check engine HONDA CR-V 2000 RD1-RD3 / 1.G Manual Online

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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The MIL has boen r.ported on.DIC Pl 508 b 3tored.
Problem veritication:L Do the ECM/PCM Reset Pro-cedure.2. Start the engine, and warm itup to normal operating tem-perature.
Int€rmittent failure, systom is OKal lhis timo. Check lor poor con-nections or looro wirca at C132(lAc vrlvel and .t rho EcM/PcM.
ls DTC P1508 indicated?
Chock tor an open in the wir6llGPl linel: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 2Pcon nector termina I No, 2.
Repair opon in the wira botwoonthe IAC valve and tho PGM-FImain aalay.
Check tor an open or short in thewire (IACV linel:1. Turn the ignition switch OFFand reconnect the IAC valve2P connector.2. Disconnect ECM/PCM con-nector B {25P).3. Turn the ignition switch ON {ll}.4. Measure voltage betweenbody ground and ECM/PCMconnector terminal 823.
Ropair open or short in thg wirebetween tho ECM/FCM lB23l andthe IAC valve.
ls there battery voltage?
Check the IAC valve func,tion:Momentarily connect ECM/PCMconnector terminals 823 and 82with a jumper wire several times.
Does the IAC valve click?
Subslitute . known-good ECM/PCM .nd rechock. lf symptom/indication goes aw.y, replac.th€ original ECM/PCM.
ldle Air Control (lAC) Valve {cont'd}
'98 - 00 models:
IAC VALVE 2P CONNECTOR {C132I
F rcpt*l tYELrBLxlI2/'-- rf)
Y
Wire side ot fem.le terminals
ECM/PCM CONNECTOR B (25PI
Wire side of female torminals
258
9'to1l13t7
1920212223
tAcv(BLK/BLUIv
PG1{BLKI
12 | t3 4 58
910 111317
1920 | 121)22
tAcv(BLK/
BLU)JUMPER WIRE
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ldle Gontrol System
Air Conditioning Signal (cont'dl
(From page 11-'155)
JUMPERWIRE
UNOER.HOOD FUSE/RELAYBOX 9P CONNECTOR tqt52)
123I
56I
ACC IBLK/RWire side ofACC IBLK/REDIWire side of femaletermrnats
A t32PlPCM CONNECTORS C t3rp)
Wire side ol lemale terminals
Ch6ck for an open in th€ wire(ACC linel:Momentarily connect the under-hood fuse/relay box 9P connectorterminal No.5 to body groundwith a jumper wire several times.
ls there a cl;cking noise fromthe 4!/C compressor clutch?
ls there a clicking noise fromthe 4!/C compressor clutch?See air condiiioner inspection{see section 221.
Repai. op6n in the wire betwoenthe PcM (A17) and tho A/Cclutch relay.
Check the A/C operation:1. Start the engine.2. Turn the blower switch ON.3. Turn the A"/C switch ON.
Check for an open in the wire(ACS line):Measure voltage between PCMconnector terminals Ag and C5.
Does the A,/C operate?
Air conditioning signal is OK.
Repair open in the wire betweenthe PCM lCSl and the A/C awitch.ls there less than 1.0 V?
- Subqtitute a known-good FCM.nd r€ch6ck. lt 3ymptom/indi-cation goes awav, replece theoriginal rcM.- Soe th€ eir conditioner in3pec-tion (s6€ aec.tion 22).
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ldle Control System
Air Gonditioning Signal (cont'd)
JUMPERWIRE
UNDER-HOOD FUSE/RELAYBOX 9P CONNECTOR {G'52I
23a
5589
ACC (BLK/R
Wire side otACC (BLK/RED'
Wire side otfemaleterminals
ECM/PCM CONNECTORS
Wire sid€ of female torminals
(From page '11,157)
Check Ior dn opon in the wiroIACC linel:Momentarily connect the under-hood fuse/relay box 9P connectorterminal No. 5 to body groundwith a jumper wire several times.
ls there a clicking noise lromthe y'y'C compressor clutch?
ls there a clicking noise fromtho A,/C comprossor clutch?Sae rir conditional in3pactionlroa saction 221.
Repai. open in th6 wiro lr€twlanthe ECM/PCM lAl7l .nd tho A/Cclutch rolay.
Check tho op.ration of tho A/C:1. Stan the engine.2. Turn the blower switch ON.3. Turn the Ay'C switch ON.
ChGGk for an open in the wi.eIACS linel:Measure voltage betweon ECM/PCM connector terminals A27and 820.
Does the !y'C operate?
Air conditioning 3ignal i3 OK.
Rap.ir opon in the wir6 bdtunaanrh. Ecil/FcM lA27l rnd rh. A/crwitch.
ls voltage less than 1.0 V?
