System DescriPtion
Electrical Connections
FUELIN'ECTOHS
EVAP COIiTIBOL CANISTEAvE|rISHUT VAIVE
sotENoto vaLvE
lo FAOIAIOB FAN FELAY,CONOEI{SEh FAN FELAY
FUSESr-1) BATTERY {100 A)*
€) INTERIOF LIGHT {7.5 A}.
€) HORN STOP 120 A)'
o rcl (,$ A)*
o BACK UP IRADIO) 17.5 A)*
@ Fr €/M t15 Al'.'I NO. .I3 FUEL PUMP ISRS UNIN (15 A)
a,J No. 25 METER 17.5 Al
O No. 15 ALTERNATOR SP SENSOR {7.5 A}(0 No. 17 HEATER A/C R€LAY (7.5 A)(i) No. 31 STAnTEB SIGNAL (7.5 A)
*: in the under'hood fuse/relaY box
Engine Control Module Terminal Arrangement
ECM CONNECTOR A I32P}
ECM CONNECTOR A I32PI
*1: USA*2:818C1 engine*3:A,/T*4: 818C1, 818C5 engines
female terminals
NOTEr Standard battery voltageis 12 V.
{cont'di
LG22A
TerminalWireTerminal nameDescriptionSignal
YELlNJ4 (No. 4 FUEL INJECTOR)Drives No. 4 fuel iniector.With engine running: pulses2BLUlNJ3 (No.3 FUEL INJECTOR)Drives No. 3 fuel injector.
3REDlNJ2 (No.2 FUEL INJECTOB)Drives No.2 fuel injector.
BRNlNJl (No. 1 FUEL INJECTOR)Drives No. l Iuel iniector.
5GRN/REDS 02SHTC (SECONDARY
HEATED OXYGEN SENSORHEATER CONTROL)
Drives secondary heated oxygensensor heater,With ignition switch ON (ll)i battery volrageWith fully warmed up engine runningiduty controlled
6ORN/BLKP O2SHTC {PRIMARY HEAIEDOXYGEN SENSOB HEAIERCONTFOL)
Draves primary heated oxygensensor heater,With ignition swirch ON (ll): battery voltageWith lully warmed up engine running:duty controlled
84G RNI/ELVTS (VTEC
SOLENOID VALVE)Drives VTEC solenoid valve.With engine at low rpm: 0 VWith engine at high rpm: battery voltageIBRN/BLKLG1 (LOGIC GROUND)Ground for the ECM control circuit.Less than 1.0 V at alltimes10BLKPGl (POWER GROUND)Ground for the EC[, power circuit.Less than 1.0 V at all times't'lYEUBLKIGPl {POWER SOURCE)Power source for the ECMcontrolcircuit.With ignition switch ON 1ll): battery voltageWith ignition switch OFF| 0 V
12BLI(8LUIACV(IDLE AIR CONTROL VALVE}Drives IACV.With engine running: about 6 V 10 V(depending on engine speed)
REDPCS (EVAP PURGE CONTROLSOLENOID VALVE)Drives EVAP purge controlsolenoid valve.Wilh engane running, engine coolant above154"F (68'C): duty controlled
GRN/BLUFLR (FUEL PUMP RELAY)Drives fuel pump relay.0 V for two seconds after turning ignitionswitch ON (ll), then battery voltage
17B LVBEDACC (fuC CLUTCH RELAY)Drives A,/C clulch relay.With compressor ON: 0 VWith compressor OFFt baftery voltage
18GRN/ORNMIL (I\4ALFUNCTION
INDICATOR LAMPiDrives MlL.With MIL turned ON:0 VWjth MIL turned OFF: battery vottage
19*,WHT/GRNALTC (ALTERNATOR
CONTROL)Sends alternator control signal,With fully warmed up engine runninglbattery voltageDuring driving with small electrical load: 0 V
20YEUGRNICM (IGNITION CONTROLMODULE)Sends ignition pulse.With ignition switch ON (ll): battery voltageWith engine running: about'10 V(depending on engine speed)22BRN/BLKLG2 (LOGIC GROUND)Ground forthe ECM controlcifcuit.Less than 1.0 V at all times8LKPG2 (POWEfl GROUND)Ground for the ECM power circuit.Less than 1.0 V at all times
24YEUELKIGP2 (POWER SOURCE)Power source for the ECMcontrolcircuit,With ignition switch ON {lli: battery voltageWith ignition switch OFF: 0 V
25*3WHT/BLKVREF (REFERENCE VOLTAGE)Provides reference voltage toother control units,With ignition swirch ON (ll): about 5 VWath ignition switch OFF: 0 V
