engine speed HONDA CR-V 1997 RD1-RD3 / 1.G Service Manual

Vehicle Speed Sensor (VSSI
lPosoo-]-'. |posol l-'
'97 modol:
The scan tool indicates Diagnostic Trouble Code {DTC} P0500*'or P0501*r: A range/perfor-
mance in the Vehicle Speed Sensor (VSS) circuit. * I ; A/T*2i Mfi
FCM CONNECTORS
A t32Pl
LG1(BRN/BLK)
NOTE: Do not use the engine to turn thofront wheels with th6 rear wheels on theground. The 4WD system will engage andthe vehicle will suddenlv Iurch forward.
Wire side ot female terminals
LGl
{BRN/BLKI
(cont'd)
11-135
The MIL hes boen roported on.DTC m501 is 3tor€d.
Problom verificetion:1. Test'drive the vohicle.2. Check the vehicle speed withthe scan tool,
lntormittent tailure, rystom b OKat thia timo. Chock tor poor con-nection3 or 10o3o wires rt C129lvss) .nd rr rhe Pcfr4,
ls the correct speed indicated?
Chock for an open in tho PiCM:1. Turn the ignition switch OFF.2. Block the rear wheels and setthe parking brake.3. Jack up the lront of the vehicleand support it with saletystands.4. Turn the ignition switch ON (ll).
5. Elock the right front wheel andslowly rotate the left trontwheel by hand.6. Measure voltage betweenPCM connector terminals C18and A9.
Substitulc a known-good PCMand .och6ck. It symptom/indicd.tion go.a away, .cplaco tho origi-nel FCM.
Doesthe voltage pulse 0 Vand 5 V or battery voltage?
Check for a .hort in the PCM:L Turn the ignition switch OFF.2. Disconnect the PCM con'nector C (31P).
3. Turn the ignition switch ON (ll).
4. Elock the right front wheeland slowly rotate the left front
5. Measure vohage between PCMconnector terminals C18 andA9.
Substituto e known-good PCMand rochock. f rymptom/indica-tion goos rwry, roplsc. tho origi-nalFCM.
Doesthe voltage pulse 0 Vand 5 V or battery voltage?
- Repair short in the wirebetween the PCM lC18l,cruise control unit, speodo-meter, and VSS,- Repair opon in the wirebetween the PCM {C181 .ndrhe vss.- f wire is OK. tost lho VSS l3oosoction 231.
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PGM-FI System
Vehicle Speed Sensor (VSSI {cont'd}
'98 - 00 models:
ECM/PCM CONNECTORS
B t25Pl
NOTE (4WD): Do not use the engine to turnthe front wheels with the rear wheels on theground. The 4WD system will engage andthe vehicle will suddenly lurch forward.
Wire side of female terminals
- The MIL ha3 been reDoned on.- DTC P0500" or P0501*1 i33torod.
Probl6m verification:1. Test-drive the vehicle.2. Check the vehicle speed withthe scan tool,
Intermittont failu.e, svstem is OKat thk time. Check for poor con-nection! or loose wiros at C129lvss) .nd ar the EcM/PcM.
ls the correct speed indicated?
Check for rn open in the ECM/PCM:l Turn the ignition switch OFF.2. Elock the rear wheels and setthe parking brake.3. Jack up the front oI the vehicleand support it with satetystands.4. Turn the ignition switch ON {ll}.5. Block the right front whoel andslowly rotate the lett front
6. Measure voltage betweenECM/PCM connector termi-nals 820 and C23.
Substitute a known-good ECM/PCM and rochock. ll symptom/indicetion 9063 away, .oplace th€origin.l ECM/PCM.
Does the voltage pulse between0 V and 5 V or battery voltage?
Check for a short in the ECM/PCMI1. Turn the ignition switch OFF.2. Disconnect ECM/PCM connector C 131P).3. Turn the ignition swilch ON {ll).4. Block the right front wheeland slowly rotate the left front
5. Moasure voltage between ECM/PCM connector terminals 820and C23.
Sub.titute a known-good ECM/PCM and rschock. It rymptom/indication goos .w.y. replecerhe original ECM/PCM.
Does the voltage pulse betlveen0 V and 5 V or battery voltage?
- R.pair short in the wirobetwe€n the ECM/PCM lC23).nd tho VSS.- Roprir open in th6 wirebotweon the ECM/PCM lc23land th6 vss.- It wirc is OK, te3t ihe VSS(!€e soetion 23).