Sub6lftna a known{ood ECM/PCM and rechock. lf symp-tom/indicetion goes away.roplace the original ECM/rcM.See the ah conditionor inspoc-tion {3e€ section 22},
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Alternator (ALT) FR Signal
This signals the ECM/PCM when the Alternator (ALTI is charging.
,97 modet: PCM GONNECTORS
wire side of female terminals
ALT CONNECTOR (C1O5I
lPr-F- ALT F
lll2llw|{frREDl|3.r-'l-
lruueen wne
c (31P|
wire side ol f€male terminals
PCM CONNECTOR C I31P)
3Pr
JUMPERWIRE
Inspection ot ALT FR Signal.
Check lor a short in the wire
{ALT F line}:1. Disconnect the 4P 13Pi* connector from the ALT.2. Turn the ignition switch ON (ll)
3, Measure voltage betweenPCM connector terminals C17
and A9.Check for a short in the wire(ALT F linel:1. Turn the ignition switch OFF.2. Disconnect the negative bat'tery cable from the battery.3. Disconnect PCM connector C(31P).
4. Check for continuity betweenbody ground and PCM connector terminal C17.
ls there approx. 5 V?
Check th€ ope.ation of the ALT:
1. Turn the ignition switch OFF2. Reconnect the ALT 4P {3Pi*connector to the ALT.3. Start the engine. Hold theengine at 3,000 rpm with no
load (in Park or neutral) untilthe radiator fan comes on,
then let it idle.4. Measure voltage betweenPCM connector terminals C17and A9.
Ropeir short in the wir6 betweonthe PCM lC17l and the ALT.
Substitut. a known-good PCM
and recheck. lf prescribed volt-
age is now availablo, replace the
originalPCM.
Does the voltage decrease when
headlights and rear defogger are
turned on?ALT FR signal b OK.
Ch€d( for an op€n in tho wire IALTF linel:1. Turn the ignition switch OFF.2. Disconnect the negative bat-tery cable lrom the battery.3. Disconnect PCM connector C(31P).
4. Disconnect the 4P (3P)* con-nector lrom the ALT.5. Connect the ALT 4P (3P)* con-nector terminal No. 4 (No. 1)*to body ground with a iumper
6. Check for continuity betweenbody ground and PCN4 con'nector terminal Cl7.
Repair open wi.e between thePCM lCl7l and the ALT.ls there continuity?
ALT F IWHT/REDI
Wire side of female terminals
1 1-159
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ldle Gontrol System
Alternator (ALT) FR Signal (cont'dl
'98 - 00 modols:
ALT CONNECTOR (C1I}5I
4P
rH] Arr Fl'l'ltwHr/REo)l3laF1
I JUMPER WIRE JUMPER+ WIRE
ECM/PCM CONNECTORS
Wire side of female terminals
ECM/PCM CONNECTOR C {31PI
Wire side of female terminals
Wire side of female terminals
ECM/PCM CONNECTOR C {31P}
": Canada
1 1-160
B (25P)
Insp€ction of ALT FR Signsl.
Check fo. a shon in th. wire {ALTF linel:1. Disconn6ct the 4P (3P)* con-nector from the ALT.2. Turn the ignition switch ON {ll).3. Measure voltage between ECM/PCM connector terminals C5and 820.Ch€ck for a sho.t in iho wirc lAlTF lino):1. Turn the ignition switch OFF.2. Disconnecl the negative bat,tery cable from the battery.3. Disconnect ECM,PCM connec-torC (31P).
4. Check for continuity betwoenbody ground and ECM/PCMconnector terminal c5.
ls there approx. 5 V7
Check the opcration of the ALT:1. Turn the ignitioo switch OFF.2. Reconnect rhe ALT 4P (3P)*connector to the ALT.3. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator lan comes on,then let it idle.4. Measure voltage between ECM/PCM connector terminals C5and 820.
Roprir lhort in tho wirc bstweentho ECM/PCM {Csl and the ALT.
Substitut. r known-good ECM/PCM and roch.ck. It Droscrib.dvoltage b now lvrilabls, .eplaccth. o.igin!l ECM/PCM.
Does the voltage decrease whenheadlights and rear defogger areturned on?ALT FR 3ignol is OK,
Chock lor an opon in tha wire (ALTF linel:1. Turn the ignition switch OFF.2. Disconnect the negative bat-tery cable from the battery.3. Disconnect ECM/PCM con-nector C (31P).4. Disconnect the 4P 13P)* con,nector from the ALT.5. Connect the ALT 4P {3P)* con-nector terminal No. 4 1No. 1)*to body ground with a jumper
6. Check for continuity betwe€nbody ground and ECM/PCMconnector terminal C5.
Rsprir opan wiro batw.en thoECM/PCM lcsl .nd th. ALT.ls there continuity?
AI.T F IWHT/REDI
ALT F {WHT/REDI
Wire side ot Iemale terminals
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Starter Switch Signal
This signals the ECM/PCM when the engine is cranking.