26. 'PNK/8LU
IAB SOL (INTAKE AIR BYPASSCONTROL SOLENOID VALVE)Drives IAB conlrol solenoidWith engrne running, engrae speed betow5,750 rpm: battery voltageWith engine running, engine speed above5,750 rpm: 0 V
27* IGRNFANC (BADIATOR FANCONTROL)Drives radiator fan relay.With radiator {an running: 0 VWith radiator Ian stopped: battery voltage
2ABLU2WBS (EVAP BYPASSSOLENOID VALVE)Drives EVAP bypass solenoidWith ignition switch ON (ll): battery vottage
29LT GRNVSV (EVAP CONlROLCANISTER VENT SHUT VAVLE)Drives EVAP control canister ventshut valve.Wilh ignilion switch ON lll): banery votrasc
1 1-39
DTC(MlL indicationlDeteciion ltemProbable CausoPage
P013s {41)
Primary Heated Oxygen Sensor
Heater
Circuit Malfunction {Sensor '1)
. Open or shon in Primary HO2S (Sensor 1) heater
circuit. ECM1't-74
P0137 (63)Secondary Heated Oxygen
Sensor
Circuit Low Voltage (Sensor 2)
Short in Secondary HO2S (Sensor 2) circuit
Secondary H02S {Sensor 2)
ECM11-7'l
P0138 {63)
Secondary Heated Oxygen
Sensor
Circuit High Voltage (Sensor 2)
Open in Secondary HO2S (Sensor 2) circuit
Secondary HO2S (Sensor 2)
ECM
P0139 (63)Secondary Heated Oxygen
Sensor
Slow Response (Sensor 2)
Secondary HO2S (Sensor 2)
P0141 (651Secondary Heated Oxygen
Sensor Heater
Circuit Malfunction (Sensor 2)
. Open or short in Secondary HO2S(Sensor 2) heater circuit. ECM11-'14
P0171 (45)
System Too LeanFuel supply system
Primary HO2S {Sensor I )MAP sensor
Contaminated fuel
Valve clearance
Exhaust leakage
11-76
P0172 t45l
System Too RichFuel supply system
Primary HO2S (Sensor 1)
MAP sensor
Contaminated fuel
Valve clearance
11.76
,...,{iil
174l
Random Misfirelgnition system
Fuel supply system
MAP sensor
IAC valve
Contaminated fuel
Lack offuel
't 1-78
P0301 (71)
P03Q2 l'121
P0303 (73)
P0304 (74)
- Cylinder 1- Cylinder 2- Cylinder 3- Cylinder 4
Misfire Detected
Fuel injector
Fuel injector circuit
lgnition system
Low compression
Valve clearance
11-79
P0325 {23)
Knock Sensor Circuit
MalfunctionOpen or short in Knock Sensor circuit
Knock Sensor
ECM11-82
P0335 (4)Crankshaft Position
Sensor Circuit
Malfunction
Crankshaft Position Sensor
Crankshaft Position Sensor circuit
ECM1 1-83
P0336 (4)Crankshaft Position
Sensor
Range/Performance
. Crankshaft Position Sensor. Timing belt skipped teethIl-83
P0420 (67)Catalyst System Efficiency
Below Threshold
. Three Way Catalytic converter. Secondary HO2S11-139
(cont'd)
11-43
PGM-FI System
System Description
ENGINE CONTROL MODULE (ECM)OUTPUTS
*1: USA*2: 818C1 engine*3: A,/T*4: 818C1, 818C5 engines
PGM-FI Sy3tem
The PGM-Fl system on this model is a sequential multiport fuel injection system.
Fuel lniector Timing and Duration
The ECM contains memories for the basic discharge durations at various engine speeds and manifold pressures. 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 Ai. Control Valve (lAC Valve)
When the engine is cold, the Ay'C compressor is on. the transmission is in gear (Ay'T only)the brake pedal is depressed, the
P/S load is high, or the alternator is charging, the ECM controls current to the IAC Valve to maintain correct idle speed.
lgnition Timing Control
. The ECM contains memories for basic ignition timing atvarious engine speeds and manifold pressures, lgnitiontiming
is also adjusted for engine coolant temperature.
