1999 HONDA CR-V Idle air

Troubleshooting
Engine/Powertrain Control Module Terminal Arrangement - '98 - 00 Models
(cont'd)
ECM/PCM CONNECTOR B {25PI
Wire side of female terminalsECM/PCM CONNECTOR B I25PI
*2t MlT*3: '98 model"4: '99 - 00 models
NOTE: Standard baftery voltage is l2
Ierminalnumb€tWire colorTerminsl nameDescriptionSignal
1YEUBLKIGPl (POWER SOURCE)Power source for the ECM/PClvlcontrol circuit.withagewith
ignition switch ON (ll): battery volt-
ignition switch OFF:0 V
BLKPG1 (POWER GROUND}Ground for the ECM/PClvl controlcircuit.Less than 1.0 V at all times
REDlNJ2 (No. 2 FUEL INJEC-roR)Drives No. 2 Iuel injector.With engine running: duty controlled
BLUlNJ3 1No. 3 FUEL INJEC-TOR)Drives No. 3Iuel jnjector.
YELlNJ4 {No.4 FUEL INJEC-TOR)Drives No. 4 fuel injector.
8*1WHTLS- (A"/T CLUTCH PRES.SURE CONTROL SOLE,NOID VALVE _ SIDE)
A,/T clutch pressure controlsolenoid valve power supplynegative terminal.
With ignition switch ON (ll): dutycontrolled
9YEUBLKIGP2 IPOWER SOURCE)Power source for the ECN,I/PCMcontrol circuit.With ignition switch ON (lll: bafteryvoltageWith ignition switch OFF:0 V
10BLKPG2 (POWER GROUND}Ground for the ECM/PCM controlcrrcurt.Less than '1.0 V at all times
' BRNlNJl (No. 1 FUEL INJECTOR)Drives No. l tuel injector.With engine running: duty controlled
YEUGRNrcM {rGNrTroN coN-TROL MODULE)Sends ignition pulse.With ignition switch ON (ll): batteryvoltageWith engine running: pulses
17*1REDLS+ (A,,IT CLUTCH PRESSURE CONTROL SOLE-NOID VALVE + SIDE)
A,/T clutch pressure controlsolenoid valve power supplypositive terminal
With ignition switch ON (ll): dutycontrolled
19*.PNK
ODIND (OVER-DRIVE
OFF INDICATOR}Drives OVER-DRIVE OFFindicator light.With OVER-DRIVE OFF indicator lightturned ON: 0 VWith OVER-DRIVE OFF indicator lightturned OFF: battery voltage
20BRN/BLKLG1 (LOGIC GROUND)Ground for the ECM/PCM controlcircuit.Less than 1.0 V at all times
WHT/BLUVBU (VOLTAGE BACKUP)Power source for the ECM/PCMcontrol circuit.Power source forthe DTC memory.
Battery voltage at all times
22BRN/BLKLG2 (LOGIC GROUND)Ground for the ECN4/PCM controlctrcutt,Less than 1.0 V at all times
23BLVBLUIACV {IDLE AIR CON.TROL VALVE)Drives IAC valve.With engine running: duty controlled
11-72
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ECM/PCM CONNECTOF C (31PI
Wire side o{ female terminal€ECM/PCM CONNECTOR C (31P)NOTE: Standard battery voltage is 12 V.
TermidalD.3criptionSignal
8LI(WHTPOzSHTC {PRIII4ABY HEATEDOXYGEN SENSOR HEATERCONTROL)
Drivss prim6ry h$ted oxygsn sensorWilh ignition switch ON (ll): baneryvoltsgeWith ftrllywarmsd up €ngine runnang: duty
2"WHT/GBNALTC (ALTERNATOR CON,TROL)Sonds alternalor control signsl.With fully wafmod up €ngine rnningr ban€ryvoltagoDu ng driving with small elsctrical lo6d: 0 v
3'1FED/8LUKS (KNOCK SENSOR)Dstects KS signal.With engine knockang: pulses
5WHT/REDALTF (ALTERNATOR FR SIG-NAL}Detects alternator FR signal.Wth fullywarmed up €ngine running:0 V-batteryvoltag€ {d€pending on slsctrical load)
1GRN,4trHTSG1 (SENSOR 680UND}Ground for l/tAP sensor.L€ss than 1.0 v 6t all times
8BLUCKPP (CKP SENSOF P SIDE)Dat€cls CKP s6nsor.With €ngin€ runningr puls€s
9CKPI.,I| {CKP SENSOF M SIDE)Ground for CKP s€nsor.
