fuel HONDA CR-V 1998 RD1-RD3 / 1.G Repair Manual

Powertrain Control Module Terminal Arrangement -'97 Model
FCM CONNECTOR A (32P)NOTE: Standard battery voltage is 12 V.
Wire side of lemale terminals
f€rminalnumlreJWirecolor
Telminalnama
DescriptionSignal
YELlNJ4 (No.4 FUELINJECTOR)Drives No. 4 {uel injector.With engine running: duty controlled
2BLUlNJ3 (No.3 FUELINJECTOR)Drives No. 3luel injector.
REDlNJ2 {No.2 FUELINJECTOR)Drives No.2 tuel injector.
BRNlNJl (No. l FUELINJECTOR)Drives No. 1 fuel injector.
5BLK WHTSO2SHIC (SECONDARY
HEATED OXYGEN SENSOR HEATER CONTROL)
D ves secondary heated oxygensensor heater.With ignition switch ON {ll): battery voltageWith fully warmed up engino running: dutycontrolled
6BLKAr'YHT
PO2SHTC (PRIMARY
HEATED OXYGENSENSOR HEATERCONTROL}
Drives primary heated oxygensensor heater,With ignition switch ON lll): battery voltagewith fully warmed up engine running: dutycontroll6d
I8RN/BLKLGl (LOGIC GROUND}Ground forthe PCM control circuit.Less than 1.0 V at all times
10BLKPG1 lPOWER GROUND}Ground for the PCM power circuit.
l1YEUELKIGPl lPOWER SOURCE}Power source for the PCM controlcircuit.
With ignition switch ON (ll): battery voltageWith ignition switch OFF: 0 V
12BLI(BLUIACV {IDLE AIRCONTROL VALVE}Drives IACV.With €ngine running: duty controlled
REDryEL
PCS (EVAP PURGECONTFOL SOLENOIDVALVE)
Drives EVAP purge controlsolenoid valve.
With engine running, engine coolantbelow 154'F (68"C): battery voltageWith engine running, engine coolantabove 154"F (68"C): duty controlled
16GRN/VELFLR (FUEL PUMP RELAY)Drives Iuel pump relay.0 V for two seconds after turning ignition
switch ON lll), then battery voltage
118LI(REDACC (A,/C CLUTCHRELAY}Drives Ay'C clutch relay.With comoressor ON: 0 VWith compressor OFF: baftery voltage
18GRN/ORNMIL (MALFUNCTION
INDICATOR LAMP}Drives MlL.With MIL turned ON: 0 VWith MIL turned OFF: baftery voltage
19*WHT/GRNALTC (ALTERNATOR
CONTROL}Sends alternator control signal.With tully warmed-up engine running:
battery voltageDuring driving with smallelectrical load:0 '
20YEUGRNICM (IGNITION CONTROLMODULE)Sends ignition pulse.With ignition switch ON (ll): baftery voltageWith engine running: pulses
22BRN/BLKLG2 (LOGIC GROUND}Ground tor the PCM control circuit.Less than 1.0 V at alltimes
23BLKPG2 {POWER GROUND}Ground lor the PCM power circuit.
24YEUBLKIGP2 {POWER SOURCE}Power source for the PCM controlcircuit.
With ignition switch ON (ll): battery voltage
With engine switch OFF: 0 V
27GRNFANC (RADIATOR FANCONTROL)Drives radiator {an relay.With radiator fan running: 0 VWith radiator fan stopped: baftery voltage
*: USA
{cont'd)
11-67
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Engine/Powertrain Control Module Terminal Arrangement - 38 - 00 Models
ECM/PCM CONNECTOR A (32P}
,/./5aIsca
,/ l,/t5ItsTs
n2ls!uCI
Wire side ot female terminalsECM/FCM CONNECTOR A {32P)NOTE: Standard baftery voltage is '12 V.
