fuel tank air hose HONDA CR-V 2000 RD1-RD3 / 1.G Workshop Manual

Emission Control System
Evaporative Emission (EVAP) Controls (cont'd)
99 - 00 models:
The scan tool indicates Diagnostic Trouble Code {DTC) P0451: The Fuel Tank Pressure sensor circuit range/oerformance Droblem.
ECM/PCM CONNECTORS
SG2 {GRN/BLK)
Wire side of {emaleterminals
FUEL TANKPRESSURESENSOR
VACUUMPUMP/GAUGE.0 -30 in.H9A973X - 041 -
XXXXX
- The MIL har been rooort€d on.- DTC P0451 b storod.
Check lor th6 tu6l tank pr€ssurelen30r:1. Do the ECM/PCM Reset Proce,oure.2. Remove the fuelfill cap.3. Turn the ignition switch ON (ll).4. Monitor the FTP Sensor voltage with the Honda PGMTester, or measure voltagebetween ECM/PCM connectorterminals A29 and C18.
Chock tho vacuum lin6s torrGlriction o. blockago repair asnecessary. lf OK, roplace the fueltank Drer3ur€ sentor.
ls there approx. 2.5 V?
Check for the fuel tank piessureSensot:L Disconnect the hose betweenthe EVAP two way valve andthe fuel tank pressure sensor atthe EVAP two way valve end.2. Connect a vacuum pump tothe open end ofthat hose.3. Turn the ignition switch ON (lll.4. Monitor the FTP S€nsor volt-age with the Honda PGMTester, or measure voltagebetween ECNI/PCNI connectorterminals A29 and C18, andcarefully appiy vacuum on thehose one stroke at a time.5. The voltage should smoothlydrop from the staning approx.2.5 V down to approx. 1.5 V.STOP applying vacuum whenthe voltage drops to approx.1.5 V or damage to the tueltank pressure sensor may
Does the voltage drop to approx.1.5 V and hold?
Intermittent tailuro. sv3tem is OKat this tim€. Chack to. poor con-n€ction6 or 10036 hose at fu6ltank pres3ure ionsor and fueltrnk.
a t32Pl
PTANK ILT GRNI
WAY VALVE
11-208
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Emission Control System
Fuel tank pros3ure sensor tost.(The continuetion of DTC Pl456t.oubls3hooting.,
Chock the tusl trnk pr€3sure sen-sor:1. Remove the fuel fill csp.2. Turn the ignition switch ON fll).3. Monitor the FTP Sensor voh-age with th€ Honda PGMTester, or measure voltagebetween ECM/PCM conn€ctorterminals A29 and C18.
Choct ths vacuum linsr forra3triction o. blockago ropair a!nect*rary. It OK, replaca the fu6ltank praituJc sentot.
ls there approx. 2.5 V?
Check the fuel t nk pressuae 3en-sor:1. Turn the ignition switch OFF.2. Disconnect the hose betweenthe EVAP two way valve andthe tueltank pressure sensor atthe EVAP two way valve end.3. Connect a vacuum pump tothe open end ofthat hose.4. Turn the ignition switch ON 0l).5. Monitor the FTP Sensor volt-age with the Honda PGMTestet, or measure voltagebetween ECM/PCM connectorterminals 429 and C18, andcarefully apply vacuum on thehose one stroke at a lime.6. The voltage should smoothtydrop from the staning approx.2.5 V down to approx. 1.5 V.Stop applying vacuum whenthe voltage drops to approx.1.5 V or damage to the fueltank pressure sensor fiayoccur,
Fu.l tank pressu.c a€nlor b OK.Oo thc EVAP pulge controlsolenoid valve toat (3€€ prgo 11-2151.
Does the voltage drop to approx.1.5 V and hold?
Evaporative Emission (EVAPI Controls (contd)
lP14s6l("ont,a)
ECM/PCM CONNECTORS
SG2 IGRN/BLKI
Wire side oI female terminals
FUEI- TANKPRESSURESENSOR
VACUUMPUMP/GAUGE,0 - 30 in.HgA973X - ill -
xxxxx
EVAP TWOWAY VALVE
11-214
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Emission Control System
Evaporative Emission IEVAPI Controls (cont'd)
lTi,t56l ("onto)
Vacuum hoses and connectionstelit.(The continuarion of DTC P1456troubleshooiing.l
Check the vacuum ho3es andconnect|ons:Check the following parts forleaks at atmospheric p ressu re{see page 11-204).. Fueltank. Fuel fill cap. Fuelfill pipe. EVAP two way valve. Fueltank pressure sensor
Repair or replaco the parts.
Substitute a known-good ECM/PCM and recheck. lf symptom/indication goes away, replac€the original ECM/PCM.
11-218
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Canbter system leak test
{The continuation of DTC P1457
trouble3hootin9.)
Chock the EVAP control canistervent shut valve line and connoc'
tonS:1. Turn the ignition switch OFF
2. Connect to three'way tee fit_
tings into the hose from the
EVAP control canister to the
EVAP two way valve. Connect
the fuel tank pressure sensor
to one of the tee fittings and
the vacuum PumP to the other'
3. Remove the vent hose from
the EVAP control canister vent
shut valve and cap the Pon to
seal the fresh air vent Ior the
EVAP control canister.4. Turn the ignition switch ON (ll).
5. While monitoring the FTP
Sensor voltage with the Honda
PGM Tester, or measurangvoltage between ECM/PCM
connector terminals A29 and
C18 slowly PumP the vacuumpump using a stroke every 1 -
2 seconds.6. Continue to PumP vacuum
until that voltage droPs to
approx. 1.5 V.NOTE: Make sure that the
engine coolant temPeraturestillabove 95'F (35'Cland Yourvacuum PumP has no leak
7. Monitor that voltage for 20
seconds.
Check the EVAP Pu.ge control
solenoid valve line and connec-
tions:1. Turn the ignition switch OFF.
2. Disconnect the Purge lane
hose from the EVAP control
canister and Plug the Port3. Turn the ignition switch ON (lli.
4. While monitoring the FTP
Sensor voltage with the Honda
PGM Tester, or measuringvoltage between ECM/PCM
connector terminals A29 and
Cl8 slowly PumP the vacuumpump using a stroke every 1 -
2 seconds.5. Continue to pump vacuum
until that voltage droPs to
approx. 1-5 V.NOTE: Make sure that the
engine coolant temPeraturestill above 95'F (35"C) and Yourvacuum pump has no leak-
6. Monitor that voltage tor 20
seconds.
Doesthe voltage drop to 1.5 V
and holds at least 20 seconds?
lGp€ct the EVAP control cani3tel
vent 3hut valvo line and connec_
tion5.
Inlpect tho EVAP Putge control
solenoid valvo line and connec'
tion3. It th6y lro OK, do the EVAP
two way valve te3t (seo page 11-
2211.
Does the voltage drop to 1.5 V
and holds at least 20 seconds?
Reolace the EVAP conirol canister.
EVAPBYPASSSOLENOIDVALVE
FUEL TANK
EVAPCONTROL
VENTSHUTVALVE
EVAPCONTROLCANISTER
SENSOR
EVAP TWO WAYVALVE
EVAPTHREE
VALVE
ttrrL
ta
VACUUMPUMP/GAUGE,0 - 30 in.HgA973X -
041 -
XXXXX
FITTINGS
ECM/PCM CONNECTORS
A {32P)
PTANK ILT GRN)
c (31Pt
SG2 {GRN/BLK)
Wire side of female terminals
{cont'd)
11-223
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