15PHO2S {PRIMARY HEATEDOXYGEN SENSOR, SENSOR 1)Detocts pfimary he6t6d oxygen ssnsor
{sonsor 1)signal.with ihfottls fully opened from idle with fully,
walm6d up engins: above 0.6 VWith throttlo quickly clossd: below 0.4 v
17RED/GRNMAP (MANIFOLD ABSOLUTEPRESSURE SENSOR)
D6tects MAP s€nsor sign6l.With ignition switch ON (ll):about 3 VAt idls: aboul 1.0 V {dspsnding on engine speed)
18GRN/BLKSG2 (SENSOB GNOUNDiLsss than 1.0 V at all tim€s
19YEUBEDVCCl {SENSOR VOLTAGE)Power soufce to MAP s€nsor.With ignition switch ON (ll): about 5 VWith ignition switch OFF:0 V
20GRNTDCP {TDC SENSOR P SIDE)Derecis TDC sensor.With engine funning: Pulses
2lREDTDCM ITDC SENSOR M SID€)Ground for TDC sensor.
22BLU/REDCKFP (CKF SENSOR PSIDE)Dstscts CKF s€nsor.With sngins running: pulsss
23BLU/WHTVSS (VEHICLE SPEED SEN-soR)Dstscrs vss signal.With ignition switch ON (ll)and front wheelsrotaringrcyclss 0 v- 6bout 5 V or ban€ry voltage
25RED//ELIAT (INTAKE AIR TEMPERA'TURE SENSOB)Detacts IAT sensor signal.With igniiion switch ON (ll): about 0.1 - 4.8 V(d€p€nding on iniate air t€mp€raturc)
26REO/WHTECT {ENCINE COOLANTTEMPERATURE SENSOR)oetscts ECT sensor signal.With ignition switch ON (ll): about 0.1 4.8 V
{doponding on 6ngin€ coolanl lemper6tu16)
27RED/BLKTPS (THROTTLE POSITIONSENSOR)Dotects TP sensor signrl.with rhrottls fully op€n: aboui 4.8 vwith throtrl6 fullyclosed: about 0.5 v
2AYEUBLUVCC2lSENSOR VOLTAG€}Provid€s s€nsor voltage.With ignilion switch ON (ll): about 5 VWhh ignition switch OFF: 0 V
29YELCYPP ICYP SENSO8 P SIDE)Dsrscts CYP sensor.With €ngins runningr pulsss
30BLKCYPM (CYP SENSOR M SIDE)Ground for CYP sansor.
31WHT/REDCKFM {CKF SENSOR M SIDE)6.ound lof CKF ssnsor signal.
11. AfT 13. '94 model'2:M/T 14:'99- 0o modsls.5: USA
(cont'd)
11-73
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PGM-FI System
System Description
INPUTS
CKP/TDC/CYP Sensor
CKF Sensor
MAP Sensor
ECT Sensor
IAT Sensor
TP Sensor
Primary HO2S
Secondary H02S
vss
KS*5
BARO Sensor
ELD*6
Starter Signal
ALT FR Signal
Air Conditioning Signal
Ay'T Gear Position Signal*1
Baftery Voltage (lGN.1)
Brake Switch Signal
PSP Switch Signal
Fuel Tank Pressuae Sensor*4. *5
Countershaft Speed Sensor*1
Mainshaft Speed Sensor*r
OVER-DRIVE Switch Signal*s
ENGINE CONTROL MODULE (ECM)/
POWERTRAIN CONTROL MODULE (PCM) OUTPUTS
|iuel 1"j""- Th,rhg ""d Drrafr";-l
Et*-.nt"tdt"cont.orl
to,r*,c;;trffi;]
l.----.---:. .Lrgnrnon |lmrng Lonrror I
Ecir/PcM B*k',p Fr""il]
m;"t-ll-r*'io*l
Fuel Injectors
PGM-Fl Main Relay (Fuel Pump)
MIL
IAC Valve
Ay'C Compressor Clutch Relay
Radiator Fan Relay
Condenser Fan Relay
ALT
tcM
EVAP Purge Control Solenoid
Valve
Primary HO2S Heater
Secondary H02S HeaterEVAP Bypass Solenoid Valve*a *5
EVAP Control Canister Vent Shut
DLC
Lock-up Control Solenoid Valve*l
Shift Control Solenoid Valve*1
Ay'T Clutch Pressure Control
Solenoid Valve*1
D4 Indicator Light'1 *3, *a
D Indicator Light,l *5
OVER-DRIVE OFF Indicator
Lighl*t *:
*1: A/T {3:'97 model'2: M/f +4:'98 model*5: '99 - 00 models"6: USA
PGM-Fl System
The PGM-Fl system on this model is a sequential multiport fuel injection system.