B (25P)
1
*2:Mft
1-136
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PGM-FI System
Grankshaft Speed Fluctuation (CKF) Sensor
fF13361l Tj":""l.tool indicates Diagnostic Trouble Code (DTCI P1336: Intermittent interruption inthe Crankshaft Speed: Fluctuation (CKF) sensor circuit.
The scan tool indicates Diagnostic Trouble Code (DTC) P1337: No signal in the Crankshaft Speed Fluctuation (CKF)
sensor circuit.
Description
The diagnostic system has a pulser rotor on the crankshaft and a pulse pick-up sensor on the engine block. The ECM/PCM
monitors the crankshaft speed fluctuation based on the CKF sensor signal, and judges that an engine misfire occurred if
the fluctuation goes beyond a predetermined limit.
37 mod.l:
CKF SENSOR 2P CONNECTOR IClO4I
T:]l-r'r Lll
l1 zLl''''CKF P I lcKF Mtalu/aeot fdJ twxrneor\-7
Terminal side of male terminals
(To page 11-113)
11-142
- Tho MIL ha3 been reported on.- DTC P1336 and/or P1337 arestored.
Problem verificrtion:1. Do the PCM Reset Procedure.2. Start the engine.
Intermittent {ailure, systom is OK.l thia timo. Ch6ck tor poor con-nections or loose wir$ at ClorlICKF sonsorl .nd at tho PCM.
Chock tor an opon in th6 CKF .en'30r:1. Turn the ignition switch OFF.2. Disconnect the CKF sensor 2Pconnector,3, M easure the resistancebetween the CKF sensor 2Pconnector terminals No. 'l andNo.2.
ls there 1.6-3.2 kO?
Check fo. a short in the CKF 3en-sot:Check for continuity betweenbody ground and the CKF sensor2P connector terminals No. 1 andNo.2 individually.
CKF SENSOR
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PGM-FI System
Grankshaft Speed Fluetuation (CKFI Sensor (cont'dl
.98 - 00 modols:
CKF SENSOR 2P CONNECTOR IClO'I
r-:-i-_ltr_- |l1 2ll,,-'CKF P I ICKF MtsLuneotTOl wlrrneo)\7
Terminal side of male terminals
r:l
t! El
.KFP XA"*."talu rneor \:f
f rwxvneor
ECM/PCM CONNECTOR C (31P)
CKF PIBLU/REDI
CKF M(WHT/BEOI
Wi16 side of l6male terminals
1278__l
-lI(o
T
161716't9202122
,/ 2s262728293()3l
M
- The MIL has boon reported on.- DTC P1336 and/or P1337 arestored.
ProblGm verification:1. Do the ECM/PCM Reset Pro-cedure,2. Stan the engine.
Inte.mittant failuro, 3y*om b OKat thb tima. Chack lor ooor con-nections or looso wirea at C10a{CKF sensorl and.t the ECM/PCM,
Chgck forun open in tho CKF son-sori1. Turn the ignition switch OFF.2. Disconnect the CKF sensor 2Pconnector.3. Measure the resistancebetween the CKF sensor 2Pconnector terminals No. 1 andNo.2.
lsthere 1.6 - 3.2 kO?
Check for a short in the CKF sen-
Check lor continuity betweenbody ground and the CKF sensor2P connector terminals No. 1 andNo.2 individually.
Check for an open in the wiresICKF linca):1. Feconnect the CKF sensor 2Pconnector.2. Disconnect ECM/PCM connec-tor C (31P).
3. Measure resistance betweenECM/PCM connector termi'nals C22 and C31.
Repair opon in the wir6 botwoonthe ECM/PCM 1C22, glll lnd th6CKF s6n3or.
ls there 1.6 - 3.2 kO?
(To page 11'1451
11-144
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ldle Control System
System Description
The idle speed of the engjne is controlled by the ldle Air Control (lAC) Valve'
The valve changes the amount of air bypassing into the intake manifold in response to electric current controlled by the
ECM/PCM. When the lAc valve is activated, the valve opens to maintain the proper idle speed.
YEL/ From PGM'FI
BLK TMAIN RELAY
VARIOUSSENSORS
4.