'97 model:
A {32P}
'98 - 00 models:
Transmission in E or E position.
LGl(BBN/BLK)
PCM CONNECTORS
Wire side of female terminals
ECM/PCM CONI{ECTORS
STS (BLU/ORNI
c t31P)
NOTE:. M/T: Clutch pedal must be depressed.. A/T: Transmission in E orE position
Check for an opan ot short in the
wire (STS linel:Measure voltage between PCM
connector terminals C6 and Ag
with the ignition switch in the
start (lll) position.
lnspect the No. 31 STARTER SIG-
NAL (7.5 A)Illse in the under'dashls there battery voltage?- Reoair short in the wire be-
tween the PCM lc6l and th.No. 31 STARTER SIGNAL 17 5A) tuse ot the PGM-FI main
reray.- Reolace the No. 31 STARTERSIGNAL t7.5 Altu.e.
Starter swiich signal i3 OK.
Repair opon in the wire betweonrh6 PCM lc6l and the No 31
STARTER SIGNAL 17.5 A)fuse.
A (32P)
Wire side oI female terminals
Check tor an open or short in thewir€ (STS line):Measure voltage between ECM/
PCM connector terminals A24
and 820 with the ignition switchin the start position (lll).
Inspect the No. 31 STARTER SIGNAL (7.5 A){use in the under-dashls there battery voltage?
- Reoair shorl in the wire
betwe€n the ECM/PCM lA2,fland the No, 31 STARTER SIG-NAL t7.5 Al tu3€ ot the PGM'Fl main rclay.- Repl.c. tho No. 31 STARTERSIGNAL 17.5 Al fu3e.
Starter switch 3ignal is OK.
Repair opon in tho wire between
the ECM/PCM {A241 and the No
31 STARTER SIGNAL (7.5 A) tu3e
1 1-161
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ldle Gontrol System
Power Steering Pressure (PSP) Switch Signal
This signals the ECM/PCM when the power steering load is high.
'97 model:
*: Do not hold the steering wheel at tulllock for more than five seconds,
Wire side of female terminals
PSP SWTTCH 2P CONNECTOR 1C135)
PSP SW (GRN)
JUMPER T_7 1 \vnRE t--f r)
GND IBLK}
Wire 3id6 of female terminals
Inspection ot PSP switch signal.
Check for an open in the wire {PSPSYV line):1. Turn the ignition switch ON (ll).2. Measure voltage betweenPCN4 connector terminals C16and A9.
Check tor an open in lhe wire (PSPSW linel:1. Turn the ignition switch OFF.2. Disconnect the PSP switch 2Pconnecror,3. Turn the ignition switch ON (ll).4. At the harness side, connectthe PSP switch 2P connectorterminals No. 1 and No. 2with a jumper wire.5, Measute voltage betweenPCM connector terminals C16and A9.
ls there less than 1.0 V?
- Ropsir open in the wi.e be-twoon the PCM lcl6l and thePSP switch.- Ropdir open in BLK wire be-tween the PSP switch andG101.
ls there less than 1.0 V?Check the operation oI lhe PSPswitch:1. Stan the engine2. Turn the steering wheelto thefull lock position*.
3. Measure voltage between PCMconnector terminals C16 andA9.
ls there battery voltage?
PSP switch signal is OK.(To page 11-163)
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ldle Control System
Power Steering Pressure (PSP) Switch Signal (cont'dl
'98 - 00 models:
*: Do not hold the steering wheel at lulllock for more than five seconds.
ECM/FCM CONNECTORS
PSP SwlTCH 2P CONNECTOR ICl35}
PSP SW IGRNI
JUMpER f-7 T \wtRE L-5 rl
GND (3LX}
Wire side of lemale terminals
Inspection of PSP swilch 3ignal.
Ch€ck tor rn opon in the wire (PSP
SW line):1. Turn the ignition switch ON {ll).2. Measure voltage betlveen ECM/PCM connector terminals 426and 820.
Chock for an open in the wire IPSPSW lin€):1. Turn the ignition switch OFF.2. Disconnect the PSP switch 2Pconnector,3. Turn the ignition switch ON (ll).4. At the wire side. connect thePSP switch 2P connector terminals No. 1 and No.2 with a
5. Measure voltage between ECM/PCM connector terminals 426and 820.
ls there less than 1.0 V?
- Ropai. open in the wire be-tweon th6 ECM/PCM (A26)
and th6 PSP .witch.- R6p.ir open in BLK wire be-tween tho PSP 3witch andG 101,
lsthere less than 1.0 V?Check the op€ration of the PSPswitch:1. Stan the engine2. Turn steering wheel to the fulllock position*.3. Measure voltage b€tween ECM/PCM connector terminals A26and 820.
ls there battery voltage?
PSP switch signal is OK.
Wire side of female terminals
11-164
(To page 11-165)
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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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