Fuel iniecior Timing and Duration
The ECM/PCM contains memories for the basic discharge durations at various engine speeds and manifold pressure. The
basic discharge duration, after being read out from the memory, is further modified by signals sent from various sensors
to obtain the final discharge duration.
ldle Air Control
ldle Air Control Valve (lAC Valve)
When the engine is cold, the Ay'C compressor is on, the transmission is in gear, the brake pedal is depressed, the P/S load
is high, or the alternator is charging, the ECM/PCM controls current to the IAC Valve to maintain the correct idle speed.
lgnition Timing Control
o The ECM/PCM contains memories for basic ionition timing at various engine speeds and manifold air flow rates.
lgnition timing is also adjusted for engine coolant temperature.
. A knock control system was adopted which sets the ideal ig nition timing for the octane rating of the gasoline used.*s
Other Control Funstions
1. Starting Control
When the engine is started. the ECM/PCM provides a rich mixture by increasing fuel injector duration.
2. Fuel Pump Control
. When the ignition switch is initially turned on (ll). the ECMiPCM suppli€s ground to the PGM-FI main relay that
supplies current to the fuel pump for two seconds to pressurize the fuel system.
. When the engine is running, the ECM/PCM supplies ground to the PGM-FI main relay that supplies current to the
fuel oumo.
. When the engine is not running and the ignition is on, the ECM/PCM cuts ground to the PGM-FI main relay which
cuts current to the fuel pump.
1 1-80
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Fuel Cut-off Control
. During deceleration with the throttle valve closed, current to the fuel injectors iscutoffto improvefuel economyat
speeds over 970 rpm ('97 - 98 models), 920 rpm ('99 - 00 modelsl.
. Fuel cut-off action also takes place when engine speed exceeds 6,500 rpm ('97 - 98 models), 6900 rpm ('99 - 00
models), regardless of the position of the throttle valve, to protect the engine from over-rewing.
With Ay'T model. the PCM cuts the fuel at engine speeds over 5,000 rpm when the vehicle is not moving.*'
4,./C Comoressor Clutch Relav
When the ECM/PCM receives a demand for cooling from the air conditioning system, it delays the compressor from
being energized, and enriches the mixture to assure a smooth transition to the Ay'C mode.
Evaporative Emission (EVAP) Purge Control Solenoid Valve
When the engine coolant temperature is above 154"F (68'C), the ECM/PCM controls the EVAP purge control solenoid
valve which controls vacuum to the EVAP purge control canister,
Alternator Control
The system controls the voltage generated at the alternator in accordance with the electrical load and driving mode.
which reduces the engine load to improve the fuel economy.
PCM Fail-saf e/Back-up Functions
1. Fail-safe Function
When an abnormality occurs in a signal from a sensor, the ECM/PCM ignores that signal and assumes a pre-pre
grammed value for that sensor that allows the engine to continue to run.
2. Back-up Function
When an abnormality occurs in the ECM/PCM itself, the fuel injectors are controlled by a back-up circuit independent
of the system in order to permit minimal driving.
3. Self-diagnosis Function IMalfunction Indicator Lamp (MlL)l
When an abnormality occurs in a signal from a sensor, the ECM/PCM supplies ground for the MIL and stores the DTC
in erasable memory. When the ignition is initially turned on {ll), the ECM/PCM supplies ground for the MIL for two
seconds to check the MIL bulb condition.