D93criptionSignal
3BLU2WBS {EVAP BYPASSSOLENOID VALVE)Drives EVAP bvoass solonoid valve.With ignirion switch ON {ll)r battery voltage
LT GRNMHTVSV {EVAP CONTROL CANISTEB VENT SHUT VALVE)D.ives EVAP controlcanisler vent shutWith ig^ition switch ON (ll): battery voltage
5',BLUCRS (CRUISE CONTROL SIG'NAL)Shift Oown signalinputfrcm cruise conWhen cruise control is used: pulses
6RED/YEL
PCS (EVAP PURGE CONTROLSOLENOID VALVE)Drives EVAP purge controlsolonoid valve.With engins running, engine coolant, below 154'F(68'C)r battery voltageWith engine running, engine coolant, above 154"F{6a'C}r duty conl.olled
8ELIOWHTSO2SHTC (SECONDARVHEATED OXYGEN SENSORHEATER CONTROL)
Drives sacondary heated oxygen sensorWith ignition switch ON (ll): banery voltageWith fully warmed up engine running: duty
10BRNSCS (SERVICE CHECX SIGNAL)Detects seNics check conneclor signal(he signalcausing a DTC indicatjon)with rhe lerminal connected:0 vWith the rerminaldisconnectedrabout 5 v or
l4'rGRN/8LKD4IND (D4INDICATOR)+3DIND (D INDICATORTIDrives D4*3. Dr'indicaior light.W,rh 04' , O" indrcator light turned O batter,
With D4*3, D*. indicator light turned OFFr0 V
16GRNI/ELFLR (FUEL PUMP RELAY)Drivss fusl pump relay.0 V for iwo seconds after ru'nin9 ign'lion swilchON lll), then banery voltage
17AL|(/REDACC (I/C CLUTCH RELAY}Drives l,/C clurch rclay.With compressor ONr0 VWith compressor OFF: battery voltage
18GRN/ORNMIL (MALFUNCTION INDICA.TOR LIGHT)Driv€s MlL.With MlLturned ON:0 VWith MIL turned OFF: battery voltage
19BLUNEP (ENGINE SPEED PULSE)Outputs engine spsed pulse.With sngine runnin9: pulses
20GRNFANC {RADIATOR FAN CONTROL)Drives r6diator fan rslay.With radaator fan running:0 VWith radaatorfan stopped: battery vollage
218LU/t/ELK-LINESends and receiv€s scan toolsignal.With ignition switch ON (ll): p'rlses
23WHT/REDSHO2S (SECONDARY HEATEDOXYGEN SENSOR. SENSOR 2iDetects secondary h€at€d oxygen sensorWith throttle fully opened from idle wilh fullywalmed up engine: above 0.6 Vwith rhrottle quickly closed: below 0-4 V
21BLU/WHTSTS (STARTER SWITCH SIG,NAL}Dotocts srarter switch signal.Whh staner switch ON (lll): batlery voltageWith srarter switch OFF: 0 V
26GBNPSPSW {P/S PsESSUFESWITCH SIGNAL)Detecrs PSP switch signal.At idle with steeing wh€el in stBighl ahead position: 0 VAt idls with nee ng wheel al full lockr banory voltage
2fBLU/BEOACS (Ir'C SWTCH SIGNAL}D€tects ly'C switch signal.With Ay'C switch ON:0 VWith l/C swil€h OFF: about 5 V
2A'\WHT/NEDSLU {INTERLOCK CONTROLUNIT)Orives interlock control unil.With ignilion switch ON (ll)and brake pedaldepressed: battery vohage
29LT GRNPTANK (FUEL TANK PRES'SURE SENSOR)Detocts fueltank pressure sensor signal.With agnition switch ON (ll) and fuel fill capopensd; about 2.5 v
GBN/FEDEL (ELD}Detects ELD signal.Wirh paaing rightstumed on at idle:about 2.5 - 3.5 VWith low beam headlights tumed on at idle:about 1.5-2.5V
GRN/WHTBKSW (BRAKE SWTTCH)Dst€cts brake switch signal.Wirh brake pedal released:0 VWith brake pedal depressed: battery vollage
13: '98 modsl
15: USA(cont'd)
11-71
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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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Diagnostic Trouble Code (DTCI Chart
*: These DTCS will be indicated by the blinking of the Malfunction Indicator Lamp (MlL) with the SCS service connector
