
Ch€ck for an open in the wira
{SG2line):1. Turn the ignition switch OFF.
2. Reinstall the fuel fill caP
3. Remove the access Panellrom the floor.
4. Disconnect the fuel tank Pres-sure sensor sub-harness 6P
5. Turn the ignition switch ON (ll)
6, At the access Panelside, mea-
sure voltage between the fuel
tank pressure sensor sub_har-
ness 6P connector termlnals
No.5 and No.6.
Repair open in the wire between
the fueliank Pres3ure 3ensor and
ECM/PCM {Cl8).ls there approx.5 V?
Check lor an oPen in the wire
{PTANK linel:At the access Panel side, mea
sure voltage between the fuel
tank pressure sensor suo_harness
6P connector No. 2 terminal and
No. 6 terminal.
ls there approx. 5 V?
(To page 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