4. Two Trio Detection Method
To prevent false indications, the Two Trip Detection Method is used for the HO2S*1, fuel metering-related. idle control
system, ECT sensor and EVAP control system self-diagnostic functions. When an abnormality occurs, the ECM/PCM
stores it in its memory. When the same abnormality recurs after the ignition switch is turned OFF and ON (ll) again,
the ECM/PCM informs the driver by lighting the MlL. However, to ease troubleshooting, this function is cancelled
when you jump the service check connector, The MIL will then blink immediately when an abnormality occurs.
5. Two (or Three) Driving Cycle Detection Method {'97 model)
A "Driving Cycle" consists of starting the engine, beginning closed loop operation, and stopping the engine. lf misfir-
ing that increases emissions or EVAP control system malfunction is detected during two consecutive driving cycles.
or TWC deterioration is detected during three consecutive driving cycles, the ECM/PCM turns the MIL on. However, to
ease troubleshooting, this function is cancelled when you jump the service check connector. The MIL will then blink
immediately when an abnormality occurs.
*1: '97 - 98 models*2: '99 - 00 models
5.
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PGM-FI System
Manifold Absolute Pressure (MAP) Sensor (cont'd)
[tn,t nn-] The scan tool indicates Diagnostic Trouble Code (DTC) P0108: A high voltage (low vacuum) problem in the|jg Manifold Absolute Pressure (MAP) sensor.
MAP SENSOR 3P CONNECTOR IC131I
Wire side of female terminals
vcclIYEL/RED}
PCM CONNECTOR D I16PI
JUMPER WIRE
sGlIGRN/WHTI
Wire side of lemale termin6ls
1
(To page 11,93)': '98 - 00 models
1-92
tcRN/wHrll IIRED/GRN|
The MIL has boen reported on.DTC m108 is slored.
Problem veritication:1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on, thenlet it idle.2. Check the MAP with the scantool.
Intermittent tailuro, system i3 OKat this time. Check tor ooor con-nections or loose wires at C131IMAP s6nsor) snd the ECM/rcM.
ls 101 kPa {760 mmHg,30 in.Hg),2.9 V or higher indicated?
Check Ior an open in the MAPsensor:1. Turn the ignition switch OFF.2. Disconnect the MAP sensor3P connector.3. lnstall a jumper wire betweenthe MAP sensor 3P connectorterminals No.3 and No.2.4. Turn the ignition switch ON {ll).5. Check the MAP with the scantool.
ls 10'l kPa (760 mmHg,30 in.Hg),2.9 V or higher indicated?
Check for an open in wire (SGlliDel:1. Remove the jumper wire.2. Measure voltage between theMAP sensor 3P connector ter-minals No. 1 and No- 2.
R6p.ir open in the wire betwoenthe ECM/PCM (D12, CTrl and theMAP sensor.
ls there approx. 5 V?
Check for an open in the wire(MAP line):1. Turn the ignition switch OFF.2. lnstall a iumper wire on thePCM connectors between D3and D12.3. Turn the ignition switch ON (ll).4. Check the MAP wirh the scantool.
Ropair opon in the wire betweenthe PCM {D3, .nd the MAP son-3('t.
ls 101 kPa 1760 mmHg, 30 in.Hg),2.9 V or higher indicated?
YES
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{From page 11-110}
Check tor a shorl in the HO2S:1. Turn the ignition switch OFF.2. Disconnect the Primary HO2S(Sensor'1i 4P connector.3. Start the engine and let it idle.4. Check the Primary HO2S(Sensor 1)output voltage withthe scan tool.
Replace the HO2S {Sensor 1).Does it stay at 0.1 V or less?
Check for a short in the wir€(PH02S linel:1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector (D (16P), C (31P)*).
3. Check tor continuity betweenthe Primary HO2S {Sensor 1)4P connector terminal No. 1and body ground.
Repair short in tho wire botwesnthe ECM/PCM lD7, C16*) .nd th6Prim.ry HO2S (S€nsor 11.
Substituto a known-good ECM/PCM and recheck. ll 3ympiom/indication goes away. raplace th.origin.l ECM/PCM.