. AKnockControl System isadoptedwhich sets the ideal ignition timing for the octane n um ber of gasoline used*r,
Other Control Functions
L Starting Control
When the engine is started, the ECM provides a rich mi{ure by increasing fuel injector duration.
2. Fuel PumD Control
. When the ignition switch is initially turned on, the ECM supplies 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 supplies ground to the PGM-FI main relay that supplies current to the fuel
DUmO.
. When the engine is not running and the ignition is on. the ECM cuts ground to the PGM-FI main relay which cuts
current to the fuel oumo.
INPUTS
TDc/CKP/CYP Sensor
CKF Sensor
MAP Sensor
ECT Sensor
IAT Sensor
TP Sensor
HO2S
VSS
BARO Sensor
ELD*1
Starter Signal
ALT FR Signal
Air Conditioning Signal
A,/T Gear Position Signal*3
Battery Voltage (lGN.1)
Brake Switch Signal
PSP Switch Signal*'
Knock Sensor*1
VTEC Pressure Switch*4
Fuel Tank Prssure Sensor
Fuel InjectorTiming and Duration
Electronic ldle Control
Other Control Functions
lgnition Timing Control
ECM Back-uD Functions
Fuel-lnjectors
PGM-Fl Main Relay (Fuel Pump)
MIL
IAC Valve
A,/C Compressor Clutch Relay
Radiator Fan Belay*1
Condenser Fan Relay
ALT*1
rcM
EVAP Purge Control Solenoid
Valve
H02S Heater
VTEC Solenoid Valve*'
IAB Control Solenoid Valve*,
EVAP Bypass Solenoid Valve
EVAP Control Canister Vent
Shut Valve
11-48
Primary Heated Oxygen Sensor (HO2S) lsensor 1l
The Heated Oxygen Sensor {HO2S) detects the oxygen content in the exhaust gas and signals the ECM. In operation, theECM receives the signals from the sensor and varies the duration during which fuel is iniected. To stabilize the sensor,soutput, the sensor has an internal heater and the sensor element is coated with a catalyst. The HO2S is installed in TWChousing (818C'1, 818C5 engines) or exhaust pipe B {81881 engine).
ztFcoNtAEI."EMEI'IT
SENSORTERMINALVOLTAGE IV)
HEATERIIEATERTERMINAL
RICH. AIR. * LEANFUELRANO
Thescantool indicates Diagnostic Trouble Code IDTCI PO13l: A low voltage problem in the primary
Heated Oxygen Sensor (HO2S) (Sensor 1) circuit.
- Th6 MIL h.r baan.ago.t.d on.- DTC m131 it 3to..d.
Problcm vcrificrtion:1. Do the ECM Reset Procedure.2. Start the engino. Hold theengane at 3,000 rpm with noload lin Park or neutral) untilth€ radiator Ian cofies on.3. Test-drive with the A,/T in Eposition, M/T in 4th gear.4. Check the Primary flO2S {S€n-sor 1) output voltage with thescan tool during accelerationusing wide open throttle.
Intarmittcnt f.ilur., 3yatam b OK.t thia tima. Ch.ck for poor con.nrctiona or loosa wiraa at C113(Prim.ry HO2S ls.n.or lll rndECM.
Chock the fuel pres6ure (see psge11-'t 18).
{To page 11-68)
(cont'd)
11-67
PGM-FI System
Primary,Heated Oxygen Sensor (HO2S) (Sensor 1) (cont'dl
The scan tool indicates Diagnostic Trouble Code (DTC) P0133: A slow response problem in the Primary
Heated Oxygen Sensor (HO25) (Sensor 1) circuit.
Description
By controlling the airlfuel ratio with a Primary HO2S (Sensor 'l) and a Secondary HO2S (Sensor 2), the deterioration of the
primary HO2S {Sensor 1) can be evaluated by its teedback period. When the feedback period of the HO2S exceeds a cer-
lain value during stable driving conditions, the sensor will be judged as deteriorated.
When deterioration has been detected during two consecutive trips, the MIL comes on and DTC P0133 will be stored
NOTE: ll DTC P013't, P0132 and/or P0'135 are stored at the same time as DTC P0133, troubleshoot those DTCS first, then
troubleshoot DTC P0133.
Possible Cause
. Primary HO2S (sensor 1) Deterioration
o Primary HO2S Heater (sensor 1) Deterioration
. Exhaust system leakage
Troubl€shooting Flowchart
')
litll r
- Tho MIL has boon raDortcd on.- DTC P0133 is storcd.