connected.**: The E (E)*u indicator tight and the Malfunction Indicator Lamp (MlL) may come on simultaneously.*1' AIT *3 '97 model +5; '99 - 00 models*2: MlT *4:'98 model
{cont'd)
11-75
DTC(MlL indication*lDetection ltemProbable CausePago
P0107 (3)Manifold Absolute
Pressu.e CircuitLow Input
Open or short in MAP sensor circuit
MAP sensor
ECMiPCM
't 'l-90
P0108 {3)
Manifold AbsolutePressure Circuit
High Input
Open in MAP sensor circuitMAP sensor
ECM/PCM
11-92
P01 1 1*3 (10)Intake Air
Temperature Circuit
Range/Performance Problem
. IAT sensor
11-95
P0112 (10)lntake Air
Temperature CircuitLow Input
Short in IAT sensor circuit
IAT sensorECM/PCM1 1-96
P0113 (10)lntake Air
Temperature Circuit
High lnput
Open in IAT sensor circuit
IAT sensor
ECM/PCM
'I 1-97
P0116 (86)Engine CoolantTemperature CircuitRange/Performance Problem
ECT sensor
Cooling system1 1-99
P0117 (6)Engine Coolant
Temperature Circuit
Low Input
Short in ECT sensor circuit
ECT sensor
ECM/PCM
1 1-100
P0118 (6)Engine Coolant
Temperature CircuitHigh Input
Open in ECT sensor circujt
ECT sensor
ECM/PCM
11-101
P0122 \11
Throttle Position
Circuit
Low Input
Open or short in TP sensor circuitTP sensor
ECM/PCM
11-103
P0123 l7l
Throftle Position
Circuit
High Input
Open in TP sensor circuit
TP sensor
ECM/PCM11-107
P0131 (1)
Primary Heated Oxygen Sensor
Circuit Low Voltage(Sensor 1)
Short in Primary HO2S {Sensor 1)
circuit
Primary HO2S (Sensor 1)
Fuel supply system
ECM/PCM
1 1-1 10
P0132 (1)Primary Heated Orygen SensorCircuit High Voltage(Sensor 1)
Open in Primary HO2S (Sensor 1) circuitPrimary HO25 (Sensor 1)ECM/PCM
'11113
P0133 (61)Primary Heated Oxygen Sensor
Slow Response(Sensor 1)
. Primary HO2S (Sensor 1). Exhaust system11'I 16
P0135 (41)
Primary Heated Oxygen SensorHeater
Circuit Malfunction
{Sensor 1)
. Open or short in Primary HO2S (Sensor'l) heater circuit. ECM/PCM11-12'l
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Troubleshooting
Diagnostic Trouble Code (DTCI Chart (cont'd)
*: These DTCS will be indicated by the blinking o{ the Malfunction Indicator Lamp (MlL) with the SCS service connector
connected.**: The E (El*s indicator light and the Malfunction Indicator Lamp {MlL) may come on simultaneously,*1; A/T *3: '97 model *5: '99 - 00 models*2: MlT *4: '98 model
11-76
DTClMlL indicationlDetection hemProbable Caus.Page
P0137(63)Secondary Heated Oxygen SensorCircuit Low Voltage{Sensor 2)
Shon in Secondary HO2S (Sensor 2) circuatSecondary HO2S (Sensor 2)ECM/PCM
'n-1t7
P0138 (63)Secondary Heated Oxygen SensorCircuit High VoltageOpen in Secondary HO2S (Sensor 2) circuitSecondary HO2S (Sensor 2)EC|\il/PCM11118
P0139{63)Secondary Heated Oxygen Sensor
lSensor 2i
Secondary HO2S (Sensor 2)11-120
P0141 (65)Second6ry Heated Oxygen Sensor HeaterCircuit Malfunction(Sensor 2)
Open orshon in Secondary HO2S (Sensor 2)heater circuitEC|V/PCtu11't2l
P0r71 (45)
System Too LeanFuel supply systemPrimary HOzS (Sensor 1)
Contaminated fuel
Exhaust leakage
11124
P0112 (45)
System Too RichFuel supplv systemPrimary HO2S (Sensor 1)
Contaminated fuel11 124
and
Po3ol ltr \P0302 112 |P0303 173 iP0304 \74 t
Random Mistirelgnition systemFuel supply system
IAC valveContaminated fuelLack of fuel
11-126
P0301 /71 \P0302 112 |P0303 173 |P0304 \7 4l
- Cylinder 1- Cylinder 2Cylinder 3- Cylinder 4Misfire Detected
Fuel injectorFuel injector circuitlgnition system't't 127
P0325*5{23)Knock Sensor {KS) Circuit MalfunctionOpen or shon in Knock Sensor (KS) circuitKnock Sensor (KS)ECM/PCt\411-130