PRIMARY HO2S ls.n.or 'l I 4P CONNECTOR (Cl111
PHO2S ---'trwHTr T-T-l
T-1 1 2l
6tlr rlY r___J_J
L
Wire side of temale terminals
(cont'd)
11-111
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PGM-FI System
Knock Sensor {KSl
('99 - 00 models) The scan tool indicates Diagnostic Troublo Code (DTC) P0325: A malfunction in the circuit ofthe Knock Sensor (KS).
ECM/PCM CONNECTOR C 131P}
Wire side of female terminals
KS 1P CONNECTOR IC13?'
KSIRED/BLU)
KS(BED/BLU)
Wire side ol femaletermtnals
ECM/PCM CONNECTORc (31P)
- The MIL has been rooorted on.- DTC m325 is storod.
Problem verification:1. Do the ECM/PCir, Reset Procedure,2. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator tan comes on,then let it idle.3. Hold the engine at 3,000 -
4,000 rpm for at least 60 sec-onds,
Intermittent lailu.e, 3ystom is OKat thi3 tim. (te3t drive m.y benacalLrYr.Chock to. poor connsctions olloora wiros rt C137 lknock aon-.o. (KS)) and ar the ECM/FCM.
Ch€ck tor a short in the wir6 {KSlinel:1. Turn the ignition switch OFF.2, Disconnect the knock sensorlP connector.3. Check lor continuity betweenECM/PCM connector terminals C3 and body ground.
Replil rhort in the n irg b6{wocntho ECM/PCM lc:ll and the knocks€ngr1.
Check fo..n open in the wire{KS line):Check for continuity betweenECM/PCM connector terminal C3and knock sensor connector ter,minal No. 1.
B.pair opon in the wirc lrotweenlho ECM/PCM lctl and thc knockacnsor.
ls there cont;nuity?
Substitute a known-good knocksensor and recheck.
ls DTC P0325 indicated?Bcpl.ce the original knock 3€nsor,
Substituto a known-good ECM/PCM and .echeck. lf 3ymptom/indication goes away, replacethe original ECM/PCM.
NOTE: Torque the knock s6nsor to31 N.m (3.2 kgl.m, 23 lbf.ft).
1 1-130
Wire side ot female terminals
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PGM-FI System
Electrical Load Detestor (ELDI (USA Model) (cont'dl
The scan tool indicates Diagnostic Trouble Code {DTC) Pl298; A high voltage problem in the Electrical Load
Detector (ELD) circuit.
97 modsl:
ELD 3P CONNECTOR {C35,'I
Wire sido oI lemale terminals
r lzlrl--T_ow
/6 IBLKI
Y
Repail op€n in th. wire b€tws€ntho No. 15 ALTERNATOR SPSENSOR 17.5 A) tuse in theunder-dlrh fuso/r.lay box andth6 ELD.EL {GRN/NEDI
PCM CONNECTORS
Problam verification:1. Do the PCM Reset Procedure.2. Start the engine.3. Turn on the headlights.Intermittent tailuro, systcm is OK.t this time. Chack for ooor con-noction! or looro wire3 at C127{locaied on PCM brackot), C35{{ELDI and .t tho PCM.
Chack for an opan in tho wilellGl linol:1. Turn thg ignition and head-lights OFF.2. Disconnect the ELD 3P connector.3. Turn the ignition switch ON {ll).4. M6asure voltage b€tw€enbody ground and the ELD 3Pconnoctor terminal No. 1.
Chock lol !n open in the wireIGND linel:'1. Turn the ignition switch andheadlights OFF.2. Disconnect the ELD 3P conneqor,3. Check for continuity betweenbody ground and the ELD 3Pconnector terminal No. 2.
Ropair opon in th6 wi.e betweonth. ELD connector rnd GiO2,
Ch.ck lo. an open in th€ wiro (EL
line):Check for continuity between theELD 3P connector terminal No. 3and PCM connector terminal 016.
Chock for . malfunction in theELD:1. Reconnect the ELD 3P con-neclor,2. Start the engine and allow itto idle.3. While measuring voltagebetween PCM connector terminals 016 and A9. turn theheadlights on (low).
ls there continuityT
R6pafu op6n in tho wire betweenthe PCM {D161snd th6 ELD.
Subltituto . known-good PCMand rachock, f symptom/indic.-tion goes awry, ropl.ce the origi-n.l PCM.
Does the voltage drop?
Wire side of lemale terminals
11-140
Wire side of lemale terminals
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