IAC VALVE
INTAKE MANIFOLD
After the engine starts, the IAC valve opens for a certain time. The amount of air is increased to raise the idle speed
about 150 - 300 rpm.
when the cootant temperature ts row, the lAc valve is opened to obtain the proper fast idle speed The amount o{
bvoassed air is thus controlled in relation to the engine coolant temperature
When the idle speed is out o{ specification and the scan tool does not indicate Diagnostic Trouble Code (DTC) P0505
or P1508, check the following items:
. Adjust the idle speed (see page 11-169, 170)
. Air conditioning signal (seepagell-1551
. ALT FR signal (see page 1l-159)
. Starter switch signal (see page 11-16'1)
. A,/T gear position signal (see section 14)
. PSP switch signal (seepagell-162)
. Brake switch signal (see page 11-165)
. Fast idlethermovalve (see page'11 168)
. Hoses and connecttons. IAC valve and its mounting O-rings
lf the above items are normat, suDslitute a known-good IAC valve and readjust the idle speed {see page 11-169, 170)
lf the idle speed still cannot be adjusted to specification (and the scan tool does not indicate DTC P0505 or Pl508)
after IAC valve reolacement, substitute a known-good ECM/PCM and recheck lf symptom goes away' replace the
original ECM/PCM.
11-149
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ldle Control System
ldle Control System
I P0505 | The scan tool indicates Diagnostic T.ouble Code (DTCI PO5O5: ldlecontrol svstem mattunction.
NOTE: lf DTC P1508 is stored at the same time as DTC P0505, troubleshoot DTC P1508 first. then troubleshoot DTC p0505.
Possibls Cause
. IAC valve mechanical malfunction. Throttle body clogged port, improper adlustment. Intake manifold gasket leakaging. Intake air hose loose leakaging. Vacuum hose leakaging
a ECT sensor incorrect output. Throttle Position sensor incorrect output
Troubleshooting Flowchart
The MIL has been reDorted on.DTC P0505 is sto.ed.
Problem verificationi1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator Ian comes on, thenlet it idle.2. With the scan tool, check thelollowing items.- Throttle position should beapprox. 10% with the throt-tle {ully closed.- Engine coolant temperature shorJld be 194 - 205'F(90 - 96"C).lf they are not within thespec., repair the faulty sen-sor circuit.3 Check the engine speed atidle with no-load conditions:headlights, blower fan. reardefogger, radiator lan, and airconditioner are not operaling,
Inte.mittent failure. syltem is OKat this time.ls it 750 {730)* i 50 rpm?
ls il 700 (680)' rpm or less?
{To page 11-151)(To page 1'l-151)
l:'99 - 00 models
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(From page 11-150)
{From page 11-150}
THERMO VALVE(A/T onlyl
Check the IAC valve:Disconnect the 2P connector from
the IAC valve.
Does the engine speed droP
or the engine stall?
Adiust the (basel idl€ speed lseepage 11-169, 1t0). Itihe ba3e idle
speed cannot be adiust€d, clean
the Dorts in the throttle body.
UPPER
Check the tast idle lhermo valve:
1. Turn the ignition switch OFF.
2. Remove the intake air ductfrom the throttle body.3. Start the engine and let it idle.
4. Put your finger on the lowerpon in the throttle body.
Check engine cool.nt level and for
air in the cooling sy3lem. lf OK,
reolace the f.st idle thermo valve.Does the engine speed drop?
Put your Iinger on the uPPer Portin the throttle body.
Check for vacuum leaks, make
sure the throttle valve is com'pletely clo3ed. and repair as nec-Does the engine speed droP?
Adjust the idle spoed lsee Page11-169. 1701. lf the adiustmentdoes not correct lhe problem,
r.olace the IAC valve.
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ldle Control System
ldle Air Control llAC) Valve
The scan tool indicates Diagnostic Trouble Code (DTC) Pl508: A probtem in the ldle Air Controt flAC) varvecircuit.
The IAC Valve changes the amount of air bypassing the throttle body in response to a current signal from the ECM/PCM inorder to maintain the proper idle speed.
37 model;
IAC VALVE 2P CONNECTOR {C132}
,f rcp'# IYEL/BI.(II2f-1-d)
Y
Wir€ side of female terminals
PCM CONNECTOR A I32PI
tacvIBLK/BLU)
From AIR To INTAKECLEANER MANIFOLD
Wire side of female terminals
The MIL has beon .eport€d on.OIC Pl508 is sto.ed.
Problem veiification:1. Do the PCM Reset Procedure.2. Start the engine, and warm itup to normal operating tem-perature.
Inte.mittent failure, systcm b OKat thi3 time. Check tor poo. con-nections or loose wircs at C132(lAC v.lvel and at the PCM.
ls DTC Pl508 indicated?