P033s{4}Crankshaft PositionSensor CircuitCrankshaft Position SensorCrankshaft Positaon Sensor circuitE Cl\,l/PC l\,'!11-131
P0336(4)Crankshaft Position SensorRange/PerformanceCrankshaft Position SensorTiming belt skipped teeth11,131
P0420{67)Catalyst System Efficiency BelowThresholdThree Way Catalytic convenerSecondary HO2S {Sensor 2)'t1-200
P0441*3 (92)
Evaporative EmissionControlSystemInsulficient Purge Flow
EVAP Purge Control Solenoid valveEVAP Purge Control Solenoid valve circuitThrottle gody (purge port)TubingPCM
'It 205
P0451*5FuelTank Pressure Sensor CircuitBange/PerformanceFuel Tank Pressure SensorECM/PCMt't-208
(91iFuel Tank Pressure SensorCirclit Low InputOpsn orShort in FuelTank Pressure Sensor circuitFuel Tank Pressure SensorECM/PCt\411-209
P0453*r.5 {91)FuelTank Pressure Sensor CircuitHigh InputOpen in Fuel Tank Pressure Sensor circuitFuel Tank Pressure SensorECt /PCt\.111-211
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DTC(MlL indicationlDotection ltomProbable CausePage
P0500 t17)*,
Vehicle SpeedSensor CircuitMalfunction
Vehicle Speed SensorVehicle Speed Sensor circu itECtVI1 1-135
P0501 l17J*1
Vehicle SpeedSensor CircuitMalfunction
Vehicle Speed SensorVehicle Speed Sensor circuitPCM11-135
P0505 (14)ldle ControlSystemMalfunction
IAC valveThrottle BodyFast idle thermo valve*11 ']- 150
P0700P0715PO720P0730P0740P0753P0758
AutomaticTransaxle
Section l4
P1106 (13)BarometricPressure CircuitRange/Performance Problem
ECM/PCM (Baro sensor)
11-137
P1107 (13)BarometricPressure CircuitLow InPut
. ECM/PCM {Baro sensor)11-137
P1108 (13)BarometricPressure CircuitHigh Inpur
ECM/PCM {Baro sensor)11,137
P1121 (7)Throttle PositionLower ThanExpected
. TP sensor11-109
P1122 (7)Throttle PositionHigher ThanExpected
' TP sensor1 1-'109
P112a (5)Manifold AbsolutePressure Lower ThanExpected
. MAP sensor11-94
P1129 (5)Manifold AbsolutePressure HiqherThanExpected
' MAP sensor1l-94
P1297 (20)Electrical LoadDetector CircuitLow Input
Electrical Load DetectorElectrical Load Detector circuitECM/PCM1 1- 138
P1298 (20)Electrical LoadDetector CircuitHigh Input
Electrical Load DetectorElectrical Load Detector circuitECM/PCM11-140
P1300'3
P0301P0302P0303P0304
7l721314
Random lvlisfirelgnition systemFuel supply systemMAP sensorIAC valveContaminated fuelLack offuel
11-126
*: These DTCS will be indicated by the blinking of the Malfunction Indicator Lamp {MlL} with the SCS service connector
connected.**:The E (E])+s indicator light and the Malfunction Indicator Lamp (MlL) may come on simultaneously.*1:A,./T "3: '97 model +5: '99 - 00 models*2: M/T *4:'98 model
{cont'd)
11-77
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Troubleshooting
Diagnostic Trouble Code (DTCI Ghart (cont'd)
r: These DTCS will be indicated by the blinking oJ the Malfunction Indicator Lamp (MlL) with the SCS service connectorconnected.**: The Di (E)*5 indicator light and the Malfunction tndicator Lamp (MlL) may come on simultaneously.*1: A[f *3;'97 model *5: '99 - 00 models*21M/f *4: '98 model
11-78
DTC
{MlL indication}Detection ltemProbable CausePagc
P1336 154)Crankshaft SpeedFluctuation SensorIntermittent Interruption
. CKF sensor
11-142
P1337 i54)Crankshaft SpeedFluctuation SensorNo Signal
CKF sensorCKF sensor circuitECM,FCM11-142
P1359 (8)Crankshaft Position/Too DeadCenter Sensorrcylinder PositionConnector Disconnection
' CKP/TDC/CYP sensor circuit11-146