Problem verificttion:1. Do the ECM Reset Procedure.2. Start the engine. Hold thoengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on.3. Connect the SCS service con-
4. Test'drive Lrnder f o llowingconditions.* 55 mph (89 km/h) steadyspeed- NT in E position, M/T in5th gear- Until readiness code com€son
lnt.flnittcnt ftilu... ay3tam ia OKat thb tiinr. Ch.ck fo. poor con-necliona o. looaa wita! al Cll3
lPrim.ry HO2S lscn.or lll lndECM.
ls DTC P0133 indicated?
Roplacs the Primary HO2S lscn-3or 1),
PGM-FI System
Heated Oxygen Sensor (HO2S) Heater
The scan tool indicates Diagnostic Trouble code (DTC) P0135: A problem in the Primary Heated oxygen
Sensor lHO2S) (Sensor 'l) Heater circuit
The scan tool indicates Diagnostic Trouble Code (DTC)P0141: A problem in the Secondary Heated Oxygen
Sensor {HO25) {Sensor 2) Heater circuit
Fo13sl
lFol4il
PRIMARY Ho2S (sen3or 1) CONNECToR C113,
SECONDARY HO2S (sensor 2l CONNECTOR Cil51'
Terminal side of male terminals
PRIMARY HO2S (SonSor 1l CONNECTOR Cl13,
SECONDARY HO2S lsan3or 2) CONNECTOR C451r
o2sHTC(BLK/WHT,
GRN/REO'}
IGP{YEL/BLK}lGlr(BLK/YEL)
(To page 11-75)*: P0141
- The MIL has been rePorted on- DTC P0135 and/or P0141 ate
stored.
Probl€m verilication:1. Do the ECM Reset Procedure
2. Start the engine.
lnt€rmitlent failure. 3vslem is OK
at this time. Check for Poo. con'
noction3 o. loose wire ai Cl13(Primary HO2S (S.nsor 1ll. gl51
lSocondary H02S lSensor 2))'
and ECM.
Check for an open or short in tho
HO2S:1. Turn the ignition switch OFF.2. Disconnect the Primary HO2S(Sensor 1) Secondary HO2S
{Sensor 2)'connector,3. At the HO2S side measureresistance between the 4P con-nector No. 3 and No. 4 terminals on the HO2S side.
ls there 10 - 40 0?
Check Ior continuity betweenbody ground and the HO2S 4P
connector lerminals No. 3 andNo.4 individually.
ls there continuity?
Ch€ck for an open or short in thewir63 (lGP, lG1*, O2SHTC lines):1. Turn the ignition switch ON (ll).
2. Measure voltage between No.3 terminal and No. 4 terminalon the harness side of the 4P
ls there batlery vohage?
{1o page 1l-75)Wire side of female terminals
PGM-Fl System
Fuel Supply System
lF0{7il Thescantool indicates Diagnostic Trouble Code (DTC) P0171:Theluel system rstoo lean
[F0i72l Th" ""un tool indicates Diagnosric Trouble code (DTc) p0,172: The fuet system is too rich
Description
By monitoring the Long Term Fuel Trim, long term malfunctions in the luel system will be detected
lf a malfunction has been detected during two consecutive trips, the MIL will come on and DTC P0171 and/or P0172 will be
stored.
NOTE: lf some ol the DTCS lasted below are stored at the same time as DTC PolTl and/or P0172 troubleshoot those DTCS
first, then troubleshoot DTC P0171 andlot P0172
PO107, P0108, P1128. P1129: MAP Sensor
P0135: Primary HO2S Heater (Sensor 1)
P0137, P0138: Secondarv HO2S (Sensor 2)
P0141: Secondary HO2S Heater (Sensor 2)
P1259: VTEC Svstem
Possible Cause
DTC P0171
too lean
Drc P0172
Svstem too rich
. Fuel Pump insufficient flowpressure
. Fuel Feed Line clogged, leaking
. Fuel Pressure Regulator stuck open
. Fuel Filter clogged. Fuel Iniector clogged, air inclusion
. Gasoline doesn't meet Owner's Manual spec.
. Primary HO2S (Sensor 1)deteriorated
. Valve Clearance. Exhaust leak
. Fuel Pressure Regulator clogged, stuck closed
. Fuel Return Pipe clogged
. Fuel Iniector leaking
. Gasoline doesn't meet Owner's Manual spec
' Primary Ho2s (Sensor 1) deteriorated
. Valve Clearance