Check lor an open in the wir6{lGPl lins}:1. Turn the ignition switch OFF.2. Disconnect the IAC valve 2Pconnector.3. Turn the ignition switch ON {ll).4. Measure voltage between bodyground and the IAC valve 2Pconnector term inal No.2.
Repair open in the wire trctwoontha IAC v!lv6 and the PGM-Flmain relly.
Chock for an opan o. short in thowi.e (lACv linel:1. Turn the ignition switch OFFand reconnect the IAC valve2P connector.2. Disconnect the PCM conneclorA (32P).
3. Turn the ignition switch ON {ll).4, Measure voltage betweenbody ground and PCM con-nector terminal A12.
{To page 1l-153)
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ldle Control System
Fast ldle Thermo Valve lA/T)
Description
To prevent erratic running when the engine is warming
up, it is necessary to raise the idle speed. The fast idle
thermo valve is controlled by a thermowax plunger.
When the engine is cold, the engine coolant surround-
ing the thermowax contracts the plunger, allowing addi-
tional air to be bvDassed into the intake manifold so that
the engine idles faster. When the engine reaches operat-
ing temperature. the valve closes, reducing the amount
of air bypassing into the intake manifold.
IDLEADJUSTING
IDLETHERMOVALVE
AIR BYPASS VALVE
11-168
Inspgction
NOTE: The fast idle thermo valve is factory adjusted; it
should not be disassembled.
1. Remove the intake air duct from the throttle body.
2. Start the engine,
3. Put your finger over the lower port in throttle body,
and make sure that there is air flow with the engine
cold (engine coolant temperature below 86"F, 30'C).
lf there is no air flow, replace the fast idle thermo
valve and retest,
O-RINGSReplace.
11.0 kgfl.m, 7.2 lbl.ftl
Start the engine. Hold the engine at 3,000 rpm with no
load (in Park or neutral) until the radiator fan comes
on, then let it idle.
Check that the valve is completely closed. lf the valve
is leaking, the idle speed will drop when you cover the
lower pon. Check the engine coolant level and for air
in the engine cooling system {see section 10). lf the
cooling system is OK, replace the fast idle thermo
valve and recheck.
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ldle Speed Setting
Inspoction/Adiustmont
37 modsl:
NOTE:
. Before setting the idle speed, check the following
items:- The MIL has not been reportsd on.- lgnition timing- Spark plugs
- Air cleaner- PCV system
. lcanada) Pull the parking brake lever up. Stan the
engine, then check that the headlights are off.
1. Start the engine. Hold the engine at 3,000 rpm with
no load (in Park or neutral) until the radiator fan
comes on, then let it idle.
Connect a tachometer or a Honda PGM Tester.
Disconnect the 2P connector from the ldle Air Con-
trol (lAC) valve.
IAC VALVE
lf the engine stalls, restart the engine with the accel-
erator pedal slightly depr6ss6d, Stabilize the rpm at
1,000, then slowly release the pedal until the engine
idles.
Check idling in no-load conditions: hsadlights,
blower fan, rear d€fogger, radiator fan, and air con-
ditioner are not operating.
ldle spood should b.:
{80 t 50 rpm {in Park or noutr.ll
IDLE
7.
Adjust the idle sp6ed,
idle adjusting screw.
if necessary, by turning the
Turn the ignition switch OFF.
Reconnect the 2P connector to the IAC valve, then
remove the BACK UP (RAD|Ol (7.5 Al fuse in the
under-hood fuse/rslav box for 10 seconds to reset
the PCM.
Restart and let the engine idle with no-load condi-
tions for one minute, then check the idle speed.
NOTE: (Canadal Pullthe parking brake lever up. Stan
the engine, then check that the headlights are off.
ldlo Ep€ed rhould be:
75O t 50 rpm (in P.rk or noutr.ll
Let the engine idl6 for one minute with the head-
lights (Low) ON, and check th€ idl€ speed.
ldle lpcod 3hould bo:
750 t 50 ]pm (in Park or nautlal)
Turn the headlights off. Let th€ engine idle for one
minute with the headlights (Low) ON, heater fan
switch at Hl and air conditioner on. then check the idle
sDeeo.
ldl. specd should b6:
7d) 1 50 rpm {in Park or nautral}
lf the idle speed is not within specification, see the
symptom chart on page 11-64. (cont'd)
1 1-169
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