P1361 (8)Top Dead CenterSensor IntermittentInterruption11-131
P1362 (8)Top Dead CenterSensor No SignalTDC sensorTDC sensor circuitECM/PCM11-131
P1381 (9)Cylinder Position SensorIntermittent Interruption
. CYP sensor11-131
P1382 (9)Cylinder Position SensorNo SignalCYP sensorCYP sensor circuitECM/PCM11-131
P1456n.* {90}
Evaporative EmissionControl System Leak Detected(FuelTank System)
Fuelfill capVacuum connectionFueltankFuel tank prossure sensorEVAP bypass solenoid valveEVAP two way valveEVAP control canister vent shut valveEVAP control canisterEVAP purge controlsolenoid valve
11-213
Pr457n.s {90)
Evaporative EmissionControl System Leak Detected(EVAP Control Canister Svstem)
Vacuum connectionEVAP control canisterFuel tank pressure sensorEVAP bypass solenoid valveEVAP two way valveEVAP control canister vent shut valveFueltankEVAP purge controlsolenoid valve
11-219
P1508 (14)ldle Air ControlValve CircuitFailure
IAC valveIAC valve circuitECM/PCM11-152
Pr607(-)Engine Control Module,PowertrainControl Module Internal CircuitFailure A
. ECM,FCM11-147
P1705P1706P1753P1758P1768
AutomaticTransaxle
Section '14
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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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NOTE:. When there is no Diagnostic Trouble Code (DTC) stored, the MIL will stay on if the SCSservice connector is connected and the ignition switch is on.. lf this svmotom is intermittent, check for:- A loose Fl E/M (15 Aifuse in the underdash tuse/relay box- A loose No. 13 FUEL PUMP {15 A) fuse in the under-dash fuse/relay box- An intermittent short in the wire between the PCM (C7) and the service check con-
- An intermittent short in the wire between the PCM (A18) and the gauge assembly- An intermittent shon in the wire betlveen the PCM (D4) and the MAP sensor- An intermiftent short in the wire between the PCM {D10) and the TP sensor.PGM-Fl main relay.'See the OBD ll scan tool or Honda PGM Tester user's manuals lor specilic operatinginstructions,
NOTE: An open or short in the wire between the PCM (C8) and the DLC will keep thescan tool or Honda PGM Tester lrom communicating with the PCM. You should ioterpretthis as no DTCS are indicated.
PCM CONNECTORc l3lPl scs .BRNI
lTo page 11 84)Wire sid6 of f€male terminalg
(cont'dl
11-83
The Malfunciion lndicator Lamo{MlL) stavs on o. comes on afteltwo seconds,
Check the Oiegnosiic TroubleCode (DTC):
1. Connect an OBD ll scan toolor Honda PGM Tester.2. Turn the ignition switch ON 1lli.3. Read the DTC with the scantool or Honda PGII Tester.
Go to troubleshooting procedures(s€€ page 11501.Are any DTCIs) indicated?
Ch6ck lh6 DTC by MIL indication:1. Turn the ignition switch OFF.2. Connect the SCS service con-nector to the service checkconnector.3. Turn the ignition switch ON (ll).
- Repair opon or short in wi.6between the PCM (C8) andData Link Connector.- Go to troubloshooting proce-
dur€s {3ee page 11-601.
Does the MIL indicate any DTc?
Try to start the engine.
Does the engine start?
Check tor a short in the wire{SCS line):1. Turn the ignition switch OFFand turn the ignition switchoN flt).2. Measure voltage between thePCM connector terminal C7and body ground.
Repair short to body ground inthe wire between PCM lCTl andservice check connector.ls there approx. 5 V?
(To page 1'l-84)
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